Kelsidavis-WoWee/tools/editor/cli_gen_mesh.cpp

#include "cli_gen_mesh.hpp"

#include "pipeline/wowee_model.hpp"
#include <glm/glm.hpp>
#include <glm/gtc/matrix_transform.hpp>

#include <algorithm>
#include <cmath>
#include <cstdint>
#include <cstdio>
#include <cstring>
#include <filesystem>
#include <map>
#include <string>
#include <utility>
#include <vector>

namespace wowee {
namespace editor {
namespace cli {

namespace {

int handleRock(int& i, int argc, char** argv) {
    // Procedural boulder. Starts as an octahedron, subdivides
    // each face N times to get a rounded base, then displaces
    // each vertex along its outward direction by a smooth
    // sin/cos noise term controlled by `seed` and `roughness`.
    // Result is a unique-shaped rock per seed — perfect for
    // scattering across a zone via random-populate-zone.
    //
    // The 16th procedural primitive in the WOM library.
    std::string womBase = argv[++i];
    float radius = 1.0f;
    float roughness = 0.25f;  // 0..1, fraction of radius
    int subdiv = 2;           // 0=8 tris, 1=32, 2=128, 3=512
    uint32_t seed = 1;
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { radius = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { roughness = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { subdiv = std::stoi(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { seed = static_cast<uint32_t>(std::stoul(argv[++i])); } catch (...) {}
    }
    if (radius <= 0 || roughness < 0 || roughness > 1 ||
        subdiv < 0 || subdiv > 4) {
        std::fprintf(stderr,
            "gen-mesh-rock: radius>0, roughness 0..1, subdiv 0..4\n");
        return 1;
    }
    if (womBase.size() >= 4 &&
        womBase.substr(womBase.size() - 4) == ".wom") {
        womBase = womBase.substr(0, womBase.size() - 4);
    }
    // Build sphere via octahedron subdivision. Vertices are
    // accumulated in unit-length form first, then displaced.
    std::vector<glm::vec3> sv;  // sphere verts (unit)
    std::vector<glm::uvec3> st; // sphere tris (vertex indices)
    sv = {
        { 1, 0, 0}, {-1, 0, 0},
        { 0, 1, 0}, { 0,-1, 0},
        { 0, 0, 1}, { 0, 0,-1},
    };
    st = {
        {0, 2, 4}, {2, 1, 4}, {1, 3, 4}, {3, 0, 4},
        {2, 0, 5}, {1, 2, 5}, {3, 1, 5}, {0, 3, 5},
    };
    // Edge-midpoint cache so shared edges don't duplicate verts.
    for (int s = 0; s < subdiv; ++s) {
        std::map<std::pair<uint32_t,uint32_t>, uint32_t> midCache;
        auto midpoint = [&](uint32_t a, uint32_t b) -> uint32_t {
            auto key = std::make_pair(std::min(a,b), std::max(a,b));
            auto it = midCache.find(key);
            if (it != midCache.end()) return it->second;
            glm::vec3 m = glm::normalize((sv[a] + sv[b]) * 0.5f);
            uint32_t idx = static_cast<uint32_t>(sv.size());
            sv.push_back(m);
            midCache[key] = idx;
            return idx;
        };
        std::vector<glm::uvec3> next;
        next.reserve(st.size() * 4);
        for (auto& tri : st) {
            uint32_t a = tri.x, b = tri.y, c = tri.z;
            uint32_t ab = midpoint(a, b);
            uint32_t bc = midpoint(b, c);
            uint32_t ca = midpoint(c, a);
            next.push_back({a,  ab, ca});
            next.push_back({b,  bc, ab});
            next.push_back({c,  ca, bc});
            next.push_back({ab, bc, ca});
        }
        st.swap(next);
    }
    // Smooth pseudo-noise displacement. Three orthogonal sin
    // products give a coherent bumpy surface; phase shift uses
    // the seed so each value yields a distinct silhouette.
    float sf = static_cast<float>(seed);
    auto displace = [&](glm::vec3 p) -> float {
        float n = std::sin(p.x * 3.1f + sf * 0.91f) *
                  std::sin(p.y * 4.7f + sf * 1.37f) *
                  std::sin(p.z * 5.3f + sf * 0.43f);
        float n2 = std::sin(p.x * 7.1f + sf * 0.11f) *
                   std::sin(p.y * 8.3f + sf * 2.13f) *
                   std::sin(p.z * 9.7f + sf * 1.91f);
        return 1.0f + roughness * (0.7f * n + 0.3f * n2);
    };
    wowee::pipeline::WoweeModel wom;
    wom.name = std::filesystem::path(womBase).stem().string();
    wom.version = 3;
    std::vector<glm::vec3> finalPos(sv.size());
    for (size_t v = 0; v < sv.size(); ++v) {
        finalPos[v] = sv[v] * (radius * displace(sv[v]));
    }
    // Per-vertex normals from triangle face normals (averaged).
    std::vector<glm::vec3> normals(sv.size(), glm::vec3(0));
    for (auto& tri : st) {
        glm::vec3 a = finalPos[tri.x];
        glm::vec3 b = finalPos[tri.y];
        glm::vec3 c = finalPos[tri.z];
        glm::vec3 fn = glm::normalize(glm::cross(b - a, c - a));
        normals[tri.x] += fn;
        normals[tri.y] += fn;
        normals[tri.z] += fn;
    }
    for (auto& n : normals) n = glm::length(n) > 1e-6f
        ? glm::normalize(n) : glm::vec3(0, 1, 0);
    for (size_t v = 0; v < sv.size(); ++v) {
        wowee::pipeline::WoweeModel::Vertex vtx;
        vtx.position = finalPos[v];
        vtx.normal = normals[v];
        // Spherical UV unwrap. Visible seam at u=0/1 is
        // acceptable for rocks — usually hidden by terrain.
        glm::vec3 d = glm::normalize(sv[v]);
        vtx.texCoord = {
            0.5f + std::atan2(d.z, d.x) / (2.0f * 3.14159265f),
            0.5f - std::asin(d.y) / 3.14159265f,
        };
        wom.vertices.push_back(vtx);
    }
    for (auto& tri : st) {
        wom.indices.push_back(tri.x);
        wom.indices.push_back(tri.y);
        wom.indices.push_back(tri.z);
    }
    float bound = radius * (1.0f + roughness);
    wom.boundMin = glm::vec3(-bound);
    wom.boundMax = glm::vec3( bound);
    wowee::pipeline::WoweeModel::Batch batch;
    batch.indexStart = 0;
    batch.indexCount = static_cast<uint32_t>(wom.indices.size());
    batch.textureIndex = 0;
    wom.batches.push_back(batch);
    if (!wowee::pipeline::WoweeModelLoader::save(wom, womBase)) {
        std::fprintf(stderr,
            "gen-mesh-rock: failed to save %s.wom\n", womBase.c_str());
        return 1;
    }
    std::printf("Wrote %s.wom\n", womBase.c_str());
    std::printf("  radius    : %.3f\n", radius);
    std::printf("  roughness : %.3f\n", roughness);
    std::printf("  subdiv    : %d\n", subdiv);
    std::printf("  seed      : %u\n", seed);
    std::printf("  vertices  : %zu\n", wom.vertices.size());
    std::printf("  triangles : %zu\n", wom.indices.size() / 3);
    return 0;
}

int handlePillar(int& i, int argc, char** argv) {
    // Procedural classical column. Central shaft is a
    // cylinder with N concave flutes (radius modulated by
    // cos²(theta*flutes/2)), capped above and below by
    // wider disc caps that act as a simple capital and
    // base. The 17th procedural mesh primitive — useful
    // for ruins, temples, dungeons, plaza decoration.
    std::string womBase = argv[++i];
    float radius = 0.4f;
    float height = 4.0f;
    int flutes = 12;
    float capScale = 1.25f;
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { radius = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { height = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { flutes = std::stoi(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { capScale = std::stof(argv[++i]); } catch (...) {}
    }
    if (radius <= 0 || height <= 0 ||
        flutes < 4 || flutes > 64 ||
        capScale < 1.0f || capScale > 4.0f) {
        std::fprintf(stderr,
            "gen-mesh-pillar: radius>0, height>0, flutes 4..64, capScale 1..4\n");
        return 1;
    }
    if (womBase.size() >= 4 &&
        womBase.substr(womBase.size() - 4) == ".wom") {
        womBase = womBase.substr(0, womBase.size() - 4);
    }
    const float pi = 3.14159265358979f;
    // We use 8 segments per flute so the cosine-modulated
    // groove resolves smoothly. Vertical: 2 rings (top/bot
    // of shaft) + cap/base discs.
    const int radSegs = flutes * 8;
    const float fluteDepth = radius * 0.12f;
    float capR = radius * capScale;
    float capThick = radius * 0.25f;
    wowee::pipeline::WoweeModel wom;
    wom.name = std::filesystem::path(womBase).stem().string();
    wom.version = 3;
    auto addV = [&](glm::vec3 p, glm::vec3 n, glm::vec2 uv) -> uint32_t {
        wowee::pipeline::WoweeModel::Vertex vtx;
        vtx.position = p; vtx.normal = n; vtx.texCoord = uv;
        wom.vertices.push_back(vtx);
        return static_cast<uint32_t>(wom.vertices.size() - 1);
    };
    // Shaft side ring at given y. radius modulated by flute count.
    auto buildShaftRing = [&](float y) -> uint32_t {
        uint32_t start = static_cast<uint32_t>(wom.vertices.size());
        for (int sg = 0; sg <= radSegs; ++sg) {
            float u = static_cast<float>(sg) / radSegs;
            float ang = u * 2.0f * pi;
            float c = std::cos(ang * flutes * 0.5f);
            float r = radius - fluteDepth * (c * c);
            glm::vec3 p(r * std::cos(ang), y, r * std::sin(ang));
            glm::vec3 n(std::cos(ang), 0, std::sin(ang));
            addV(p, glm::normalize(n), glm::vec2(u, y / height));
        }
        return start;
    };
    // Cap/base disc ring (constant radius capR) at given y.
    auto buildCapRing = [&](float y, float r) -> uint32_t {
        uint32_t start = static_cast<uint32_t>(wom.vertices.size());
        for (int sg = 0; sg <= radSegs; ++sg) {
            float u = static_cast<float>(sg) / radSegs;
            float ang = u * 2.0f * pi;
            glm::vec3 p(r * std::cos(ang), y, r * std::sin(ang));
            glm::vec3 n(std::cos(ang), 0, std::sin(ang));
            addV(p, glm::normalize(n), glm::vec2(u, y / height));
        }
        return start;
    };
    // Layout (Y goes up):
    //   capThick: base disc bottom
    //   capThick: base disc top
    //   ...shaft from capThick to height-capThick...
    //   height-capThick: cap disc bottom
    //   height: cap disc top
    float shaftY0 = capThick;
    float shaftY1 = height - capThick;
    uint32_t baseBot = buildCapRing(0.0f, capR);
    uint32_t baseTop = buildCapRing(shaftY0, capR);
    uint32_t shaftBot = buildShaftRing(shaftY0);
    uint32_t shaftTop = buildShaftRing(shaftY1);
    uint32_t capBot = buildCapRing(shaftY1, capR);
    uint32_t capTop = buildCapRing(height, capR);
    // Quad connector helper.
    auto connect = [&](uint32_t a0, uint32_t a1) {
        for (int sg = 0; sg < radSegs; ++sg) {
            uint32_t i00 = a0 + sg;
            uint32_t i01 = a0 + sg + 1;
            uint32_t i10 = a1 + sg;
            uint32_t i11 = a1 + sg + 1;
            wom.indices.insert(wom.indices.end(),
                               { i00, i10, i01, i01, i10, i11 });
        }
    };
    connect(baseBot, baseTop);   // base side
    connect(shaftBot, shaftTop); // shaft
    connect(capBot, capTop);     // cap side
    // Bottom cap (downward fan), top cap (upward fan).
    uint32_t bottomCenter = addV({0, 0, 0}, {0, -1, 0}, {0.5f, 0.5f});
    uint32_t topCenter = addV({0, height, 0}, {0, 1, 0}, {0.5f, 0.5f});
    for (int sg = 0; sg < radSegs; ++sg) {
        wom.indices.insert(wom.indices.end(),
            { bottomCenter, baseBot + sg + 1, baseBot + sg });
        wom.indices.insert(wom.indices.end(),
            { topCenter, capTop + sg, capTop + sg + 1 });
    }
    // Annular surfaces where caps meet shaft (top of base disc
    // out to shaft, etc.). Just connect the two rings — they
    // sit at the same Y so this looks like a flat ring.
    connect(baseTop, shaftBot);
    connect(shaftTop, capBot);
    wowee::pipeline::WoweeModel::Batch batch;
    batch.indexStart = 0;
    batch.indexCount = static_cast<uint32_t>(wom.indices.size());
    batch.textureIndex = 0;
    wom.batches.push_back(batch);
    wom.boundMin = glm::vec3(-capR, 0,      -capR);
    wom.boundMax = glm::vec3( capR, height,  capR);
    if (!wowee::pipeline::WoweeModelLoader::save(wom, womBase)) {
        std::fprintf(stderr,
            "gen-mesh-pillar: failed to save %s.wom\n", womBase.c_str());
        return 1;
    }
    std::printf("Wrote %s.wom\n", womBase.c_str());
    std::printf("  radius    : %.3f\n", radius);
    std::printf("  height    : %.3f\n", height);
    std::printf("  flutes    : %d\n", flutes);
    std::printf("  cap scale : %.2fx (capR=%.3f)\n", capScale, capR);
    std::printf("  vertices  : %zu\n", wom.vertices.size());
    std::printf("  triangles : %zu\n", wom.indices.size() / 3);
    return 0;
}

int handleBridge(int& i, int argc, char** argv) {
    // Procedural plank bridge. Deck is N axis-aligned planks
    // running across the bridge's width with small gaps
    // between, plus two side rails (top + bottom rails on
    // posts). Bridge length runs along +X, width is on Z.
    // The 18th procedural mesh primitive — useful for
    // river crossings, dungeon catwalks, scenic overlooks.
    std::string womBase = argv[++i];
    float length = 6.0f;     // along X
    float width = 2.0f;      // along Z
    int planks = 6;          // plank count across the length
    float railHeight = 1.0f; // rail height above deck (0 = no rails)
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { length = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { width = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { planks = std::stoi(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { railHeight = std::stof(argv[++i]); } catch (...) {}
    }
    if (length <= 0 || width <= 0 ||
        planks < 1 || planks > 64 ||
        railHeight < 0 || railHeight > 4.0f) {
        std::fprintf(stderr,
            "gen-mesh-bridge: length>0, width>0, planks 1..64, rail 0..4\n");
        return 1;
    }
    if (womBase.size() >= 4 &&
        womBase.substr(womBase.size() - 4) == ".wom") {
        womBase = womBase.substr(0, womBase.size() - 4);
    }
    wowee::pipeline::WoweeModel wom;
    wom.name = std::filesystem::path(womBase).stem().string();
    wom.version = 3;
    // Box helper — builds 24-vert / 12-tri box centered on
    // (cx, cy, cz) with half-extents (hx, hy, hz). Each face
    // gets unique vertices so flat-shading works. Indices are
    // pushed into wom.indices directly.
    auto addBox = [&](float cx, float cy, float cz,
                      float hx, float hy, float hz) {
        glm::vec3 c(cx, cy, cz);
        struct Face {
            glm::vec3 n;
            glm::vec3 du, dv;  // unit-length axes spanning the face
        };
        Face faces[6] = {
            {{0, 1, 0}, {1, 0, 0}, {0, 0, 1}},   // top    (+Y)
            {{0,-1, 0}, {1, 0, 0}, {0, 0,-1}},   // bottom (-Y)
            {{1, 0, 0}, {0, 0, 1}, {0, 1, 0}},   // right  (+X)
            {{-1,0, 0}, {0, 0,-1}, {0, 1, 0}},   // left   (-X)
            {{0, 0, 1}, {-1,0, 0}, {0, 1, 0}},   // front  (+Z)
            {{0, 0,-1}, {1, 0, 0}, {0, 1, 0}},   // back   (-Z)
        };
        glm::vec3 ext(hx, hy, hz);
        for (const Face& f : faces) {
            glm::vec3 center = c + glm::vec3(f.n.x*hx, f.n.y*hy, f.n.z*hz);
            glm::vec3 du = glm::vec3(f.du.x*ext.x, f.du.y*ext.y, f.du.z*ext.z);
            glm::vec3 dv = glm::vec3(f.dv.x*ext.x, f.dv.y*ext.y, f.dv.z*ext.z);
            uint32_t base = static_cast<uint32_t>(wom.vertices.size());
            auto push = [&](glm::vec3 p, float u, float v) {
                wowee::pipeline::WoweeModel::Vertex vtx;
                vtx.position = p;
                vtx.normal = f.n;
                vtx.texCoord = {u, v};
                wom.vertices.push_back(vtx);
            };
            push(center - du - dv, 0, 0);
            push(center + du - dv, 1, 0);
            push(center + du + dv, 1, 1);
            push(center - du + dv, 0, 1);
            wom.indices.insert(wom.indices.end(),
                { base, base + 1, base + 2, base, base + 2, base + 3 });
        }
    };
    // Deck: planks along X, gap = 5% of plank pitch.
    float plankThickness = 0.08f;
    float plankPitch = length / planks;
    float plankWidth = plankPitch * 0.95f;
    for (int p = 0; p < planks; ++p) {
        float cx = -length * 0.5f + plankPitch * (p + 0.5f);
        addBox(cx, plankThickness * 0.5f, 0,
               plankWidth * 0.5f, plankThickness * 0.5f, width * 0.5f);
    }
    // Rails: 2 sides × (top rail + 3 posts) when railHeight > 0
    if (railHeight > 0.0f) {
        float postR = 0.06f;
        float topRailR = 0.08f;
        int postCount = 3;
        float rzOffset = width * 0.5f - postR;
        for (int side = 0; side < 2; ++side) {
            float zSign = (side == 0) ? 1.0f : -1.0f;
            float z = zSign * rzOffset;
            // Top rail: long thin box spanning length
            addBox(0, plankThickness + railHeight, z,
                   length * 0.5f, topRailR, topRailR);
            // Posts evenly spaced
            for (int p = 0; p < postCount; ++p) {
                float t = (postCount > 1)
                    ? static_cast<float>(p) / (postCount - 1)
                    : 0.5f;
                float cx = -length * 0.5f + length * t;
                if (p == 0) cx += postR;
                if (p == postCount - 1) cx -= postR;
                addBox(cx, plankThickness + railHeight * 0.5f, z,
                       postR, railHeight * 0.5f, postR);
            }
        }
    }
    wowee::pipeline::WoweeModel::Batch batch;
    batch.indexStart = 0;
    batch.indexCount = static_cast<uint32_t>(wom.indices.size());
    batch.textureIndex = 0;
    wom.batches.push_back(batch);
    float maxY = plankThickness + railHeight;
    wom.boundMin = glm::vec3(-length * 0.5f, 0,        -width * 0.5f);
    wom.boundMax = glm::vec3( length * 0.5f, maxY,      width * 0.5f);
    if (!wowee::pipeline::WoweeModelLoader::save(wom, womBase)) {
        std::fprintf(stderr,
            "gen-mesh-bridge: failed to save %s.wom\n", womBase.c_str());
        return 1;
    }
    std::printf("Wrote %s.wom\n", womBase.c_str());
    std::printf("  length    : %.3f\n", length);
    std::printf("  width     : %.3f\n", width);
    std::printf("  planks    : %d\n", planks);
    std::printf("  rail H    : %.3f%s\n", railHeight,
                railHeight > 0 ? "" : " (no rails)");
    std::printf("  vertices  : %zu\n", wom.vertices.size());
    std::printf("  triangles : %zu\n", wom.indices.size() / 3);
    return 0;
}

int handleTower(int& i, int argc, char** argv) {
    // Procedural castle tower. Solid cylindrical shaft with
    // crenellated battlements ringing the top: alternating
    // raised "merlons" and gaps. Each merlon is a thin
    // angular wedge sitting on the top rim. Useful for
    // keeps, watchtowers, perimeter walls.
    //
    // The 19th procedural mesh primitive.
    std::string womBase = argv[++i];
    float radius = 1.5f;
    float height = 8.0f;
    int battlements = 8;     // merlons around the rim
    float battlementH = 0.5f;
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { radius = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { height = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { battlements = std::stoi(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { battlementH = std::stof(argv[++i]); } catch (...) {}
    }
    if (radius <= 0 || height <= 0 ||
        battlements < 4 || battlements > 64 ||
        battlementH < 0 || battlementH > 4.0f) {
        std::fprintf(stderr,
            "gen-mesh-tower: radius>0, height>0, battlements 4..64, bH 0..4\n");
        return 1;
    }
    if (womBase.size() >= 4 &&
        womBase.substr(womBase.size() - 4) == ".wom") {
        womBase = womBase.substr(0, womBase.size() - 4);
    }
    wowee::pipeline::WoweeModel wom;
    wom.name = std::filesystem::path(womBase).stem().string();
    wom.version = 3;
    const float pi = 3.14159265358979f;
    const int radSegs = std::max(24, battlements * 4);
    auto addV = [&](glm::vec3 p, glm::vec3 n, glm::vec2 uv) -> uint32_t {
        wowee::pipeline::WoweeModel::Vertex vtx;
        vtx.position = p; vtx.normal = n; vtx.texCoord = uv;
        wom.vertices.push_back(vtx);
        return static_cast<uint32_t>(wom.vertices.size() - 1);
    };
    // Cylinder shaft: side ring at y=0 and y=height.
    uint32_t botRing = static_cast<uint32_t>(wom.vertices.size());
    for (int sg = 0; sg <= radSegs; ++sg) {
        float u = static_cast<float>(sg) / radSegs;
        float ang = u * 2.0f * pi;
        glm::vec3 p(radius * std::cos(ang), 0, radius * std::sin(ang));
        glm::vec3 n(std::cos(ang), 0, std::sin(ang));
        addV(p, n, glm::vec2(u, 0));
    }
    uint32_t topRing = static_cast<uint32_t>(wom.vertices.size());
    for (int sg = 0; sg <= radSegs; ++sg) {
        float u = static_cast<float>(sg) / radSegs;
        float ang = u * 2.0f * pi;
        glm::vec3 p(radius * std::cos(ang), height, radius * std::sin(ang));
        glm::vec3 n(std::cos(ang), 0, std::sin(ang));
        addV(p, n, glm::vec2(u, 1));
    }
    for (int sg = 0; sg < radSegs; ++sg) {
        wom.indices.insert(wom.indices.end(), {
            botRing + sg, topRing + sg, botRing + sg + 1,
            botRing + sg + 1, topRing + sg, topRing + sg + 1
        });
    }
    // Top cap (fan toward upward-facing center).
    uint32_t topCenter = addV({0, height, 0}, {0, 1, 0}, {0.5f, 0.5f});
    for (int sg = 0; sg < radSegs; ++sg) {
        wom.indices.insert(wom.indices.end(),
            { topCenter, topRing + sg, topRing + sg + 1 });
    }
    // Bottom cap (fan toward downward-facing center).
    uint32_t botCenter = addV({0, 0, 0}, {0, -1, 0}, {0.5f, 0.5f});
    for (int sg = 0; sg < radSegs; ++sg) {
        wom.indices.insert(wom.indices.end(),
            { botCenter, botRing + sg + 1, botRing + sg });
    }
    // Battlements: thin curved blocks around the top rim,
    // half the slots filled (alternating merlon/gap).
    // Each merlon is approximated by an extruded arc segment
    // at the wall radius extending outward slightly.
    if (battlementH > 0.0f) {
        int merlonSpan = radSegs / battlements;
        int merlonHalf = std::max(1, merlonSpan / 2);
        float outerR = radius * 1.05f;
        float innerR = radius * 0.95f;
        for (int b = 0; b < battlements; ++b) {
            int startSeg = b * merlonSpan;
            // Build 8-vert box-like segment between angles
            // covering merlonHalf slots (so half the rim is
            // filled, forming the merlon/gap pattern).
            float ang0 = 2.0f * pi * static_cast<float>(startSeg) / radSegs;
            float ang1 = 2.0f * pi * static_cast<float>(startSeg + merlonHalf) / radSegs;
            glm::vec3 outer0(outerR * std::cos(ang0), 0, outerR * std::sin(ang0));
            glm::vec3 outer1(outerR * std::cos(ang1), 0, outerR * std::sin(ang1));
            glm::vec3 inner0(innerR * std::cos(ang0), 0, innerR * std::sin(ang0));
            glm::vec3 inner1(innerR * std::cos(ang1), 0, innerR * std::sin(ang1));
            glm::vec3 yLow(0, height, 0);
            glm::vec3 yHigh(0, height + battlementH, 0);
            glm::vec3 norm = glm::normalize(
                outer0 + outer1 - inner0 - inner1);
            auto V = [&](glm::vec3 p, glm::vec3 n) {
                return addV(p, n, {0, 0});
            };
            // 8 verts: 4 corners × 2 heights
            uint32_t bbl = V(outer0 + yLow,  norm);   // bot outer left
            uint32_t bbr = V(outer1 + yLow,  norm);
            uint32_t btl = V(outer0 + yHigh, norm);   // top outer left
            uint32_t btr = V(outer1 + yHigh, norm);
            uint32_t ibl = V(inner0 + yLow,  -norm);  // bot inner left
            uint32_t ibr = V(inner1 + yLow,  -norm);
            uint32_t itl = V(inner0 + yHigh, -norm);  // top inner left
            uint32_t itr = V(inner1 + yHigh, -norm);
            // outer face
            wom.indices.insert(wom.indices.end(), {bbl, btl, bbr, bbr, btl, btr});
            // inner face
            wom.indices.insert(wom.indices.end(), {ibr, itr, ibl, ibl, itr, itl});
            // top face
            wom.indices.insert(wom.indices.end(), {btl, itl, btr, btr, itl, itr});
            // left and right end caps
            wom.indices.insert(wom.indices.end(), {bbl, ibl, btl, btl, ibl, itl});
            wom.indices.insert(wom.indices.end(), {bbr, btr, ibr, ibr, btr, itr});
        }
    }
    wowee::pipeline::WoweeModel::Batch batch;
    batch.indexStart = 0;
    batch.indexCount = static_cast<uint32_t>(wom.indices.size());
    batch.textureIndex = 0;
    wom.batches.push_back(batch);
    float maxY = height + battlementH;
    float maxR = radius * 1.05f;
    wom.boundMin = glm::vec3(-maxR, 0,    -maxR);
    wom.boundMax = glm::vec3( maxR, maxY,  maxR);
    if (!wowee::pipeline::WoweeModelLoader::save(wom, womBase)) {
        std::fprintf(stderr,
            "gen-mesh-tower: failed to save %s.wom\n", womBase.c_str());
        return 1;
    }
    std::printf("Wrote %s.wom\n", womBase.c_str());
    std::printf("  radius      : %.3f\n", radius);
    std::printf("  height      : %.3f\n", height);
    std::printf("  battlements : %d (%.3fm tall)\n",
                battlements, battlementH);
    std::printf("  vertices    : %zu\n", wom.vertices.size());
    std::printf("  triangles   : %zu\n", wom.indices.size() / 3);
    return 0;
}

int handleHouse(int& i, int argc, char** argv) {
    // Simple procedural house: cube body + pyramid roof
    // meeting at a central apex above the body's roofline.
    // The pyramid sits flush on the body so the eaves
    // line up with the wall edges. No door cutout — that
    // can be added later via mesh boolean ops or texture.
    //
    // The 20th procedural mesh primitive.
    std::string womBase = argv[++i];
    float width = 4.0f;       // along X
    float depth = 4.0f;       // along Z
    float height = 3.0f;      // wall height (Y)
    float roofH = 2.0f;       // pyramid above walls
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { width = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { depth = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { height = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { roofH = std::stof(argv[++i]); } catch (...) {}
    }
    if (width <= 0 || depth <= 0 || height <= 0 ||
        roofH < 0 || roofH > 20.0f) {
        std::fprintf(stderr,
            "gen-mesh-house: width/depth/height>0, roof 0..20\n");
        return 1;
    }
    if (womBase.size() >= 4 &&
        womBase.substr(womBase.size() - 4) == ".wom") {
        womBase = womBase.substr(0, womBase.size() - 4);
    }
    wowee::pipeline::WoweeModel wom;
    wom.name = std::filesystem::path(womBase).stem().string();
    wom.version = 3;
    auto addV = [&](glm::vec3 p, glm::vec3 n, glm::vec2 uv) -> uint32_t {
        wowee::pipeline::WoweeModel::Vertex vtx;
        vtx.position = p; vtx.normal = n; vtx.texCoord = uv;
        wom.vertices.push_back(vtx);
        return static_cast<uint32_t>(wom.vertices.size() - 1);
    };
    float hx = width * 0.5f;
    float hz = depth * 0.5f;
    // 4 walls — each a quad with an outward-facing normal so
    // the house reads as solid even with backface culling on.
    struct Wall {
        glm::vec3 a, b, c, d;  // CCW from outside
        glm::vec3 n;
    };
    Wall walls[4] = {
        {{ hx, 0,  hz}, {-hx, 0,  hz}, {-hx, height,  hz}, { hx, height,  hz}, { 0, 0,  1}}, // +Z
        {{-hx, 0, -hz}, { hx, 0, -hz}, { hx, height, -hz}, {-hx, height, -hz}, { 0, 0, -1}}, // -Z
        {{ hx, 0, -hz}, { hx, 0,  hz}, { hx, height,  hz}, { hx, height, -hz}, { 1, 0,  0}}, // +X
        {{-hx, 0,  hz}, {-hx, 0, -hz}, {-hx, height, -hz}, {-hx, height,  hz}, {-1, 0,  0}}, // -X
    };
    for (const Wall& w : walls) {
        uint32_t a = addV(w.a, w.n, {0, 0});
        uint32_t b = addV(w.b, w.n, {1, 0});
        uint32_t c = addV(w.c, w.n, {1, 1});
        uint32_t d = addV(w.d, w.n, {0, 1});
        wom.indices.insert(wom.indices.end(), {a, b, c, a, c, d});
    }
    // Floor (single quad, normal-down so it shows from below;
    // texturable as a foundation slab).
    {
        uint32_t a = addV({-hx, 0, -hz}, {0, -1, 0}, {0, 0});
        uint32_t b = addV({ hx, 0, -hz}, {0, -1, 0}, {1, 0});
        uint32_t c = addV({ hx, 0,  hz}, {0, -1, 0}, {1, 1});
        uint32_t d = addV({-hx, 0,  hz}, {0, -1, 0}, {0, 1});
        wom.indices.insert(wom.indices.end(), {a, c, b, a, d, c});
    }
    // Roof: 4 triangles meeting at central apex.
    float apexY = height + roofH;
    glm::vec3 apex(0, apexY, 0);
    // Eave corners (Y = wall height) — each triangle shares
    // two adjacent corners + the apex. Per-face normal is
    // computed once so flat shading works.
    glm::vec3 eaves[4] = {
        {-hx, height,  hz},
        { hx, height,  hz},
        { hx, height, -hz},
        {-hx, height, -hz},
    };
    for (int s = 0; s < 4; ++s) {
        glm::vec3 e0 = eaves[s];
        glm::vec3 e1 = eaves[(s + 1) % 4];
        glm::vec3 fn = glm::normalize(glm::cross(e1 - e0, apex - e0));
        uint32_t a = addV(e0, fn, {0, 0});
        uint32_t b = addV(e1, fn, {1, 0});
        uint32_t c = addV(apex, fn, {0.5f, 1});
        wom.indices.insert(wom.indices.end(), {a, b, c});
    }
    wowee::pipeline::WoweeModel::Batch batch;
    batch.indexStart = 0;
    batch.indexCount = static_cast<uint32_t>(wom.indices.size());
    batch.textureIndex = 0;
    wom.batches.push_back(batch);
    wom.boundMin = glm::vec3(-hx, 0, -hz);
    wom.boundMax = glm::vec3( hx, apexY,  hz);
    if (!wowee::pipeline::WoweeModelLoader::save(wom, womBase)) {
        std::fprintf(stderr,
            "gen-mesh-house: failed to save %s.wom\n", womBase.c_str());
        return 1;
    }
    std::printf("Wrote %s.wom\n", womBase.c_str());
    std::printf("  width      : %.3f\n", width);
    std::printf("  depth      : %.3f\n", depth);
    std::printf("  wall H     : %.3f\n", height);
    std::printf("  roof H     : %.3f (apex %.3f)\n", roofH, apexY);
    std::printf("  vertices   : %zu\n", wom.vertices.size());
    std::printf("  triangles  : %zu\n", wom.indices.size() / 3);
    return 0;
}

int handleFountain(int& i, int argc, char** argv) {
    // Procedural fountain: low cylindrical basin with a
    // narrower spout column rising from its center. Solid
    // basin (not hollow) for simplicity — readable as a
    // fountain because of the spout silhouette. Useful for
    // town squares, plazas, garden centerpieces.
    //
    // The 21st procedural mesh primitive.
    std::string womBase = argv[++i];
    float basinR = 1.5f;
    float basinH = 0.5f;
    float spoutR = 0.2f;
    float spoutH = 1.5f;
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { basinR = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { basinH = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { spoutR = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { spoutH = std::stof(argv[++i]); } catch (...) {}
    }
    if (basinR <= 0 || basinH <= 0 || spoutR <= 0 || spoutH <= 0 ||
        spoutR >= basinR) {
        std::fprintf(stderr,
            "gen-mesh-fountain: all dims > 0; spoutR must be < basinR\n");
        return 1;
    }
    if (womBase.size() >= 4 &&
        womBase.substr(womBase.size() - 4) == ".wom") {
        womBase = womBase.substr(0, womBase.size() - 4);
    }
    wowee::pipeline::WoweeModel wom;
    wom.name = std::filesystem::path(womBase).stem().string();
    wom.version = 3;
    const float pi = 3.14159265358979f;
    const int segs = 24;
    auto addV = [&](glm::vec3 p, glm::vec3 n, glm::vec2 uv) -> uint32_t {
        wowee::pipeline::WoweeModel::Vertex vtx;
        vtx.position = p; vtx.normal = n; vtx.texCoord = uv;
        wom.vertices.push_back(vtx);
        return static_cast<uint32_t>(wom.vertices.size() - 1);
    };
    // Cylinder helper: build side ring + caps from y0 to y1
    // at given radius. Returns when done; indices appended
    // directly. Side ring is 2× (segs+1) verts at y0 then y1.
    auto cylinder = [&](float r, float y0, float y1) {
        uint32_t bot = static_cast<uint32_t>(wom.vertices.size());
        for (int sg = 0; sg <= segs; ++sg) {
            float u = static_cast<float>(sg) / segs;
            float ang = u * 2.0f * pi;
            glm::vec3 p(r * std::cos(ang), y0, r * std::sin(ang));
            glm::vec3 n(std::cos(ang), 0, std::sin(ang));
            addV(p, n, glm::vec2(u, 0));
        }
        uint32_t top = static_cast<uint32_t>(wom.vertices.size());
        for (int sg = 0; sg <= segs; ++sg) {
            float u = static_cast<float>(sg) / segs;
            float ang = u * 2.0f * pi;
            glm::vec3 p(r * std::cos(ang), y1, r * std::sin(ang));
            glm::vec3 n(std::cos(ang), 0, std::sin(ang));
            addV(p, n, glm::vec2(u, 1));
        }
        for (int sg = 0; sg < segs; ++sg) {
            wom.indices.insert(wom.indices.end(), {
                bot + sg, top + sg, bot + sg + 1,
                bot + sg + 1, top + sg, top + sg + 1
            });
        }
        // Top cap (faces +Y)
        uint32_t topC = addV({0, y1, 0}, {0, 1, 0}, {0.5f, 0.5f});
        for (int sg = 0; sg < segs; ++sg) {
            wom.indices.insert(wom.indices.end(),
                {topC, top + sg, top + sg + 1});
        }
        // Bottom cap (faces -Y)
        uint32_t botC = addV({0, y0, 0}, {0, -1, 0}, {0.5f, 0.5f});
        for (int sg = 0; sg < segs; ++sg) {
            wom.indices.insert(wom.indices.end(),
                {botC, bot + sg + 1, bot + sg});
        }
    };
    // Basin: cylinder from y=0 to y=basinH at basinR.
    cylinder(basinR, 0.0f, basinH);
    // Spout: cylinder from y=basinH to y=basinH+spoutH at spoutR.
    cylinder(spoutR, basinH, basinH + spoutH);
    wowee::pipeline::WoweeModel::Batch batch;
    batch.indexStart = 0;
    batch.indexCount = static_cast<uint32_t>(wom.indices.size());
    batch.textureIndex = 0;
    wom.batches.push_back(batch);
    float maxY = basinH + spoutH;
    wom.boundMin = glm::vec3(-basinR, 0,    -basinR);
    wom.boundMax = glm::vec3( basinR, maxY,  basinR);
    if (!wowee::pipeline::WoweeModelLoader::save(wom, womBase)) {
        std::fprintf(stderr,
            "gen-mesh-fountain: failed to save %s.wom\n", womBase.c_str());
        return 1;
    }
    std::printf("Wrote %s.wom\n", womBase.c_str());
    std::printf("  basin    : R=%.3f H=%.3f\n", basinR, basinH);
    std::printf("  spout    : R=%.3f H=%.3f\n", spoutR, spoutH);
    std::printf("  total H  : %.3f\n", maxY);
    std::printf("  vertices : %zu\n", wom.vertices.size());
    std::printf("  triangles: %zu\n", wom.indices.size() / 3);
    return 0;
}

int handleStatue(int& i, int argc, char** argv) {
    // Humanoid placeholder: square pedestal block + tall
    // narrow body cylinder + head sphere. The silhouette
    // reads as a statue without needing limbs. Useful for
    // monuments, hero statues, plaza centerpieces, religious
    // shrines.
    //
    // The 22nd procedural mesh primitive.
    std::string womBase = argv[++i];
    float pedSize = 1.0f;     // pedestal width and depth
    float bodyH = 2.5f;       // body cylinder height
    float headR = 0.4f;       // head sphere radius
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { pedSize = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { bodyH = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { headR = std::stof(argv[++i]); } catch (...) {}
    }
    if (pedSize <= 0 || bodyH <= 0 || headR <= 0) {
        std::fprintf(stderr,
            "gen-mesh-statue: all dims must be positive\n");
        return 1;
    }
    if (womBase.size() >= 4 &&
        womBase.substr(womBase.size() - 4) == ".wom") {
        womBase = womBase.substr(0, womBase.size() - 4);
    }
    wowee::pipeline::WoweeModel wom;
    wom.name = std::filesystem::path(womBase).stem().string();
    wom.version = 3;
    const float pi = 3.14159265358979f;
    auto addV = [&](glm::vec3 p, glm::vec3 n, glm::vec2 uv) -> uint32_t {
        wowee::pipeline::WoweeModel::Vertex vtx;
        vtx.position = p; vtx.normal = n; vtx.texCoord = uv;
        wom.vertices.push_back(vtx);
        return static_cast<uint32_t>(wom.vertices.size() - 1);
    };
    // Pedestal: low square block (24 unique verts).
    float pedH = pedSize * 0.4f;
    float hp = pedSize * 0.5f;
    {
        struct Face { glm::vec3 n, du, dv; };
        Face faces[6] = {
            {{0, 1, 0}, {1, 0, 0}, {0, 0, 1}},
            {{0,-1, 0}, {1, 0, 0}, {0, 0,-1}},
            {{1, 0, 0}, {0, 0, 1}, {0, 1, 0}},
            {{-1,0, 0}, {0, 0,-1}, {0, 1, 0}},
            {{0, 0, 1}, {-1,0, 0}, {0, 1, 0}},
            {{0, 0,-1}, {1, 0, 0}, {0, 1, 0}},
        };
        glm::vec3 c(0, pedH * 0.5f, 0);
        glm::vec3 ext(hp, pedH * 0.5f, hp);
        for (const Face& f : faces) {
            glm::vec3 center = c + glm::vec3(f.n.x*ext.x, f.n.y*ext.y, f.n.z*ext.z);
            glm::vec3 du = glm::vec3(f.du.x*ext.x, f.du.y*ext.y, f.du.z*ext.z);
            glm::vec3 dv = glm::vec3(f.dv.x*ext.x, f.dv.y*ext.y, f.dv.z*ext.z);
            uint32_t base = static_cast<uint32_t>(wom.vertices.size());
            addV(center - du - dv, f.n, {0, 0});
            addV(center + du - dv, f.n, {1, 0});
            addV(center + du + dv, f.n, {1, 1});
            addV(center - du + dv, f.n, {0, 1});
            wom.indices.insert(wom.indices.end(),
                {base, base + 1, base + 2, base, base + 2, base + 3});
        }
    }
    // Body cylinder from y=pedH to y=pedH+bodyH at radius pedSize*0.2
    float bodyR = pedSize * 0.2f;
    float bodyY0 = pedH;
    float bodyY1 = pedH + bodyH;
    const int segs = 16;
    uint32_t bodyBot = static_cast<uint32_t>(wom.vertices.size());
    for (int sg = 0; sg <= segs; ++sg) {
        float u = static_cast<float>(sg) / segs;
        float ang = u * 2.0f * pi;
        glm::vec3 p(bodyR * std::cos(ang), bodyY0, bodyR * std::sin(ang));
        glm::vec3 n(std::cos(ang), 0, std::sin(ang));
        addV(p, n, {u, 0});
    }
    uint32_t bodyTop = static_cast<uint32_t>(wom.vertices.size());
    for (int sg = 0; sg <= segs; ++sg) {
        float u = static_cast<float>(sg) / segs;
        float ang = u * 2.0f * pi;
        glm::vec3 p(bodyR * std::cos(ang), bodyY1, bodyR * std::sin(ang));
        glm::vec3 n(std::cos(ang), 0, std::sin(ang));
        addV(p, n, {u, 1});
    }
    for (int sg = 0; sg < segs; ++sg) {
        wom.indices.insert(wom.indices.end(), {
            bodyBot + sg, bodyTop + sg, bodyBot + sg + 1,
            bodyBot + sg + 1, bodyTop + sg, bodyTop + sg + 1
        });
    }
    // Head sphere centered above body. UV-sphere with 16
    // longitude × 12 latitude segments.
    float headY = bodyY1 + headR;
    const int headLon = 16;
    const int headLat = 12;
    uint32_t headStart = static_cast<uint32_t>(wom.vertices.size());
    for (int la = 0; la <= headLat; ++la) {
        float v = static_cast<float>(la) / headLat;
        float phi = v * pi;  // 0..pi
        float sphi = std::sin(phi), cphi = std::cos(phi);
        for (int lo = 0; lo <= headLon; ++lo) {
            float u = static_cast<float>(lo) / headLon;
            float theta = u * 2.0f * pi;
            glm::vec3 dir(sphi * std::cos(theta),
                          cphi,
                          sphi * std::sin(theta));
            glm::vec3 p = glm::vec3(0, headY, 0) + dir * headR;
            addV(p, dir, {u, v});
        }
    }
    int rowSize = headLon + 1;
    for (int la = 0; la < headLat; ++la) {
        for (int lo = 0; lo < headLon; ++lo) {
            uint32_t i00 = headStart + la * rowSize + lo;
            uint32_t i01 = headStart + la * rowSize + lo + 1;
            uint32_t i10 = headStart + (la + 1) * rowSize + lo;
            uint32_t i11 = headStart + (la + 1) * rowSize + lo + 1;
            wom.indices.insert(wom.indices.end(),
                {i00, i10, i01, i01, i10, i11});
        }
    }
    wowee::pipeline::WoweeModel::Batch batch;
    batch.indexStart = 0;
    batch.indexCount = static_cast<uint32_t>(wom.indices.size());
    batch.textureIndex = 0;
    wom.batches.push_back(batch);
    float maxY = headY + headR;
    wom.boundMin = glm::vec3(-hp, 0,    -hp);
    wom.boundMax = glm::vec3( hp, maxY,  hp);
    if (!wowee::pipeline::WoweeModelLoader::save(wom, womBase)) {
        std::fprintf(stderr,
            "gen-mesh-statue: failed to save %s.wom\n", womBase.c_str());
        return 1;
    }
    std::printf("Wrote %s.wom\n", womBase.c_str());
    std::printf("  pedestal  : %.3f × %.3f × %.3f\n", pedSize, pedH, pedSize);
    std::printf("  body      : R=%.3f H=%.3f\n", bodyR, bodyH);
    std::printf("  head      : R=%.3f\n", headR);
    std::printf("  total H   : %.3f\n", maxY);
    std::printf("  vertices  : %zu\n", wom.vertices.size());
    std::printf("  triangles : %zu\n", wom.indices.size() / 3);
    return 0;
}

int handleAltar(int& i, int argc, char** argv) {
    // Round altar: stack of N stepped cylindrical discs,
    // each one wider and shorter than the next so the
    // silhouette descends like a wedding cake. Top disc is
    // the altar surface (where offerings would go); base
    // discs widen out to anchor the structure visually.
    //
    // The 23rd procedural mesh primitive — pairs naturally
    // with --gen-texture-marble for a temple aesthetic.
    std::string womBase = argv[++i];
    float topR = 0.7f;        // top altar disc radius
    float topH = 0.3f;        // top altar disc height
    int steps = 3;            // base steps below the top
    float stepStride = 0.3f;  // each step grows R by this much, shrinks H
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { topR = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { topH = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { steps = std::stoi(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { stepStride = std::stof(argv[++i]); } catch (...) {}
    }
    if (topR <= 0 || topH <= 0 || steps < 0 || steps > 16 ||
        stepStride <= 0 || stepStride > 5.0f) {
        std::fprintf(stderr,
            "gen-mesh-altar: topR/topH > 0, steps 0..16, stride 0..5\n");
        return 1;
    }
    if (womBase.size() >= 4 &&
        womBase.substr(womBase.size() - 4) == ".wom") {
        womBase = womBase.substr(0, womBase.size() - 4);
    }
    wowee::pipeline::WoweeModel wom;
    wom.name = std::filesystem::path(womBase).stem().string();
    wom.version = 3;
    const float pi = 3.14159265358979f;
    const int segs = 24;
    auto addV = [&](glm::vec3 p, glm::vec3 n, glm::vec2 uv) -> uint32_t {
        wowee::pipeline::WoweeModel::Vertex vtx;
        vtx.position = p; vtx.normal = n; vtx.texCoord = uv;
        wom.vertices.push_back(vtx);
        return static_cast<uint32_t>(wom.vertices.size() - 1);
    };
    // Build a cylindrical disc from y0 to y1 at radius r.
    // Side ring + top cap (faces +Y). Bottom of each disc
    // is hidden by the next disc below, so we skip a bottom
    // cap on all discs except the last (saves ~24 tris/disc).
    auto disc = [&](float r, float y0, float y1, bool capBottom) {
        uint32_t bot = static_cast<uint32_t>(wom.vertices.size());
        for (int sg = 0; sg <= segs; ++sg) {
            float u = static_cast<float>(sg) / segs;
            float ang = u * 2.0f * pi;
            glm::vec3 p(r * std::cos(ang), y0, r * std::sin(ang));
            glm::vec3 n(std::cos(ang), 0, std::sin(ang));
            addV(p, n, {u, 0});
        }
        uint32_t top = static_cast<uint32_t>(wom.vertices.size());
        for (int sg = 0; sg <= segs; ++sg) {
            float u = static_cast<float>(sg) / segs;
            float ang = u * 2.0f * pi;
            glm::vec3 p(r * std::cos(ang), y1, r * std::sin(ang));
            glm::vec3 n(std::cos(ang), 0, std::sin(ang));
            addV(p, n, {u, 1});
        }
        for (int sg = 0; sg < segs; ++sg) {
            wom.indices.insert(wom.indices.end(), {
                bot + sg, top + sg, bot + sg + 1,
                bot + sg + 1, top + sg, top + sg + 1
            });
        }
        // Top cap fan (faces +Y).
        uint32_t tc = addV({0, y1, 0}, {0, 1, 0}, {0.5f, 0.5f});
        for (int sg = 0; sg < segs; ++sg) {
            wom.indices.insert(wom.indices.end(),
                {tc, top + sg, top + sg + 1});
        }
        if (capBottom) {
            uint32_t bc = addV({0, y0, 0}, {0, -1, 0}, {0.5f, 0.5f});
            for (int sg = 0; sg < segs; ++sg) {
                wom.indices.insert(wom.indices.end(),
                    {bc, bot + sg + 1, bot + sg});
            }
        }
    };
    // Build bottom-up so y0 starts at floor and tops stack.
    // Step k (k=0 is bottom-most) has radius = topR + (steps-k)*stride
    // and height = topH * (1 - 0.2 * k). Y position accumulates.
    float curY = 0.0f;
    for (int k = steps - 1; k >= 0; --k) {  // bottom step first
        float r = topR + (k + 1) * stepStride;
        float h = topH * (1.0f - 0.2f * k);
        if (h < topH * 0.4f) h = topH * 0.4f;
        bool isBottom = (k == steps - 1);
        disc(r, curY, curY + h, isBottom);
        curY += h;
    }
    // Top disc (the actual altar surface)
    disc(topR, curY, curY + topH, steps == 0);
    float maxY = curY + topH;
    wowee::pipeline::WoweeModel::Batch batch;
    batch.indexStart = 0;
    batch.indexCount = static_cast<uint32_t>(wom.indices.size());
    batch.textureIndex = 0;
    wom.batches.push_back(batch);
    float maxR = topR + steps * stepStride;
    wom.boundMin = glm::vec3(-maxR, 0,    -maxR);
    wom.boundMax = glm::vec3( maxR, maxY,  maxR);
    if (!wowee::pipeline::WoweeModelLoader::save(wom, womBase)) {
        std::fprintf(stderr,
            "gen-mesh-altar: failed to save %s.wom\n", womBase.c_str());
        return 1;
    }
    std::printf("Wrote %s.wom\n", womBase.c_str());
    std::printf("  top      : R=%.3f H=%.3f\n", topR, topH);
    std::printf("  steps    : %d (stride %.3f)\n", steps, stepStride);
    std::printf("  base R   : %.3f\n", maxR);
    std::printf("  total H  : %.3f\n", maxY);
    std::printf("  vertices : %zu\n", wom.vertices.size());
    std::printf("  triangles: %zu\n", wom.indices.size() / 3);
    return 0;
}

int handlePortal(int& i, int argc, char** argv) {
    // Doorway portal: two vertical post boxes plus a
    // horizontal lintel box across the top. Posts run along
    // the Z axis (so width spans Z), opening faces +X. The
    // gap between the posts is the actual doorway. Useful
    // for entrances, gates, magical portals, ruins.
    //
    // The 24th procedural mesh primitive.
    std::string womBase = argv[++i];
    float width = 2.5f;          // outer-to-outer along Z
    float height = 4.0f;         // total Y
    float postThick = 0.4f;      // post width in X and Z
    float lintelH = 0.5f;        // top lintel height (Y)
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { width = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { height = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { postThick = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { lintelH = std::stof(argv[++i]); } catch (...) {}
    }
    if (width <= 0 || height <= 0 || postThick <= 0 ||
        lintelH < 0 || postThick * 2 >= width ||
        lintelH > height) {
        std::fprintf(stderr,
            "gen-mesh-portal: posts must fit inside width; lintel <= height\n");
        return 1;
    }
    if (womBase.size() >= 4 &&
        womBase.substr(womBase.size() - 4) == ".wom") {
        womBase = womBase.substr(0, womBase.size() - 4);
    }
    wowee::pipeline::WoweeModel wom;
    wom.name = std::filesystem::path(womBase).stem().string();
    wom.version = 3;
    // Box helper — same pattern as other multi-box meshes.
    auto addBox = [&](float cx, float cy, float cz,
                      float hx, float hy, float hz) {
        struct Face { glm::vec3 n, du, dv; };
        Face faces[6] = {
            {{0, 1, 0}, {1, 0, 0}, {0, 0, 1}},
            {{0,-1, 0}, {1, 0, 0}, {0, 0,-1}},
            {{1, 0, 0}, {0, 0, 1}, {0, 1, 0}},
            {{-1,0, 0}, {0, 0,-1}, {0, 1, 0}},
            {{0, 0, 1}, {-1,0, 0}, {0, 1, 0}},
            {{0, 0,-1}, {1, 0, 0}, {0, 1, 0}},
        };
        glm::vec3 c(cx, cy, cz);
        glm::vec3 ext(hx, hy, hz);
        for (const Face& f : faces) {
            glm::vec3 center = c + glm::vec3(f.n.x*hx, f.n.y*hy, f.n.z*hz);
            glm::vec3 du = glm::vec3(f.du.x*ext.x, f.du.y*ext.y, f.du.z*ext.z);
            glm::vec3 dv = glm::vec3(f.dv.x*ext.x, f.dv.y*ext.y, f.dv.z*ext.z);
            uint32_t base = static_cast<uint32_t>(wom.vertices.size());
            auto push = [&](glm::vec3 p, float u, float v) {
                wowee::pipeline::WoweeModel::Vertex vtx;
                vtx.position = p;
                vtx.normal = f.n;
                vtx.texCoord = {u, v};
                wom.vertices.push_back(vtx);
            };
            push(center - du - dv, 0, 0);
            push(center + du - dv, 1, 0);
            push(center + du + dv, 1, 1);
            push(center - du + dv, 0, 1);
            wom.indices.insert(wom.indices.end(),
                {base, base + 1, base + 2, base, base + 2, base + 3});
        }
    };
    // Two posts at z = ±(width/2 - postThick/2). Each
    // post extends from y=0 to y=height-lintelH so it
    // tucks under the lintel.
    float postY = (height - lintelH) * 0.5f;
    float postHy = (height - lintelH) * 0.5f;
    float postZ = (width - postThick) * 0.5f;
    float postHt = postThick * 0.5f;
    addBox(0, postY,  postZ, postHt, postHy, postHt);
    addBox(0, postY, -postZ, postHt, postHy, postHt);
    // Lintel: spans full width across the top, same X
    // thickness as posts.
    if (lintelH > 0.0f) {
        float lintelY = height - lintelH * 0.5f;
        addBox(0, lintelY, 0,
               postHt, lintelH * 0.5f, width * 0.5f);
    }
    wowee::pipeline::WoweeModel::Batch batch;
    batch.indexStart = 0;
    batch.indexCount = static_cast<uint32_t>(wom.indices.size());
    batch.textureIndex = 0;
    wom.batches.push_back(batch);
    wom.boundMin = glm::vec3(-postHt, 0,      -width * 0.5f);
    wom.boundMax = glm::vec3( postHt, height,  width * 0.5f);
    if (!wowee::pipeline::WoweeModelLoader::save(wom, womBase)) {
        std::fprintf(stderr,
            "gen-mesh-portal: failed to save %s.wom\n", womBase.c_str());
        return 1;
    }
    std::printf("Wrote %s.wom\n", womBase.c_str());
    std::printf("  width      : %.3f\n", width);
    std::printf("  height     : %.3f\n", height);
    std::printf("  post thick : %.3f\n", postThick);
    std::printf("  lintel H   : %.3f%s\n", lintelH,
                lintelH > 0 ? "" : " (no lintel)");
    std::printf("  vertices   : %zu\n", wom.vertices.size());
    std::printf("  triangles  : %zu\n", wom.indices.size() / 3);
    return 0;
}

int handleArchway(int& i, int argc, char** argv) {
    // Semicircular arched doorway. Two cylindrical pillars
    // hold up a curved keystone vault: the vault is a series
    // of N angular wedge segments tracing a half-circle from
    // pillar-top to pillar-top. The opening is the empty
    // semicircular space below.
    //
    // The 25th procedural mesh primitive — the "fancier"
    // sibling of --gen-mesh-portal which uses a flat lintel.
    std::string womBase = argv[++i];
    float width = 3.0f;        // outer-to-outer pillar centers along Z
    float pillarH = 3.0f;      // pillar height (Y)
    float thickness = 0.4f;    // pillar radius and arch radial thickness
    int archSegs = 12;         // segments around the half-circle
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { width = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { pillarH = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { thickness = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { archSegs = std::stoi(argv[++i]); } catch (...) {}
    }
    if (width <= 0 || pillarH <= 0 || thickness <= 0 ||
        archSegs < 4 || archSegs > 64 ||
        thickness * 4 >= width) {
        std::fprintf(stderr,
            "gen-mesh-archway: thickness×4 < width, archSegs 4..64\n");
        return 1;
    }
    if (womBase.size() >= 4 &&
        womBase.substr(womBase.size() - 4) == ".wom") {
        womBase = womBase.substr(0, womBase.size() - 4);
    }
    wowee::pipeline::WoweeModel wom;
    wom.name = std::filesystem::path(womBase).stem().string();
    wom.version = 3;
    const float pi = 3.14159265358979f;
    const int pillarSegs = 16;
    auto addV = [&](glm::vec3 p, glm::vec3 n, glm::vec2 uv) -> uint32_t {
        wowee::pipeline::WoweeModel::Vertex vtx;
        vtx.position = p; vtx.normal = n; vtx.texCoord = uv;
        wom.vertices.push_back(vtx);
        return static_cast<uint32_t>(wom.vertices.size() - 1);
    };
    // Cylindrical pillar at given (cx, cz), from y=0 to y=pillarH.
    auto pillar = [&](float cx, float cz) {
        float r = thickness;
        uint32_t bot = static_cast<uint32_t>(wom.vertices.size());
        for (int sg = 0; sg <= pillarSegs; ++sg) {
            float u = static_cast<float>(sg) / pillarSegs;
            float ang = u * 2.0f * pi;
            glm::vec3 p(cx + r * std::cos(ang), 0,
                        cz + r * std::sin(ang));
            glm::vec3 n(std::cos(ang), 0, std::sin(ang));
            addV(p, n, {u, 0});
        }
        uint32_t top = static_cast<uint32_t>(wom.vertices.size());
        for (int sg = 0; sg <= pillarSegs; ++sg) {
            float u = static_cast<float>(sg) / pillarSegs;
            float ang = u * 2.0f * pi;
            glm::vec3 p(cx + r * std::cos(ang), pillarH,
                        cz + r * std::sin(ang));
            glm::vec3 n(std::cos(ang), 0, std::sin(ang));
            addV(p, n, {u, 1});
        }
        for (int sg = 0; sg < pillarSegs; ++sg) {
            wom.indices.insert(wom.indices.end(), {
                bot + sg, top + sg, bot + sg + 1,
                bot + sg + 1, top + sg, top + sg + 1
            });
        }
        // Caps
        uint32_t bc = addV({cx, 0, cz}, {0, -1, 0}, {0.5f, 0.5f});
        uint32_t tc = addV({cx, pillarH, cz}, {0, 1, 0}, {0.5f, 0.5f});
        for (int sg = 0; sg < pillarSegs; ++sg) {
            wom.indices.insert(wom.indices.end(),
                {bc, bot + sg + 1, bot + sg});
            wom.indices.insert(wom.indices.end(),
                {tc, top + sg, top + sg + 1});
        }
    };
    float pillarZ = (width - 2 * thickness) * 0.5f;
    pillar(0,  pillarZ);
    pillar(0, -pillarZ);
    // Arch vault: trace half-circle from (z = +pillarZ, y = pillarH)
    // up over to (z = -pillarZ, y = pillarH). Center of arch:
    // (z = 0, y = pillarH). Arch radius = pillarZ.
    // Inner arch (radius pillarZ - thickness*0.5) and outer
    // (radius pillarZ + thickness*0.5) — the vault sits between.
    float archCY = pillarH;
    float arcInner = pillarZ - thickness * 0.5f;
    float arcOuter = pillarZ + thickness * 0.5f;
    // Each segment: 4 verts (inner-near, outer-near, inner-far,
    // outer-far) extruded along X by thickness so the vault
    // has front and back faces.
    float archX = thickness * 0.5f;  // half-depth in X
    // Build vertex rings for inner and outer surfaces at
    // each segment boundary, then connect.
    // Top half-circle goes from theta=0 to theta=pi.
    std::vector<glm::vec3> innerRing;
    std::vector<glm::vec3> outerRing;
    for (int s = 0; s <= archSegs; ++s) {
        float t = static_cast<float>(s) / archSegs;
        float theta = t * pi;  // 0..pi
        float zi = arcInner * std::cos(theta);
        float yi = arcInner * std::sin(theta);
        float zo = arcOuter * std::cos(theta);
        float yo = arcOuter * std::sin(theta);
        innerRing.push_back({0, archCY + yi, zi});
        outerRing.push_back({0, archCY + yo, zo});
    }
    // For each segment, add 8 vertices (4 corners × front/back face)
    // and stitch them into 6 quads = 12 tris each.
    for (int s = 0; s < archSegs; ++s) {
        glm::vec3 i0 = innerRing[s];
        glm::vec3 i1 = innerRing[s + 1];
        glm::vec3 o0 = outerRing[s];
        glm::vec3 o1 = outerRing[s + 1];
        // Estimate outward (radial) normal as midpoint of o0+o1
        // direction from center.
        glm::vec3 outDir = glm::normalize(glm::vec3(0,
            (i0.y + i1.y + o0.y + o1.y) * 0.25f - archCY,
            (i0.z + i1.z + o0.z + o1.z) * 0.25f));
        glm::vec3 frontN(1, 0, 0);
        glm::vec3 backN(-1, 0, 0);
        auto V = [&](glm::vec3 p, glm::vec3 n) {
            return addV(p, n, {0, 0});
        };
        // Outer surface (top of arch): faces outward radially
        uint32_t a = V({-archX, o0.y, o0.z}, outDir);
        uint32_t b = V({ archX, o0.y, o0.z}, outDir);
        uint32_t c = V({ archX, o1.y, o1.z}, outDir);
        uint32_t d = V({-archX, o1.y, o1.z}, outDir);
        wom.indices.insert(wom.indices.end(), {a, b, c, a, c, d});
        // Inner surface (underside of arch): faces inward
        uint32_t e = V({-archX, i0.y, i0.z}, -outDir);
        uint32_t f = V({ archX, i0.y, i0.z}, -outDir);
        uint32_t g = V({ archX, i1.y, i1.z}, -outDir);
        uint32_t h = V({-archX, i1.y, i1.z}, -outDir);
        wom.indices.insert(wom.indices.end(), {e, g, f, e, h, g});
        // Front face (+X) of this wedge
        uint32_t fi0 = V({ archX, i0.y, i0.z}, frontN);
        uint32_t fo0 = V({ archX, o0.y, o0.z}, frontN);
        uint32_t fo1 = V({ archX, o1.y, o1.z}, frontN);
        uint32_t fi1 = V({ archX, i1.y, i1.z}, frontN);
        wom.indices.insert(wom.indices.end(),
            {fi0, fo0, fo1, fi0, fo1, fi1});
        // Back face (-X)
        uint32_t bi0 = V({-archX, i0.y, i0.z}, backN);
        uint32_t bo0 = V({-archX, o0.y, o0.z}, backN);
        uint32_t bo1 = V({-archX, o1.y, o1.z}, backN);
        uint32_t bi1 = V({-archX, i1.y, i1.z}, backN);
        wom.indices.insert(wom.indices.end(),
            {bi0, bo1, bo0, bi0, bi1, bo1});
    }
    wowee::pipeline::WoweeModel::Batch batch;
    batch.indexStart = 0;
    batch.indexCount = static_cast<uint32_t>(wom.indices.size());
    batch.textureIndex = 0;
    wom.batches.push_back(batch);
    float maxY = pillarH + arcOuter;
    wom.boundMin = glm::vec3(-thickness, 0,    -width * 0.5f);
    wom.boundMax = glm::vec3( thickness, maxY,  width * 0.5f);
    if (!wowee::pipeline::WoweeModelLoader::save(wom, womBase)) {
        std::fprintf(stderr,
            "gen-mesh-archway: failed to save %s.wom\n", womBase.c_str());
        return 1;
    }
    std::printf("Wrote %s.wom\n", womBase.c_str());
    std::printf("  width      : %.3f\n", width);
    std::printf("  pillar H   : %.3f\n", pillarH);
    std::printf("  thickness  : %.3f\n", thickness);
    std::printf("  arch segs  : %d (radius %.3f)\n", archSegs, arcOuter);
    std::printf("  apex Y     : %.3f\n", maxY);
    std::printf("  vertices   : %zu\n", wom.vertices.size());
    std::printf("  triangles  : %zu\n", wom.indices.size() / 3);
    return 0;
}

int handleBarrel(int& i, int argc, char** argv) {
    // Tapered barrel: cylindrical body whose radius bulges
    // smoothly from `topRadius` at the rims to `midRadius`
    // at the middle (the classic stave-cooper barrel
    // silhouette), plus 2 raised hoop bands at 25% and 75%
    // of the height. The 26th procedural mesh primitive.
    std::string womBase = argv[++i];
    float topR = 0.4f;        // radius at top and bottom rim
    float midR = 0.5f;        // radius at the middle bulge
    float height = 1.0f;
    float hoopThick = 0.06f;  // hoop band radial protrusion
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { topR = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { midR = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { height = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { hoopThick = std::stof(argv[++i]); } catch (...) {}
    }
    if (topR <= 0 || midR <= 0 || height <= 0 ||
        hoopThick < 0 || hoopThick > 0.5f) {
        std::fprintf(stderr,
            "gen-mesh-barrel: radii/height > 0, hoopThick 0..0.5\n");
        return 1;
    }
    if (womBase.size() >= 4 &&
        womBase.substr(womBase.size() - 4) == ".wom") {
        womBase = womBase.substr(0, womBase.size() - 4);
    }
    wowee::pipeline::WoweeModel wom;
    wom.name = std::filesystem::path(womBase).stem().string();
    wom.version = 3;
    const float pi = 3.14159265358979f;
    const int segs = 16;        // angular subdivisions
    const int rings = 12;       // vertical slices
    auto addV = [&](glm::vec3 p, glm::vec3 n, glm::vec2 uv) -> uint32_t {
        wowee::pipeline::WoweeModel::Vertex vtx;
        vtx.position = p; vtx.normal = n; vtx.texCoord = uv;
        wom.vertices.push_back(vtx);
        return static_cast<uint32_t>(wom.vertices.size() - 1);
    };
    // Radius profile: smooth cosine bulge from rim to mid.
    // r(t) = topR + (midR - topR) * sin(pi*t) where t in 0..1
    // gives 0 at t=0/1 and 1 at t=0.5 — exact rim fit.
    auto radiusAt = [&](float t) -> float {
        return topR + (midR - topR) * std::sin(pi * t);
    };
    uint32_t firstRing = static_cast<uint32_t>(wom.vertices.size());
    for (int ri = 0; ri <= rings; ++ri) {
        float t = static_cast<float>(ri) / rings;
        float y = t * height;
        float r = radiusAt(t);
        // Hoops: bump radius outward in two narrow bands.
        float hoop1 = std::abs(t - 0.25f);
        float hoop2 = std::abs(t - 0.75f);
        if (hoop1 < 0.04f) r += hoopThick * (1.0f - hoop1 / 0.04f);
        if (hoop2 < 0.04f) r += hoopThick * (1.0f - hoop2 / 0.04f);
        for (int sg = 0; sg <= segs; ++sg) {
            float u = static_cast<float>(sg) / segs;
            float ang = u * 2.0f * pi;
            glm::vec3 p(r * std::cos(ang), y, r * std::sin(ang));
            glm::vec3 n(std::cos(ang), 0, std::sin(ang));
            addV(p, n, {u, t});
        }
    }
    int rowSize = segs + 1;
    for (int ri = 0; ri < rings; ++ri) {
        for (int sg = 0; sg < segs; ++sg) {
            uint32_t i00 = firstRing + ri * rowSize + sg;
            uint32_t i01 = firstRing + ri * rowSize + sg + 1;
            uint32_t i10 = firstRing + (ri + 1) * rowSize + sg;
            uint32_t i11 = firstRing + (ri + 1) * rowSize + sg + 1;
            wom.indices.insert(wom.indices.end(),
                {i00, i10, i01, i01, i10, i11});
        }
    }
    // End caps (top + bottom). topR is also the bottom-most
    // and top-most ring radius since sin(0) = sin(pi) = 0.
    uint32_t botCenter = addV({0, 0, 0}, {0, -1, 0}, {0.5f, 0.5f});
    uint32_t topCenter = addV({0, height, 0}, {0, 1, 0}, {0.5f, 0.5f});
    uint32_t botRing = firstRing;
    uint32_t topRing = firstRing + rings * rowSize;
    for (int sg = 0; sg < segs; ++sg) {
        wom.indices.insert(wom.indices.end(),
            {botCenter, botRing + sg + 1, botRing + sg});
        wom.indices.insert(wom.indices.end(),
            {topCenter, topRing + sg, topRing + sg + 1});
    }
    wowee::pipeline::WoweeModel::Batch batch;
    batch.indexStart = 0;
    batch.indexCount = static_cast<uint32_t>(wom.indices.size());
    batch.textureIndex = 0;
    wom.batches.push_back(batch);
    float maxR = midR + hoopThick;
    wom.boundMin = glm::vec3(-maxR, 0,    -maxR);
    wom.boundMax = glm::vec3( maxR, height, maxR);
    if (!wowee::pipeline::WoweeModelLoader::save(wom, womBase)) {
        std::fprintf(stderr,
            "gen-mesh-barrel: failed to save %s.wom\n", womBase.c_str());
        return 1;
    }
    std::printf("Wrote %s.wom\n", womBase.c_str());
    std::printf("  rim R     : %.3f\n", topR);
    std::printf("  bulge R   : %.3f\n", midR);
    std::printf("  height    : %.3f\n", height);
    std::printf("  hoops     : 2 (thickness %.3f)\n", hoopThick);
    std::printf("  vertices  : %zu\n", wom.vertices.size());
    std::printf("  triangles : %zu\n", wom.indices.size() / 3);
    return 0;
}

int handleChest(int& i, int argc, char** argv) {
    // Treasure chest: rectangular body box + smaller lid
    // box on top + 3 thin iron bands wrapping around the
    // body + a small lock plate on the front center face.
    // The 27th procedural mesh primitive — useful for
    // dungeon loot, room decoration, quest objectives.
    std::string womBase = argv[++i];
    float width = 1.4f;       // along X
    float depth = 0.9f;       // along Z
    float bodyH = 0.9f;       // body box height
    float lidH = 0.25f;       // lid height above body
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { width = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { depth = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { bodyH = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { lidH = std::stof(argv[++i]); } catch (...) {}
    }
    if (width <= 0 || depth <= 0 || bodyH <= 0 || lidH < 0) {
        std::fprintf(stderr,
            "gen-mesh-chest: width/depth/bodyH > 0, lidH >= 0\n");
        return 1;
    }
    if (womBase.size() >= 4 &&
        womBase.substr(womBase.size() - 4) == ".wom") {
        womBase = womBase.substr(0, womBase.size() - 4);
    }
    wowee::pipeline::WoweeModel wom;
    wom.name = std::filesystem::path(womBase).stem().string();
    wom.version = 3;
    // Box helper — adds 24 unique verts / 12 tris centered
    // on (cx, cy, cz) with half-extents (hx, hy, hz). Each
    // face gets unique normals for flat shading.
    auto addBox = [&](float cx, float cy, float cz,
                      float hx, float hy, float hz) {
        struct Face { glm::vec3 n, du, dv; };
        Face faces[6] = {
            {{0, 1, 0}, {1, 0, 0}, {0, 0, 1}},
            {{0,-1, 0}, {1, 0, 0}, {0, 0,-1}},
            {{1, 0, 0}, {0, 0, 1}, {0, 1, 0}},
            {{-1,0, 0}, {0, 0,-1}, {0, 1, 0}},
            {{0, 0, 1}, {-1,0, 0}, {0, 1, 0}},
            {{0, 0,-1}, {1, 0, 0}, {0, 1, 0}},
        };
        glm::vec3 c(cx, cy, cz);
        glm::vec3 ext(hx, hy, hz);
        for (const Face& f : faces) {
            glm::vec3 center = c + glm::vec3(f.n.x*hx, f.n.y*hy, f.n.z*hz);
            glm::vec3 du = glm::vec3(f.du.x*ext.x, f.du.y*ext.y, f.du.z*ext.z);
            glm::vec3 dv = glm::vec3(f.dv.x*ext.x, f.dv.y*ext.y, f.dv.z*ext.z);
            uint32_t base = static_cast<uint32_t>(wom.vertices.size());
            auto push = [&](glm::vec3 p, float u, float v) {
                wowee::pipeline::WoweeModel::Vertex vtx;
                vtx.position = p; vtx.normal = f.n; vtx.texCoord = {u, v};
                wom.vertices.push_back(vtx);
            };
            push(center - du - dv, 0, 0);
            push(center + du - dv, 1, 0);
            push(center + du + dv, 1, 1);
            push(center - du + dv, 0, 1);
            wom.indices.insert(wom.indices.end(),
                {base, base + 1, base + 2, base, base + 2, base + 3});
        }
    };
    float hx = width * 0.5f;
    float hz = depth * 0.5f;
    // Body: y=0 to y=bodyH
    addBox(0, bodyH * 0.5f, 0, hx, bodyH * 0.5f, hz);
    // Lid: smaller box on top, slightly inset on each side
    float lidInset = std::min(width, depth) * 0.04f;
    float lidHx = hx - lidInset;
    float lidHz = hz - lidInset;
    if (lidH > 0.0f && lidHx > 0 && lidHz > 0) {
        addBox(0, bodyH + lidH * 0.5f, 0,
               lidHx, lidH * 0.5f, lidHz);
    }
    // 3 iron bands wrapping the body — thin slabs
    // protruding ~3% radially on the sides + top.
    // Band positions: 15%, 50%, 85% of body width.
    float bandThickX = width * 0.04f;  // band depth along X
    float bandHy = bodyH * 0.5f + 0.005f;
    float bandHz = hz + 0.012f;
    float bandPositions[3] = {-hx * 0.7f, 0.0f, hx * 0.7f};
    for (float bx : bandPositions) {
        addBox(bx, bandHy, 0,
               bandThickX * 0.5f, bandHy, bandHz);
    }
    // Lock plate: small thin box on the front face, centered.
    // Front face is +Z. Plate sits at z = hz + tiny epsilon.
    float lockW = width * 0.10f;
    float lockH = bodyH * 0.18f;
    float lockY = bodyH * 0.65f;
    float lockEps = 0.008f;
    addBox(0, lockY, hz + lockEps,
           lockW * 0.5f, lockH * 0.5f, lockEps);
    wowee::pipeline::WoweeModel::Batch batch;
    batch.indexStart = 0;
    batch.indexCount = static_cast<uint32_t>(wom.indices.size());
    batch.textureIndex = 0;
    wom.batches.push_back(batch);
    float maxY = bodyH + lidH;
    wom.boundMin = glm::vec3(-hx, 0, -hz - 0.012f);
    wom.boundMax = glm::vec3( hx, maxY, hz + 0.012f);
    if (!wowee::pipeline::WoweeModelLoader::save(wom, womBase)) {
        std::fprintf(stderr,
            "gen-mesh-chest: failed to save %s.wom\n", womBase.c_str());
        return 1;
    }
    std::printf("Wrote %s.wom\n", womBase.c_str());
    std::printf("  width × depth : %.3f × %.3f\n", width, depth);
    std::printf("  body H        : %.3f\n", bodyH);
    std::printf("  lid H         : %.3f\n", lidH);
    std::printf("  components    : body + lid + 3 bands + lock\n");
    std::printf("  vertices      : %zu\n", wom.vertices.size());
    std::printf("  triangles     : %zu\n", wom.indices.size() / 3);
    return 0;
}

int handleAnvil(int& i, int argc, char** argv) {
    // Blacksmith anvil: stepped pedestal base + flat work
    // surface (the "face") + tapered horn extending forward.
    // Built from 3 boxes + a 4-vertex tapered prism for the
    // horn. The 28th procedural mesh primitive.
    std::string womBase = argv[++i];
    float length = 1.0f;       // along X (face length)
    float width = 0.4f;        // along Z
    float hornLen = 0.5f;      // horn extending past face
    float bodyH = 0.5f;        // total height
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { length = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { width = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { hornLen = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { bodyH = std::stof(argv[++i]); } catch (...) {}
    }
    if (length <= 0 || width <= 0 || hornLen < 0 || bodyH <= 0) {
        std::fprintf(stderr,
            "gen-mesh-anvil: length/width/bodyH > 0, hornLen >= 0\n");
        return 1;
    }
    if (womBase.size() >= 4 &&
        womBase.substr(womBase.size() - 4) == ".wom") {
        womBase = womBase.substr(0, womBase.size() - 4);
    }
    wowee::pipeline::WoweeModel wom;
    wom.name = std::filesystem::path(womBase).stem().string();
    wom.version = 3;
    auto addBox = [&](float cx, float cy, float cz,
                      float hx, float hy, float hz) {
        struct Face { glm::vec3 n, du, dv; };
        Face faces[6] = {
            {{0, 1, 0}, {1, 0, 0}, {0, 0, 1}},
            {{0,-1, 0}, {1, 0, 0}, {0, 0,-1}},
            {{1, 0, 0}, {0, 0, 1}, {0, 1, 0}},
            {{-1,0, 0}, {0, 0,-1}, {0, 1, 0}},
            {{0, 0, 1}, {-1,0, 0}, {0, 1, 0}},
            {{0, 0,-1}, {1, 0, 0}, {0, 1, 0}},
        };
        glm::vec3 c(cx, cy, cz);
        glm::vec3 ext(hx, hy, hz);
        for (const Face& f : faces) {
            glm::vec3 center = c + glm::vec3(f.n.x*hx, f.n.y*hy, f.n.z*hz);
            glm::vec3 du = glm::vec3(f.du.x*ext.x, f.du.y*ext.y, f.du.z*ext.z);
            glm::vec3 dv = glm::vec3(f.dv.x*ext.x, f.dv.y*ext.y, f.dv.z*ext.z);
            uint32_t base = static_cast<uint32_t>(wom.vertices.size());
            auto push = [&](glm::vec3 p, float u, float v) {
                wowee::pipeline::WoweeModel::Vertex vtx;
                vtx.position = p; vtx.normal = f.n; vtx.texCoord = {u, v};
                wom.vertices.push_back(vtx);
            };
            push(center - du - dv, 0, 0);
            push(center + du - dv, 1, 0);
            push(center + du + dv, 1, 1);
            push(center - du + dv, 0, 1);
            wom.indices.insert(wom.indices.end(),
                {base, base + 1, base + 2, base, base + 2, base + 3});
        }
    };
    // Pedestal: bottom 60% of total height, narrower base
    // (4-step taper would be classic but for simplicity we use
    // a wide base + narrow waist + wide cap structure as 3 boxes).
    float baseH = bodyH * 0.25f;
    float waistH = bodyH * 0.30f;
    float capH = bodyH * 0.20f;
    float faceH = bodyH * 0.25f;
    float baseHx = length * 0.45f;
    float baseHz = width * 0.55f;
    float waistHx = length * 0.30f;
    float waistHz = width * 0.40f;
    float capHx = length * 0.50f;
    float capHz = width * 0.55f;
    float faceHx = length * 0.50f;
    float faceHz = width * 0.50f;
    float y0 = 0.0f;
    addBox(0, y0 + baseH * 0.5f, 0, baseHx, baseH * 0.5f, baseHz);
    y0 += baseH;
    addBox(0, y0 + waistH * 0.5f, 0, waistHx, waistH * 0.5f, waistHz);
    y0 += waistH;
    addBox(0, y0 + capH * 0.5f, 0, capHx, capH * 0.5f, capHz);
    y0 += capH;
    addBox(0, y0 + faceH * 0.5f, 0, faceHx, faceH * 0.5f, faceHz);
    // Horn: tapered prism extending in +X past the face. 6 verts
    // (rectangle at face edge tapering to a point at the tip).
    if (hornLen > 0.0f) {
        float hornBaseX = faceHx;
        float hornTipX = faceHx + hornLen;
        float hornY0 = y0 + faceH * 0.25f;
        float hornY1 = y0 + faceH * 0.75f;
        float hornHz = faceHz * 0.6f;
        // 4 base verts + 2 tip verts (tip is a vertical edge)
        // Build 4 face triangles + 2 base/tip caps
        glm::vec3 b00(hornBaseX, hornY0,  hornHz);
        glm::vec3 b01(hornBaseX, hornY0, -hornHz);
        glm::vec3 b10(hornBaseX, hornY1,  hornHz);
        glm::vec3 b11(hornBaseX, hornY1, -hornHz);
        glm::vec3 t0 (hornTipX,  (hornY0 + hornY1) * 0.5f,  0);
        // Top face triangles (b10, b11, t0)
        auto addTri = [&](glm::vec3 a, glm::vec3 b, glm::vec3 c) {
            glm::vec3 n = glm::normalize(glm::cross(b - a, c - a));
            uint32_t base = static_cast<uint32_t>(wom.vertices.size());
            wom.vertices.push_back({a, n, {0, 0}});
            wom.vertices.push_back({b, n, {1, 0}});
            wom.vertices.push_back({c, n, {0.5f, 1}});
            wom.indices.insert(wom.indices.end(), {base, base + 1, base + 2});
        };
        // 4 side faces converging to t0
        addTri(b00, b01, t0);          // bottom
        addTri(b11, b10, t0);          // top
        addTri(b10, b00, t0);          // +Z side
        addTri(b01, b11, t0);          // -Z side
        // Base of horn (closes the rectangle on the face side).
        // The base is hidden against the anvil face but include it
        // so the mesh is watertight.
        glm::vec3 baseN(-1, 0, 0);
        uint32_t base = static_cast<uint32_t>(wom.vertices.size());
        wom.vertices.push_back({b00, baseN, {0, 0}});
        wom.vertices.push_back({b10, baseN, {0, 1}});
        wom.vertices.push_back({b11, baseN, {1, 1}});
        wom.vertices.push_back({b01, baseN, {1, 0}});
        wom.indices.insert(wom.indices.end(),
            {base, base + 1, base + 2, base, base + 2, base + 3});
    }
    wowee::pipeline::WoweeModel::Batch batch;
    batch.indexStart = 0;
    batch.indexCount = static_cast<uint32_t>(wom.indices.size());
    batch.textureIndex = 0;
    wom.batches.push_back(batch);
    float maxX = std::max(faceHx, faceHx + hornLen);
    float maxZ = std::max({baseHz, waistHz, capHz, faceHz});
    wom.boundMin = glm::vec3(-faceHx, 0, -maxZ);
    wom.boundMax = glm::vec3( maxX, bodyH, maxZ);
    if (!wowee::pipeline::WoweeModelLoader::save(wom, womBase)) {
        std::fprintf(stderr,
            "gen-mesh-anvil: failed to save %s.wom\n", womBase.c_str());
        return 1;
    }
    std::printf("Wrote %s.wom\n", womBase.c_str());
    std::printf("  length × width : %.3f × %.3f\n", length, width);
    std::printf("  body H         : %.3f\n", bodyH);
    std::printf("  horn length    : %.3f\n", hornLen);
    std::printf("  components     : 4 step pedestal + tapered horn\n");
    std::printf("  vertices       : %zu\n", wom.vertices.size());
    std::printf("  triangles      : %zu\n", wom.indices.size() / 3);
    return 0;
}


int handleStairs(int& i, int argc, char** argv) {
    // Procedural straight staircase along +X. N steps with
    // configurable rise/run/width. Each step is a closed
    // box, sharing no vertices with neighbors so per-face
    // normals are flat (looks correct without smoothing).
    //
    // Defaults: 5 steps, stepHeight=0.2, stepDepth=0.3,
    // width=1.0 — roughly 1m tall × 1.5m long × 1m wide,
    // a believable single flight.
    //
    // Useful for level-design placeholders ("I need a staircase
    // up to this platform"), test-bench geometry for camera/
    // movement, and quick prototyping of stepped terrain.
    std::string womBase = argv[++i];
    int steps = 5;
    float stepHeight = 0.2f, stepDepth = 0.3f, width = 1.0f;
    try { steps = std::stoi(argv[++i]); }
    catch (...) {
        std::fprintf(stderr,
            "gen-mesh-stairs: <steps> must be an integer\n");
        return 1;
    }
    if (steps < 1 || steps > 256) {
        std::fprintf(stderr,
            "gen-mesh-stairs: steps %d out of range (1..256)\n", steps);
        return 1;
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { stepHeight = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { stepDepth = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { width = std::stof(argv[++i]); } catch (...) {}
    }
    if (stepHeight <= 0 || stepDepth <= 0 || width <= 0) {
        std::fprintf(stderr,
            "gen-mesh-stairs: dimensions must be positive\n");
        return 1;
    }
    if (womBase.size() >= 4 &&
        womBase.substr(womBase.size() - 4) == ".wom") {
        womBase = womBase.substr(0, womBase.size() - 4);
    }
    wowee::pipeline::WoweeModel wom;
    wom.name = std::filesystem::path(womBase).stem().string();
    wom.version = 3;
    auto addV = [&](float x, float y, float z,
                      float nx, float ny, float nz,
                      float u, float v) -> uint32_t {
        wowee::pipeline::WoweeModel::Vertex vtx;
        vtx.position = glm::vec3(x, y, z);
        vtx.normal = glm::vec3(nx, ny, nz);
        vtx.texCoord = glm::vec2(u, v);
        wom.vertices.push_back(vtx);
        return static_cast<uint32_t>(wom.vertices.size() - 1);
    };
    float halfW = width * 0.5f;
    // Each step is a box from y=0 to y=(k+1)*stepHeight,
    // depth-wise from x=k*stepDepth to x=(k+1)*stepDepth,
    // width-wise from z=-halfW to z=+halfW. Six faces per
    // step, four verts each = 24 verts / 12 tris per step.
    for (int k = 0; k < steps; ++k) {
        float x0 = k * stepDepth;
        float x1 = (k + 1) * stepDepth;
        float y0 = 0.0f;
        float y1 = (k + 1) * stepHeight;
        float z0 = -halfW;
        float z1 =  halfW;
        struct Face { float nx, ny, nz; float verts[4][3]; };
        Face faces[6] = {
            { 0,  1,  0, {{x0,y1,z0},{x1,y1,z0},{x1,y1,z1},{x0,y1,z1}}},  // top  +Y
            { 0, -1,  0, {{x0,y0,z0},{x0,y0,z1},{x1,y0,z1},{x1,y0,z0}}},  // bot  -Y
            {-1,  0,  0, {{x0,y0,z0},{x0,y1,z0},{x0,y1,z1},{x0,y0,z1}}},  // back -X
            { 1,  0,  0, {{x1,y0,z0},{x1,y0,z1},{x1,y1,z1},{x1,y1,z0}}},  // front+X (riser)
            { 0,  0, -1, {{x0,y0,z0},{x1,y0,z0},{x1,y1,z0},{x0,y1,z0}}},  // -Z
            { 0,  0,  1, {{x0,y0,z1},{x0,y1,z1},{x1,y1,z1},{x1,y0,z1}}},  // +Z
        };
        float uvs[4][2] = {{0,0},{1,0},{1,1},{0,1}};
        for (auto& f : faces) {
            uint32_t base = static_cast<uint32_t>(wom.vertices.size());
            for (int q = 0; q < 4; ++q) {
                addV(f.verts[q][0], f.verts[q][1], f.verts[q][2],
                      f.nx, f.ny, f.nz, uvs[q][0], uvs[q][1]);
            }
            wom.indices.push_back(base + 0);
            wom.indices.push_back(base + 1);
            wom.indices.push_back(base + 2);
            wom.indices.push_back(base + 0);
            wom.indices.push_back(base + 2);
            wom.indices.push_back(base + 3);
        }
    }
    wom.boundMin = glm::vec3(1e30f);
    wom.boundMax = glm::vec3(-1e30f);
    for (const auto& v : wom.vertices) {
        wom.boundMin = glm::min(wom.boundMin, v.position);
        wom.boundMax = glm::max(wom.boundMax, v.position);
    }
    wom.boundRadius = glm::length(wom.boundMax - wom.boundMin) * 0.5f;
    wowee::pipeline::WoweeModel::Batch b;
    b.indexStart = 0;
    b.indexCount = static_cast<uint32_t>(wom.indices.size());
    b.textureIndex = 0;
    b.blendMode = 0;
    b.flags = 0;
    wom.batches.push_back(b);
    wom.texturePaths.push_back("");
    std::filesystem::path womPath(womBase);
    std::filesystem::create_directories(womPath.parent_path());
    if (!wowee::pipeline::WoweeModelLoader::save(wom, womBase)) {
        std::fprintf(stderr,
            "gen-mesh-stairs: failed to save %s.wom\n", womBase.c_str());
        return 1;
    }
    std::printf("Wrote %s.wom\n", womBase.c_str());
    std::printf("  steps     : %d\n", steps);
    std::printf("  stepHt    : %.3f\n", stepHeight);
    std::printf("  stepDep   : %.3f\n", stepDepth);
    std::printf("  width     : %.3f\n", width);
    std::printf("  vertices  : %zu (%d per step × %d)\n",
                wom.vertices.size(), 24, steps);
    std::printf("  triangles : %zu\n", wom.indices.size() / 3);
    std::printf("  span      : %.3fL × %.3fH × %.3fW\n",
                steps * stepDepth, steps * stepHeight, width);
    return 0;
}

int handleGrid(int& i, int argc, char** argv) {
    // Flat plane subdivided into NxN cells. Useful for LOD
    // demos, deformable surfaces (later --displace passes),
    // testbench geometry that needs many triangles. Default
    // size is 1.0 (centered on origin). Hard cap at N=256
    // so a typo doesn't generate a mesh with 130k+ vertices.
    std::string womBase = argv[++i];
    int N = 0;
    try { N = std::stoi(argv[++i]); }
    catch (...) {
        std::fprintf(stderr,
            "gen-mesh-grid: <subdivisions> must be an integer\n");
        return 1;
    }
    if (N < 1 || N > 256) {
        std::fprintf(stderr,
            "gen-mesh-grid: subdivisions %d out of range (1..256)\n", N);
        return 1;
    }
    float size = 1.0f;
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { size = std::stof(argv[++i]); } catch (...) {}
    }
    if (size <= 0.0f) {
        std::fprintf(stderr,
            "gen-mesh-grid: size must be positive\n");
        return 1;
    }
    if (womBase.size() >= 4 &&
        womBase.substr(womBase.size() - 4) == ".wom") {
        womBase = womBase.substr(0, womBase.size() - 4);
    }
    wowee::pipeline::WoweeModel wom;
    wom.name = std::filesystem::path(womBase).stem().string();
    wom.version = 3;
    // (N+1)x(N+1) vertices on the XY plane centered on origin,
    // Z=0. Normals all point +Z; UVs are 0..1 across the grid.
    float halfSize = size * 0.5f;
    float cellSize = size / N;
    for (int j = 0; j <= N; ++j) {
        for (int k = 0; k <= N; ++k) {
            wowee::pipeline::WoweeModel::Vertex v;
            v.position = glm::vec3(-halfSize + k * cellSize,
                                    -halfSize + j * cellSize,
                                    0.0f);
            v.normal = glm::vec3(0, 0, 1);
            v.texCoord = glm::vec2(static_cast<float>(k) / N,
                                    static_cast<float>(j) / N);
            wom.vertices.push_back(v);
        }
    }
    int stride = N + 1;
    for (int j = 0; j < N; ++j) {
        for (int k = 0; k < N; ++k) {
            uint32_t a = j * stride + k;
            uint32_t b = a + 1;
            uint32_t c = a + stride;
            uint32_t d = c + 1;
            wom.indices.push_back(a);
            wom.indices.push_back(c);
            wom.indices.push_back(b);
            wom.indices.push_back(b);
            wom.indices.push_back(c);
            wom.indices.push_back(d);
        }
    }
    wom.boundMin = glm::vec3(-halfSize, -halfSize, 0);
    wom.boundMax = glm::vec3( halfSize,  halfSize, 0);
    wom.boundRadius = glm::length(wom.boundMax - wom.boundMin) * 0.5f;
    wowee::pipeline::WoweeModel::Batch b;
    b.indexStart = 0;
    b.indexCount = static_cast<uint32_t>(wom.indices.size());
    b.textureIndex = 0;
    b.blendMode = 0;
    b.flags = 0;
    wom.batches.push_back(b);
    wom.texturePaths.push_back("");
    std::filesystem::path womPath(womBase);
    std::filesystem::create_directories(womPath.parent_path());
    if (!wowee::pipeline::WoweeModelLoader::save(wom, womBase)) {
        std::fprintf(stderr,
            "gen-mesh-grid: failed to save %s.wom\n", womBase.c_str());
        return 1;
    }
    std::printf("Wrote %s.wom\n", womBase.c_str());
    std::printf("  subdivisions : %d (%dx%d cells)\n", N, N, N);
    std::printf("  size         : %.3f\n", size);
    std::printf("  vertices     : %zu = (N+1)²\n", wom.vertices.size());
    std::printf("  triangles    : %zu = 2N²\n", wom.indices.size() / 3);
    return 0;
}

int handleDisc(int& i, int argc, char** argv) {
    // Flat circular disc on XY centered at origin. Center
    // vertex + ring of <segments> verts, indexed as a fan.
    // Useful for magic circles, coin meshes, lily pads, top
    // caps for cylinders the user wants without making a
    // full cylinder.
    std::string womBase = argv[++i];
    float radius = 1.0f;
    int segments = 32;
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { radius = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { segments = std::stoi(argv[++i]); } catch (...) {}
    }
    if (radius <= 0.0f || segments < 3 || segments > 1024) {
        std::fprintf(stderr,
            "gen-mesh-disc: radius must be positive, segments 3..1024\n");
        return 1;
    }
    if (womBase.size() >= 4 &&
        womBase.substr(womBase.size() - 4) == ".wom") {
        womBase = womBase.substr(0, womBase.size() - 4);
    }
    wowee::pipeline::WoweeModel wom;
    wom.name = std::filesystem::path(womBase).stem().string();
    wom.version = 3;
    // Center vertex.
    {
        wowee::pipeline::WoweeModel::Vertex v;
        v.position = glm::vec3(0, 0, 0);
        v.normal = glm::vec3(0, 0, 1);
        v.texCoord = glm::vec2(0.5f, 0.5f);
        wom.vertices.push_back(v);
    }
    // Ring vertices (one extra at end so UV-seam isn't shared).
    for (int k = 0; k <= segments; ++k) {
        float t = static_cast<float>(k) / segments;
        float ang = t * 2.0f * 3.14159265358979f;
        float ca = std::cos(ang), sa = std::sin(ang);
        wowee::pipeline::WoweeModel::Vertex v;
        v.position = glm::vec3(radius * ca, radius * sa, 0);
        v.normal = glm::vec3(0, 0, 1);
        v.texCoord = glm::vec2(0.5f + 0.5f * ca, 0.5f + 0.5f * sa);
        wom.vertices.push_back(v);
    }
    // Fan indices.
    for (int k = 0; k < segments; ++k) {
        wom.indices.push_back(0);
        wom.indices.push_back(1 + k);
        wom.indices.push_back(2 + k);
    }
    wom.boundMin = glm::vec3(-radius, -radius, 0);
    wom.boundMax = glm::vec3( radius,  radius, 0);
    wom.boundRadius = radius;
    wowee::pipeline::WoweeModel::Batch b;
    b.indexStart = 0;
    b.indexCount = static_cast<uint32_t>(wom.indices.size());
    b.textureIndex = 0;
    b.blendMode = 0;
    b.flags = 0;
    wom.batches.push_back(b);
    wom.texturePaths.push_back("");
    std::filesystem::path womPath(womBase);
    std::filesystem::create_directories(womPath.parent_path());
    if (!wowee::pipeline::WoweeModelLoader::save(wom, womBase)) {
        std::fprintf(stderr,
            "gen-mesh-disc: failed to save %s.wom\n", womBase.c_str());
        return 1;
    }
    std::printf("Wrote %s.wom\n", womBase.c_str());
    std::printf("  radius    : %.3f\n", radius);
    std::printf("  segments  : %d\n", segments);
    std::printf("  vertices  : %zu (1 center + %d ring)\n",
                wom.vertices.size(), segments + 1);
    std::printf("  triangles : %zu\n", wom.indices.size() / 3);
    return 0;
}

int handleTube(int& i, int argc, char** argv) {
    // Hollow cylinder along Y axis. Outer + inner walls + top
    // and bottom annular caps. Useful for railings, fence
    // posts, pipes, hollow logs, ring towers — anywhere a
    // solid cylinder would feel wrong because you should be
    // able to see through the middle.
    std::string womBase = argv[++i];
    float outerR = 1.0f;
    float innerR = 0.7f;
    float height = 2.0f;
    int segments = 24;
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { outerR = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { innerR = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { height = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { segments = std::stoi(argv[++i]); } catch (...) {}
    }
    if (outerR <= 0 || innerR <= 0 || innerR >= outerR ||
        height <= 0 || segments < 3 || segments > 1024) {
        std::fprintf(stderr,
            "gen-mesh-tube: 0 < innerR < outerR, height > 0, segments 3..1024\n");
        return 1;
    }
    if (womBase.size() >= 4 &&
        womBase.substr(womBase.size() - 4) == ".wom") {
        womBase = womBase.substr(0, womBase.size() - 4);
    }
    wowee::pipeline::WoweeModel wom;
    wom.name = std::filesystem::path(womBase).stem().string();
    wom.version = 3;
    float h = height * 0.5f;
    auto addV = [&](float x, float y, float z,
                      float nx, float ny, float nz,
                      float u, float v) {
        wowee::pipeline::WoweeModel::Vertex vtx;
        vtx.position = glm::vec3(x, y, z);
        vtx.normal = glm::vec3(nx, ny, nz);
        vtx.texCoord = glm::vec2(u, v);
        wom.vertices.push_back(vtx);
        return static_cast<uint32_t>(wom.vertices.size() - 1);
    };
    // Outer wall: 2 rows × (segments+1) verts, normals point
    // radially outward.
    uint32_t outerStart = static_cast<uint32_t>(wom.vertices.size());
    for (int sg = 0; sg <= segments; ++sg) {
        float u = static_cast<float>(sg) / segments;
        float ang = u * 2.0f * 3.14159265358979f;
        float ca = std::cos(ang), sa = std::sin(ang);
        addV(outerR * ca, -h, outerR * sa, ca, 0, sa, u, 0);
        addV(outerR * ca,  h, outerR * sa, ca, 0, sa, u, 1);
    }
    for (int sg = 0; sg < segments; ++sg) {
        uint32_t a = outerStart + sg * 2;
        uint32_t b = a + 1, c = a + 2, d = a + 3;
        wom.indices.push_back(a);
        wom.indices.push_back(c);
        wom.indices.push_back(b);
        wom.indices.push_back(b);
        wom.indices.push_back(c);
        wom.indices.push_back(d);
    }
    // Inner wall: normals point radially inward, winding
    // reversed so the inside-facing surfaces face the viewer
    // when looking through the tube.
    uint32_t innerStart = static_cast<uint32_t>(wom.vertices.size());
    for (int sg = 0; sg <= segments; ++sg) {
        float u = static_cast<float>(sg) / segments;
        float ang = u * 2.0f * 3.14159265358979f;
        float ca = std::cos(ang), sa = std::sin(ang);
        addV(innerR * ca, -h, innerR * sa, -ca, 0, -sa, u, 0);
        addV(innerR * ca,  h, innerR * sa, -ca, 0, -sa, u, 1);
    }
    for (int sg = 0; sg < segments; ++sg) {
        uint32_t a = innerStart + sg * 2;
        uint32_t b = a + 1, c = a + 2, d = a + 3;
        wom.indices.push_back(a);
        wom.indices.push_back(b);
        wom.indices.push_back(c);
        wom.indices.push_back(b);
        wom.indices.push_back(d);
        wom.indices.push_back(c);
    }
    // Top annular cap: ring at +Y. Inner + outer ring of verts,
    // quads stitched between them, normal +Y.
    uint32_t topInner = static_cast<uint32_t>(wom.vertices.size());
    for (int sg = 0; sg <= segments; ++sg) {
        float u = static_cast<float>(sg) / segments;
        float ang = u * 2.0f * 3.14159265358979f;
        float ca = std::cos(ang), sa = std::sin(ang);
        addV(innerR * ca, h, innerR * sa, 0, 1, 0,
               0.5f + 0.5f * (innerR / outerR) * ca,
               0.5f + 0.5f * (innerR / outerR) * sa);
    }
    uint32_t topOuter = static_cast<uint32_t>(wom.vertices.size());
    for (int sg = 0; sg <= segments; ++sg) {
        float u = static_cast<float>(sg) / segments;
        float ang = u * 2.0f * 3.14159265358979f;
        float ca = std::cos(ang), sa = std::sin(ang);
        addV(outerR * ca, h, outerR * sa, 0, 1, 0,
               0.5f + 0.5f * ca, 0.5f + 0.5f * sa);
    }
    for (int sg = 0; sg < segments; ++sg) {
        uint32_t a = topInner + sg;
        uint32_t b = topInner + sg + 1;
        uint32_t c = topOuter + sg;
        uint32_t d = topOuter + sg + 1;
        wom.indices.push_back(a);
        wom.indices.push_back(c);
        wom.indices.push_back(b);
        wom.indices.push_back(b);
        wom.indices.push_back(c);
        wom.indices.push_back(d);
    }
    // Bottom annular cap, normal -Y, winding reversed.
    uint32_t botInner = static_cast<uint32_t>(wom.vertices.size());
    for (int sg = 0; sg <= segments; ++sg) {
        float u = static_cast<float>(sg) / segments;
        float ang = u * 2.0f * 3.14159265358979f;
        float ca = std::cos(ang), sa = std::sin(ang);
        addV(innerR * ca, -h, innerR * sa, 0, -1, 0,
               0.5f + 0.5f * (innerR / outerR) * ca,
               0.5f - 0.5f * (innerR / outerR) * sa);
    }
    uint32_t botOuter = static_cast<uint32_t>(wom.vertices.size());
    for (int sg = 0; sg <= segments; ++sg) {
        float u = static_cast<float>(sg) / segments;
        float ang = u * 2.0f * 3.14159265358979f;
        float ca = std::cos(ang), sa = std::sin(ang);
        addV(outerR * ca, -h, outerR * sa, 0, -1, 0,
               0.5f + 0.5f * ca, 0.5f - 0.5f * sa);
    }
    for (int sg = 0; sg < segments; ++sg) {
        uint32_t a = botInner + sg;
        uint32_t b = botInner + sg + 1;
        uint32_t c = botOuter + sg;
        uint32_t d = botOuter + sg + 1;
        wom.indices.push_back(a);
        wom.indices.push_back(b);
        wom.indices.push_back(c);
        wom.indices.push_back(b);
        wom.indices.push_back(d);
        wom.indices.push_back(c);
    }
    wom.boundMin = glm::vec3(-outerR, -h, -outerR);
    wom.boundMax = glm::vec3( outerR,  h,  outerR);
    wom.boundRadius = glm::length(wom.boundMax - wom.boundMin) * 0.5f;
    wowee::pipeline::WoweeModel::Batch b;
    b.indexStart = 0;
    b.indexCount = static_cast<uint32_t>(wom.indices.size());
    b.textureIndex = 0;
    b.blendMode = 0;
    b.flags = 0;
    wom.batches.push_back(b);
    wom.texturePaths.push_back("");
    std::filesystem::path womPath(womBase);
    std::filesystem::create_directories(womPath.parent_path());
    if (!wowee::pipeline::WoweeModelLoader::save(wom, womBase)) {
        std::fprintf(stderr,
            "gen-mesh-tube: failed to save %s.wom\n", womBase.c_str());
        return 1;
    }
    std::printf("Wrote %s.wom\n", womBase.c_str());
    std::printf("  outer R   : %.3f\n", outerR);
    std::printf("  inner R   : %.3f\n", innerR);
    std::printf("  height    : %.3f\n", height);
    std::printf("  segments  : %d\n", segments);
    std::printf("  vertices  : %zu\n", wom.vertices.size());
    std::printf("  triangles : %zu\n", wom.indices.size() / 3);
    return 0;
}

int handleCapsule(int& i, int argc, char** argv) {
    // Capsule along the Y axis: cylindrical body of length
    // cylHeight bookended by two hemispheres of radius. Total
    // height is cylHeight + 2*radius. Useful for character
    // collision shells, pill-shaped buttons, hot-dog props,
    // and physics-friendly placeholders.
    std::string womBase = argv[++i];
    float radius = 0.5f;
    float cylHeight = 1.0f;
    int segments = 16;
    int stacks = 8;  // per hemisphere
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { radius = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { cylHeight = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { segments = std::stoi(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { stacks = std::stoi(argv[++i]); } catch (...) {}
    }
    if (radius <= 0 || cylHeight < 0 ||
        segments < 3 || segments > 1024 ||
        stacks < 1 || stacks > 256) {
        std::fprintf(stderr,
            "gen-mesh-capsule: radius > 0, cylHeight >= 0, segments 3..1024, stacks 1..256\n");
        return 1;
    }
    if (womBase.size() >= 4 &&
        womBase.substr(womBase.size() - 4) == ".wom") {
        womBase = womBase.substr(0, womBase.size() - 4);
    }
    wowee::pipeline::WoweeModel wom;
    wom.name = std::filesystem::path(womBase).stem().string();
    wom.version = 3;
    float halfBody = cylHeight * 0.5f;
    float totalH = cylHeight + 2.0f * radius;
    auto addV = [&](float x, float y, float z,
                      float nx, float ny, float nz,
                      float u, float v) {
        wowee::pipeline::WoweeModel::Vertex vtx;
        vtx.position = glm::vec3(x, y, z);
        vtx.normal = glm::vec3(nx, ny, nz);
        vtx.texCoord = glm::vec2(u, v);
        wom.vertices.push_back(vtx);
        return static_cast<uint32_t>(wom.vertices.size() - 1);
    };
    // Top hemisphere: stacks rings from north pole down to
    // body top. Vertex layout per ring: (segments+1) verts.
    const float pi = 3.14159265358979f;
    int totalVPerRing = segments + 1;
    // Top hemisphere rings: stacks+1 rings (ring 0 is the
    // pole). v texcoord goes 0..0.25 across the cap.
    for (int st = 0; st <= stacks; ++st) {
        float t = static_cast<float>(st) / stacks;
        float phi = t * (pi * 0.5f);  // 0 at pole, π/2 at body
        float sphi = std::sin(phi), cphi = std::cos(phi);
        float ringR = radius * sphi;
        float ringY = halfBody + radius * cphi;
        for (int sg = 0; sg <= segments; ++sg) {
            float u = static_cast<float>(sg) / segments;
            float ang = u * 2.0f * pi;
            float ca = std::cos(ang), sa = std::sin(ang);
            addV(ringR * ca, ringY, ringR * sa,
                  sphi * ca, cphi, sphi * sa,
                  u, t * 0.25f);
        }
    }
    // Body: 2 rings (top and bottom of cylinder), normal
    // radial (no Y component). UV goes 0.25..0.75.
    int bodyTopRingStart = static_cast<int>(wom.vertices.size());
    for (int sg = 0; sg <= segments; ++sg) {
        float u = static_cast<float>(sg) / segments;
        float ang = u * 2.0f * pi;
        float ca = std::cos(ang), sa = std::sin(ang);
        addV(radius * ca, halfBody, radius * sa, ca, 0, sa, u, 0.25f);
    }
    int bodyBotRingStart = static_cast<int>(wom.vertices.size());
    for (int sg = 0; sg <= segments; ++sg) {
        float u = static_cast<float>(sg) / segments;
        float ang = u * 2.0f * pi;
        float ca = std::cos(ang), sa = std::sin(ang);
        addV(radius * ca, -halfBody, radius * sa, ca, 0, sa, u, 0.75f);
    }
    // Bottom hemisphere: mirror of top.
    int botHemiStart = static_cast<int>(wom.vertices.size());
    for (int st = 0; st <= stacks; ++st) {
        float t = static_cast<float>(st) / stacks;
        float phi = t * (pi * 0.5f);
        float sphi = std::sin(phi), cphi = std::cos(phi);
        float ringR = radius * cphi;
        float ringY = -halfBody - radius * sphi;
        for (int sg = 0; sg <= segments; ++sg) {
            float u = static_cast<float>(sg) / segments;
            float ang = u * 2.0f * pi;
            float ca = std::cos(ang), sa = std::sin(ang);
            addV(ringR * ca, ringY, ringR * sa,
                  cphi * ca, -sphi, cphi * sa,
                  u, 0.75f + t * 0.25f);
        }
    }
    // Index the rings: top hemi (stacks rings → stacks-1
    // bands), body (1 band), bottom hemi (stacks bands).
    auto stitch = [&](int topRingStart, int botRingStart) {
        for (int sg = 0; sg < segments; ++sg) {
            uint32_t a = topRingStart + sg;
            uint32_t b = a + 1;
            uint32_t c = botRingStart + sg;
            uint32_t d = c + 1;
            wom.indices.push_back(a);
            wom.indices.push_back(c);
            wom.indices.push_back(b);
            wom.indices.push_back(b);
            wom.indices.push_back(c);
            wom.indices.push_back(d);
        }
    };
    // Top hemisphere bands.
    for (int st = 0; st < stacks; ++st) {
        stitch(st * totalVPerRing, (st + 1) * totalVPerRing);
    }
    // Body band: between bodyTopRingStart and bodyBotRingStart.
    stitch(bodyTopRingStart, bodyBotRingStart);
    // Bottom hemisphere bands.
    for (int st = 0; st < stacks; ++st) {
        stitch(botHemiStart + st * totalVPerRing,
                botHemiStart + (st + 1) * totalVPerRing);
    }
    wom.boundMin = glm::vec3(-radius, -totalH * 0.5f, -radius);
    wom.boundMax = glm::vec3( radius,  totalH * 0.5f,  radius);
    wom.boundRadius = glm::length(wom.boundMax - wom.boundMin) * 0.5f;
    wowee::pipeline::WoweeModel::Batch b;
    b.indexStart = 0;
    b.indexCount = static_cast<uint32_t>(wom.indices.size());
    b.textureIndex = 0;
    b.blendMode = 0;
    b.flags = 0;
    wom.batches.push_back(b);
    wom.texturePaths.push_back("");
    std::filesystem::path womPath(womBase);
    std::filesystem::create_directories(womPath.parent_path());
    if (!wowee::pipeline::WoweeModelLoader::save(wom, womBase)) {
        std::fprintf(stderr,
            "gen-mesh-capsule: failed to save %s.wom\n", womBase.c_str());
        return 1;
    }
    std::printf("Wrote %s.wom\n", womBase.c_str());
    std::printf("  radius     : %.3f\n", radius);
    std::printf("  cylHeight  : %.3f\n", cylHeight);
    std::printf("  total H    : %.3f\n", totalH);
    std::printf("  segments   : %d\n", segments);
    std::printf("  stacks     : %d (per hemisphere)\n", stacks);
    std::printf("  vertices   : %zu\n", wom.vertices.size());
    std::printf("  triangles  : %zu\n", wom.indices.size() / 3);
    return 0;
}

int handleArch(int& i, int argc, char** argv) {
    // Doorway/portal arch: two rectangular columns connected
    // by a semicircular top band. Total width = openingWidth +
    // 2*thickness; total height = openingHeight + thickness +
    // archRadius (where archRadius = openingWidth/2). Depth
    // is the Y-axis thickness (extruded slab).
    //
    // Two box columns + curved arch band on top. Useful for
    // doorways, portal frames, gates. Aligned so the inside
    // of the opening is centered on the Y axis.
    std::string womBase = argv[++i];
    float openingW = 1.0f, openingH = 1.5f;
    float thickness = 0.2f;  // column thickness (X)
    float depth = 0.3f;       // Y extrusion
    int segments = 12;        // arch curve segments
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { openingW = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { openingH = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { thickness = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { depth = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { segments = std::stoi(argv[++i]); } catch (...) {}
    }
    if (openingW <= 0 || openingH <= 0 ||
        thickness <= 0 || depth <= 0 ||
        segments < 2 || segments > 256) {
        std::fprintf(stderr,
            "gen-mesh-arch: dimensions must be positive, segments 2..256\n");
        return 1;
    }
    if (womBase.size() >= 4 &&
        womBase.substr(womBase.size() - 4) == ".wom") {
        womBase = womBase.substr(0, womBase.size() - 4);
    }
    wowee::pipeline::WoweeModel wom;
    wom.name = std::filesystem::path(womBase).stem().string();
    wom.version = 3;
    // Helper to push a vertex.
    auto addV = [&](float x, float y, float z,
                      float nx, float ny, float nz,
                      float u, float v) -> uint32_t {
        wowee::pipeline::WoweeModel::Vertex vtx;
        vtx.position = glm::vec3(x, y, z);
        vtx.normal = glm::vec3(nx, ny, nz);
        vtx.texCoord = glm::vec2(u, v);
        wom.vertices.push_back(vtx);
        return static_cast<uint32_t>(wom.vertices.size() - 1);
    };
    // Helper to emit an axis-aligned box from min to max.
    auto addBox = [&](glm::vec3 lo, glm::vec3 hi) {
        struct Face { float nx, ny, nz; float verts[4][3]; };
        Face faces[6] = {
            { 0,  0,  1, {{lo.x,lo.y,hi.z},{hi.x,lo.y,hi.z},{hi.x,hi.y,hi.z},{lo.x,hi.y,hi.z}}},
            { 0,  0, -1, {{hi.x,lo.y,lo.z},{lo.x,lo.y,lo.z},{lo.x,hi.y,lo.z},{hi.x,hi.y,lo.z}}},
            { 1,  0,  0, {{hi.x,lo.y,hi.z},{hi.x,lo.y,lo.z},{hi.x,hi.y,lo.z},{hi.x,hi.y,hi.z}}},
            {-1,  0,  0, {{lo.x,lo.y,lo.z},{lo.x,lo.y,hi.z},{lo.x,hi.y,hi.z},{lo.x,hi.y,lo.z}}},
            { 0,  1,  0, {{lo.x,hi.y,hi.z},{hi.x,hi.y,hi.z},{hi.x,hi.y,lo.z},{lo.x,hi.y,lo.z}}},
            { 0, -1,  0, {{lo.x,lo.y,lo.z},{hi.x,lo.y,lo.z},{hi.x,lo.y,hi.z},{lo.x,lo.y,hi.z}}},
        };
        float uvs[4][2] = {{0,0},{1,0},{1,1},{0,1}};
        for (auto& f : faces) {
            uint32_t base = static_cast<uint32_t>(wom.vertices.size());
            for (int k = 0; k < 4; ++k) {
                addV(f.verts[k][0], f.verts[k][1], f.verts[k][2],
                      f.nx, f.ny, f.nz, uvs[k][0], uvs[k][1]);
            }
            wom.indices.push_back(base + 0);
            wom.indices.push_back(base + 1);
            wom.indices.push_back(base + 2);
            wom.indices.push_back(base + 0);
            wom.indices.push_back(base + 2);
            wom.indices.push_back(base + 3);
        }
    };
    float halfOW = openingW * 0.5f;
    float halfD = depth * 0.5f;
    // Left column.
    addBox(glm::vec3(-halfOW - thickness, -halfD, 0),
            glm::vec3(-halfOW, halfD, openingH));
    // Right column.
    addBox(glm::vec3(halfOW, -halfD, 0),
            glm::vec3(halfOW + thickness, halfD, openingH));
    // Arch top band: curve from (-halfOW, openingH) through
    // (0, openingH+halfOW) to (halfOW, openingH). Radius =
    // halfOW. Outer surface follows the curve, inner surface
    // is the underside. Built from <segments> bands of 4
    // verts each (front + back faces handled per band).
    float archCenterZ = openingH;
    float archR = halfOW;
    float pi = 3.14159265358979f;
    for (int sg = 0; sg < segments; ++sg) {
        float t0 = static_cast<float>(sg) / segments;
        float t1 = static_cast<float>(sg + 1) / segments;
        float a0 = pi - t0 * pi;  // start at 180°, sweep to 0°
        float a1 = pi - t1 * pi;
        float c0 = std::cos(a0), s0 = std::sin(a0);
        float c1 = std::cos(a1), s1 = std::sin(a1);
        // Outer ring point at angle a.
        glm::vec3 outer0(archR * c0, 0, archCenterZ + archR * s0);
        glm::vec3 outer1(archR * c1, 0, archCenterZ + archR * s1);
        // Inner ring (offset down to be a thin band — we're
        // making just a bridge across the top, no thickness
        // for now to keep vertex count tractable). The arch
        // band is a flat strip from the outer curve down to
        // the column tops at the SAME XZ — use the column
        // tops at the band ends. For simplicity, treat the
        // band as a thin shell along the curve.
        glm::vec3 outer0b = outer0 + glm::vec3(0, depth, 0);
        glm::vec3 outer1b = outer1 + glm::vec3(0, depth, 0);
        // Top face of band (pointing radially outward from
        // arch center).
        glm::vec3 n((c0 + c1) * 0.5f, 0, (s0 + s1) * 0.5f);
        n = glm::normalize(n);
        uint32_t base = static_cast<uint32_t>(wom.vertices.size());
        addV(outer0.x, outer0.y - halfD, outer0.z, n.x, 0, n.z, 0, 0);
        addV(outer1.x, outer1.y - halfD, outer1.z, n.x, 0, n.z, 1, 0);
        addV(outer1.x, outer1.y + halfD, outer1.z, n.x, 0, n.z, 1, 1);
        addV(outer0.x, outer0.y + halfD, outer0.z, n.x, 0, n.z, 0, 1);
        wom.indices.push_back(base + 0);
        wom.indices.push_back(base + 1);
        wom.indices.push_back(base + 2);
        wom.indices.push_back(base + 0);
        wom.indices.push_back(base + 2);
        wom.indices.push_back(base + 3);
    }
    wom.boundMin = glm::vec3(1e30f);
    wom.boundMax = glm::vec3(-1e30f);
    for (const auto& v : wom.vertices) {
        wom.boundMin = glm::min(wom.boundMin, v.position);
        wom.boundMax = glm::max(wom.boundMax, v.position);
    }
    wom.boundRadius = glm::length(wom.boundMax - wom.boundMin) * 0.5f;
    wowee::pipeline::WoweeModel::Batch b;
    b.indexStart = 0;
    b.indexCount = static_cast<uint32_t>(wom.indices.size());
    b.textureIndex = 0;
    b.blendMode = 0;
    b.flags = 0;
    wom.batches.push_back(b);
    wom.texturePaths.push_back("");
    std::filesystem::path womPath(womBase);
    std::filesystem::create_directories(womPath.parent_path());
    if (!wowee::pipeline::WoweeModelLoader::save(wom, womBase)) {
        std::fprintf(stderr,
            "gen-mesh-arch: failed to save %s.wom\n", womBase.c_str());
        return 1;
    }
    std::printf("Wrote %s.wom\n", womBase.c_str());
    std::printf("  opening    : %.3f W × %.3f H\n", openingW, openingH);
    std::printf("  thickness  : %.3f (column), depth %.3f (Y)\n", thickness, depth);
    std::printf("  segments   : %d (arch curve)\n", segments);
    std::printf("  vertices   : %zu\n", wom.vertices.size());
    std::printf("  triangles  : %zu\n", wom.indices.size() / 3);
    std::printf("  bounds     : (%.2f, %.2f, %.2f) - (%.2f, %.2f, %.2f)\n",
                wom.boundMin.x, wom.boundMin.y, wom.boundMin.z,
                wom.boundMax.x, wom.boundMax.y, wom.boundMax.z);
    return 0;
}

int handlePyramid(int& i, int argc, char** argv) {
    // N-sided polygonal pyramid with apex at +Y. 4 sides
    // gives a square pyramid; 3 gives a tetrahedron-like
    // shape; 8+ approaches a cone.
    //
    // Different from --gen-mesh cone: cone has smooth
    // round sides with per-vertex radial-ish normals;
    // pyramid has flat per-face normals on N triangular
    // sides + a flat polygonal base.
    std::string womBase = argv[++i];
    int sides = 4;
    float baseR = 1.0f;
    float height = 1.0f;
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { sides = std::stoi(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { baseR = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { height = std::stof(argv[++i]); } catch (...) {}
    }
    if (sides < 3 || sides > 256 || baseR <= 0 || height <= 0) {
        std::fprintf(stderr,
            "gen-mesh-pyramid: sides 3..256, baseR > 0, height > 0\n");
        return 1;
    }
    if (womBase.size() >= 4 &&
        womBase.substr(womBase.size() - 4) == ".wom") {
        womBase = womBase.substr(0, womBase.size() - 4);
    }
    wowee::pipeline::WoweeModel wom;
    wom.name = std::filesystem::path(womBase).stem().string();
    wom.version = 3;
    const float pi = 3.14159265358979f;
    auto addV = [&](glm::vec3 p, glm::vec3 n, glm::vec2 uv) -> uint32_t {
        wowee::pipeline::WoweeModel::Vertex vtx;
        vtx.position = p;
        vtx.normal = n;
        vtx.texCoord = uv;
        wom.vertices.push_back(vtx);
        return static_cast<uint32_t>(wom.vertices.size() - 1);
    };
    // Build base ring vertices (one per side).
    std::vector<glm::vec3> basePts;
    for (int k = 0; k < sides; ++k) {
        float a = static_cast<float>(k) / sides * 2.0f * pi;
        basePts.push_back(glm::vec3(baseR * std::cos(a), 0,
                                      baseR * std::sin(a)));
    }
    glm::vec3 apex(0, height, 0);
    // Side faces: per-face flat normals (cross of two edges).
    for (int k = 0; k < sides; ++k) {
        glm::vec3 a = basePts[k];
        glm::vec3 b = basePts[(k + 1) % sides];
        glm::vec3 e1 = b - a;
        glm::vec3 e2 = apex - a;
        glm::vec3 n = glm::normalize(glm::cross(e1, e2));
        float u0 = static_cast<float>(k) / sides;
        float u1 = static_cast<float>(k + 1) / sides;
        uint32_t i0 = addV(a, n, glm::vec2(u0, 1));
        uint32_t i1 = addV(b, n, glm::vec2(u1, 1));
        uint32_t i2 = addV(apex, n, glm::vec2(0.5f * (u0 + u1), 0));
        wom.indices.push_back(i0);
        wom.indices.push_back(i1);
        wom.indices.push_back(i2);
    }
    // Base: fan from a center vertex (normal -Y).
    uint32_t baseCenter = addV(glm::vec3(0, 0, 0),
                                 glm::vec3(0, -1, 0),
                                 glm::vec2(0.5f, 0.5f));
    uint32_t baseRingStart = static_cast<uint32_t>(wom.vertices.size());
    for (int k = 0; k < sides; ++k) {
        float a = static_cast<float>(k) / sides * 2.0f * pi;
        addV(basePts[k], glm::vec3(0, -1, 0),
               glm::vec2(0.5f + 0.5f * std::cos(a),
                          0.5f - 0.5f * std::sin(a)));
    }
    for (int k = 0; k < sides; ++k) {
        wom.indices.push_back(baseCenter);
        wom.indices.push_back(baseRingStart + (k + 1) % sides);
        wom.indices.push_back(baseRingStart + k);
    }
    wom.boundMin = glm::vec3(-baseR, 0, -baseR);
    wom.boundMax = glm::vec3( baseR, height, baseR);
    wom.boundRadius = glm::length(wom.boundMax - wom.boundMin) * 0.5f;
    wowee::pipeline::WoweeModel::Batch b;
    b.indexStart = 0;
    b.indexCount = static_cast<uint32_t>(wom.indices.size());
    b.textureIndex = 0;
    b.blendMode = 0;
    b.flags = 0;
    wom.batches.push_back(b);
    wom.texturePaths.push_back("");
    std::filesystem::path womPath(womBase);
    std::filesystem::create_directories(womPath.parent_path());
    if (!wowee::pipeline::WoweeModelLoader::save(wom, womBase)) {
        std::fprintf(stderr,
            "gen-mesh-pyramid: failed to save %s.wom\n", womBase.c_str());
        return 1;
    }
    std::printf("Wrote %s.wom\n", womBase.c_str());
    std::printf("  sides     : %d\n", sides);
    std::printf("  base R    : %.3f\n", baseR);
    std::printf("  height    : %.3f\n", height);
    std::printf("  vertices  : %zu (%d side tris × 3 + 1 base center + %d base ring)\n",
                wom.vertices.size(), sides, sides);
    std::printf("  triangles : %zu (%d sides + %d base)\n",
                wom.indices.size() / 3, sides, sides);
    return 0;
}

int handleFence(int& i, int argc, char** argv) {
    // Repeating fence: N square posts along +X spaced
    // <postSpacing> apart, with two horizontal rails (top
    // and bottom) connecting consecutive posts. Posts span
    // from Y=0 up to Y=postHeight; each post is a small box
    // of width = railThick × 2.
    //
    // Useful for fences around plots, pen boundaries,
    // walkway dividers, garden beds.
    std::string womBase = argv[++i];
    int posts = 5;
    float spacing = 1.0f;
    float postH = 1.0f;
    float rt = 0.05f;  // rail/post thickness
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { posts = std::stoi(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { spacing = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { postH = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { rt = std::stof(argv[++i]); } catch (...) {}
    }
    if (posts < 2 || posts > 256 ||
        spacing <= 0 || postH <= 0 || rt <= 0) {
        std::fprintf(stderr,
            "gen-mesh-fence: posts 2..256, spacing/height/thick > 0\n");
        return 1;
    }
    if (womBase.size() >= 4 &&
        womBase.substr(womBase.size() - 4) == ".wom") {
        womBase = womBase.substr(0, womBase.size() - 4);
    }
    wowee::pipeline::WoweeModel wom;
    wom.name = std::filesystem::path(womBase).stem().string();
    wom.version = 3;
    auto addV = [&](glm::vec3 p, glm::vec3 n, glm::vec2 uv) -> uint32_t {
        wowee::pipeline::WoweeModel::Vertex vtx;
        vtx.position = p;
        vtx.normal = n;
        vtx.texCoord = uv;
        wom.vertices.push_back(vtx);
        return static_cast<uint32_t>(wom.vertices.size() - 1);
    };
    auto addBox = [&](glm::vec3 lo, glm::vec3 hi) {
        struct Face { float nx, ny, nz; float verts[4][3]; };
        Face faces[6] = {
            { 0,  1,  0, {{lo.x,hi.y,hi.z},{hi.x,hi.y,hi.z},{hi.x,hi.y,lo.z},{lo.x,hi.y,lo.z}}},
            { 0, -1,  0, {{lo.x,lo.y,lo.z},{hi.x,lo.y,lo.z},{hi.x,lo.y,hi.z},{lo.x,lo.y,hi.z}}},
            { 0,  0,  1, {{lo.x,lo.y,hi.z},{hi.x,lo.y,hi.z},{hi.x,hi.y,hi.z},{lo.x,hi.y,hi.z}}},
            { 0,  0, -1, {{hi.x,lo.y,lo.z},{lo.x,lo.y,lo.z},{lo.x,hi.y,lo.z},{hi.x,hi.y,lo.z}}},
            { 1,  0,  0, {{hi.x,lo.y,hi.z},{hi.x,lo.y,lo.z},{hi.x,hi.y,lo.z},{hi.x,hi.y,hi.z}}},
            {-1,  0,  0, {{lo.x,lo.y,lo.z},{lo.x,lo.y,hi.z},{lo.x,hi.y,hi.z},{lo.x,hi.y,lo.z}}},
        };
        float uvs[4][2] = {{0,0},{1,0},{1,1},{0,1}};
        for (auto& f : faces) {
            uint32_t base = static_cast<uint32_t>(wom.vertices.size());
            for (int k = 0; k < 4; ++k) {
                addV(glm::vec3(f.verts[k][0], f.verts[k][1], f.verts[k][2]),
                      glm::vec3(f.nx, f.ny, f.nz),
                      glm::vec2(uvs[k][0], uvs[k][1]));
            }
            wom.indices.push_back(base + 0);
            wom.indices.push_back(base + 1);
            wom.indices.push_back(base + 2);
            wom.indices.push_back(base + 0);
            wom.indices.push_back(base + 2);
            wom.indices.push_back(base + 3);
        }
    };
    float postHalfW = rt;
    // Posts along +X starting at X=0.
    for (int k = 0; k < posts; ++k) {
        float cx = k * spacing;
        addBox(glm::vec3(cx - postHalfW, -postHalfW, 0),
                glm::vec3(cx + postHalfW,  postHalfW, postH));
    }
    // Rails between consecutive posts. Two rails per gap:
    // top (~80% up) and bottom (~30% up).
    float topRailZ = postH * 0.8f;
    float botRailZ = postH * 0.3f;
    float railHalfH = rt * 0.5f;  // rail is thinner than posts
    for (int k = 0; k + 1 < posts; ++k) {
        float xL = k * spacing + postHalfW;
        float xR = (k + 1) * spacing - postHalfW;
        if (xR <= xL) continue;  // posts touching
        addBox(glm::vec3(xL, -railHalfH, topRailZ - railHalfH),
                glm::vec3(xR,  railHalfH, topRailZ + railHalfH));
        addBox(glm::vec3(xL, -railHalfH, botRailZ - railHalfH),
                glm::vec3(xR,  railHalfH, botRailZ + railHalfH));
    }
    // Bounds.
    wom.boundMin = glm::vec3(-postHalfW, -postHalfW, 0);
    wom.boundMax = glm::vec3((posts - 1) * spacing + postHalfW,
                               postHalfW, postH);
    wom.boundRadius = glm::length(wom.boundMax - wom.boundMin) * 0.5f;
    wowee::pipeline::WoweeModel::Batch b;
    b.indexStart = 0;
    b.indexCount = static_cast<uint32_t>(wom.indices.size());
    b.textureIndex = 0;
    b.blendMode = 0;
    b.flags = 0;
    wom.batches.push_back(b);
    wom.texturePaths.push_back("");
    std::filesystem::path womPath(womBase);
    std::filesystem::create_directories(womPath.parent_path());
    if (!wowee::pipeline::WoweeModelLoader::save(wom, womBase)) {
        std::fprintf(stderr,
            "gen-mesh-fence: failed to save %s.wom\n", womBase.c_str());
        return 1;
    }
    std::printf("Wrote %s.wom\n", womBase.c_str());
    std::printf("  posts     : %d\n", posts);
    std::printf("  spacing   : %.3f\n", spacing);
    std::printf("  height    : %.3f\n", postH);
    std::printf("  thickness : %.3f\n", rt);
    std::printf("  span X    : %.3f\n", (posts - 1) * spacing);
    std::printf("  vertices  : %zu\n", wom.vertices.size());
    std::printf("  triangles : %zu\n", wom.indices.size() / 3);
    return 0;
}

int handleTree(int& i, int argc, char** argv) {
    // Procedural tree: cylinder trunk + UV-sphere foliage.
    // Trunk goes from Y=0 up to Y=trunkHeight; foliage sphere
    // centered at trunk-top + foliageRadius/2 so the trunk
    // pokes up into the bottom of the canopy.
    //
    // Useful for ambient zone decoration, distant tree
    // placeholders, magic-grove props. The 15th procedural
    // primitive — pairs naturally with --add-texture-to-mesh
    // for trunk-bark and leaf textures (or just one texture
    // since this is a single-batch mesh).
    std::string womBase = argv[++i];
    float trunkR = 0.1f;
    float trunkH = 2.0f;
    float foliR = 0.7f;
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { trunkR = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { trunkH = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { foliR = std::stof(argv[++i]); } catch (...) {}
    }
    if (trunkR <= 0 || trunkH <= 0 || foliR <= 0) {
        std::fprintf(stderr,
            "gen-mesh-tree: trunkR / trunkH / foliR must be positive\n");
        return 1;
    }
    if (womBase.size() >= 4 &&
        womBase.substr(womBase.size() - 4) == ".wom") {
        womBase = womBase.substr(0, womBase.size() - 4);
    }
    wowee::pipeline::WoweeModel wom;
    wom.name = std::filesystem::path(womBase).stem().string();
    wom.version = 3;
    const float pi = 3.14159265358979f;
    auto addV = [&](glm::vec3 p, glm::vec3 n, glm::vec2 uv) -> uint32_t {
        wowee::pipeline::WoweeModel::Vertex vtx;
        vtx.position = p;
        vtx.normal = n;
        vtx.texCoord = uv;
        wom.vertices.push_back(vtx);
        return static_cast<uint32_t>(wom.vertices.size() - 1);
    };
    // Trunk cylinder: 12 segments, side ring + top + bottom.
    const int trunkSegs = 12;
    uint32_t trunkSideStart = static_cast<uint32_t>(wom.vertices.size());
    for (int sg = 0; sg <= trunkSegs; ++sg) {
        float u = static_cast<float>(sg) / trunkSegs;
        float ang = u * 2.0f * pi;
        float ca = std::cos(ang), sa = std::sin(ang);
        addV(glm::vec3(trunkR * ca, 0, trunkR * sa),
               glm::vec3(ca, 0, sa),
               glm::vec2(u, 0));
        addV(glm::vec3(trunkR * ca, trunkH, trunkR * sa),
               glm::vec3(ca, 0, sa),
               glm::vec2(u, 1));
    }
    for (int sg = 0; sg < trunkSegs; ++sg) {
        uint32_t a = trunkSideStart + sg * 2;
        uint32_t b = a + 1, c = a + 2, d = a + 3;
        wom.indices.push_back(a);
        wom.indices.push_back(c);
        wom.indices.push_back(b);
        wom.indices.push_back(b);
        wom.indices.push_back(c);
        wom.indices.push_back(d);
    }
    // Foliage UV sphere: 12 segments × 8 stacks. Center at
    // (0, trunkH + foliR * 0.7, 0) so the trunk pokes into
    // the bottom of the canopy.
    const int fSegs = 12;
    const int fStacks = 8;
    float foliCY = trunkH + foliR * 0.7f;
    uint32_t foliStart = static_cast<uint32_t>(wom.vertices.size());
    for (int st = 0; st <= fStacks; ++st) {
        float v = static_cast<float>(st) / fStacks;
        float phi = v * pi;
        float sphi = std::sin(phi), cphi = std::cos(phi);
        for (int sg = 0; sg <= fSegs; ++sg) {
            float u = static_cast<float>(sg) / fSegs;
            float theta = u * 2.0f * pi;
            float ctheta = std::cos(theta), stheta = std::sin(theta);
            float nx = sphi * ctheta;
            float ny = cphi;
            float nz = sphi * stheta;
            addV(glm::vec3(foliR * nx, foliCY + foliR * ny, foliR * nz),
                   glm::vec3(nx, ny, nz),
                   glm::vec2(u, v));
        }
    }
    int fStride = fSegs + 1;
    for (int st = 0; st < fStacks; ++st) {
        for (int sg = 0; sg < fSegs; ++sg) {
            uint32_t a = foliStart + st * fStride + sg;
            uint32_t b = a + 1;
            uint32_t c = a + fStride;
            uint32_t d = c + 1;
            wom.indices.push_back(a);
            wom.indices.push_back(c);
            wom.indices.push_back(b);
            wom.indices.push_back(b);
            wom.indices.push_back(c);
            wom.indices.push_back(d);
        }
    }
    wom.boundMin = glm::vec3(-foliR, 0, -foliR);
    wom.boundMax = glm::vec3( foliR, foliCY + foliR, foliR);
    wom.boundRadius = glm::length(wom.boundMax - wom.boundMin) * 0.5f;
    wowee::pipeline::WoweeModel::Batch b;
    b.indexStart = 0;
    b.indexCount = static_cast<uint32_t>(wom.indices.size());
    b.textureIndex = 0;
    b.blendMode = 0;
    b.flags = 0;
    wom.batches.push_back(b);
    wom.texturePaths.push_back("");
    std::filesystem::path womPath(womBase);
    std::filesystem::create_directories(womPath.parent_path());
    if (!wowee::pipeline::WoweeModelLoader::save(wom, womBase)) {
        std::fprintf(stderr,
            "gen-mesh-tree: failed to save %s.wom\n", womBase.c_str());
        return 1;
    }
    std::printf("Wrote %s.wom\n", womBase.c_str());
    std::printf("  trunk R   : %.3f\n", trunkR);
    std::printf("  trunk H   : %.3f\n", trunkH);
    std::printf("  foliage R : %.3f\n", foliR);
    std::printf("  total H   : %.3f\n", foliCY + foliR);
    std::printf("  vertices  : %zu\n", wom.vertices.size());
    std::printf("  triangles : %zu\n", wom.indices.size() / 3);
    return 0;
}

int handleMeshDispatch(int& i, int argc, char** argv) {
    // Synthesize a procedural primitive WOM. Generates proper
    // per-face normals, planar UVs, a bounding box, and a
    // single batch covering all indices so the model renders
    // immediately in the editor without further processing.
    //
    // Shapes:
    //   cube   — 24 verts / 12 tris, axis-aligned, ±size/2
    //   plane  — 4 verts / 2 tris, on XY plane (Z=0), ±size/2
    //   sphere — UV sphere, 16 segments × 12 stacks, radius=size/2
    std::string womBase = argv[++i];
    std::string shape = argv[++i];
    float size = 1.0f;
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { size = std::stof(argv[++i]); } catch (...) {}
    }
    if (size <= 0.0f) {
        std::fprintf(stderr,
            "gen-mesh: size must be positive (got %g)\n", size);
        return 1;
    }
    // Strip .wom if user passed a full filename — saver expects base.
    if (womBase.size() >= 4 &&
        womBase.substr(womBase.size() - 4) == ".wom") {
        womBase = womBase.substr(0, womBase.size() - 4);
    }
    wowee::pipeline::WoweeModel wom;
    wom.name = std::filesystem::path(womBase).stem().string();
    wom.version = 3;
    // Helper to push a vertex with explicit normal + uv.
    auto addVertex = [&](float x, float y, float z,
                          float nx, float ny, float nz,
                          float u, float v) -> uint32_t {
        wowee::pipeline::WoweeModel::Vertex vtx;
        vtx.position = glm::vec3(x, y, z);
        vtx.normal = glm::vec3(nx, ny, nz);
        vtx.texCoord = glm::vec2(u, v);
        wom.vertices.push_back(vtx);
        return static_cast<uint32_t>(wom.vertices.size() - 1);
    };
    std::string s = shape;
    std::transform(s.begin(), s.end(), s.begin(),
                   [](unsigned char c) { return std::tolower(c); });
    float h = size * 0.5f;
    if (s == "cube") {
        // 6 faces, 4 verts each (so per-face normals are flat).
        struct Face { float nx, ny, nz; float verts[4][3]; };
        Face faces[6] = {
            { 0,  0,  1, {{-h,-h, h},{ h,-h, h},{ h, h, h},{-h, h, h}}},  // +Z
            { 0,  0, -1, {{ h,-h,-h},{-h,-h,-h},{-h, h,-h},{ h, h,-h}}},  // -Z
            { 1,  0,  0, {{ h,-h, h},{ h,-h,-h},{ h, h,-h},{ h, h, h}}},  // +X
            {-1,  0,  0, {{-h,-h,-h},{-h,-h, h},{-h, h, h},{-h, h,-h}}},  // -X
            { 0,  1,  0, {{-h, h, h},{ h, h, h},{ h, h,-h},{-h, h,-h}}},  // +Y
            { 0, -1,  0, {{-h,-h,-h},{ h,-h,-h},{ h,-h, h},{-h,-h, h}}},  // -Y
        };
        float uvs[4][2] = {{0,0},{1,0},{1,1},{0,1}};
        for (auto& f : faces) {
            uint32_t base = static_cast<uint32_t>(wom.vertices.size());
            for (int k = 0; k < 4; ++k) {
                addVertex(f.verts[k][0], f.verts[k][1], f.verts[k][2],
                          f.nx, f.ny, f.nz, uvs[k][0], uvs[k][1]);
            }
            wom.indices.push_back(base + 0);
            wom.indices.push_back(base + 1);
            wom.indices.push_back(base + 2);
            wom.indices.push_back(base + 0);
            wom.indices.push_back(base + 2);
            wom.indices.push_back(base + 3);
        }
    } else if (s == "plane") {
        addVertex(-h, -h, 0,  0, 0, 1,  0, 0);
        addVertex( h, -h, 0,  0, 0, 1,  1, 0);
        addVertex( h,  h, 0,  0, 0, 1,  1, 1);
        addVertex(-h,  h, 0,  0, 0, 1,  0, 1);
        wom.indices = {0, 1, 2, 0, 2, 3};
    } else if (s == "sphere") {
        const int segments = 16;
        const int stacks = 12;
        float r = h;
        for (int st = 0; st <= stacks; ++st) {
            float v = static_cast<float>(st) / stacks;
            float phi = v * 3.14159265358979f;
            float sphi = std::sin(phi), cphi = std::cos(phi);
            for (int sg = 0; sg <= segments; ++sg) {
                float u = static_cast<float>(sg) / segments;
                float theta = u * 2.0f * 3.14159265358979f;
                float stheta = std::sin(theta), ctheta = std::cos(theta);
                float nx = sphi * ctheta;
                float ny = sphi * stheta;
                float nz = cphi;
                addVertex(r * nx, r * ny, r * nz, nx, ny, nz, u, v);
            }
        }
        int stride = segments + 1;
        for (int st = 0; st < stacks; ++st) {
            for (int sg = 0; sg < segments; ++sg) {
                uint32_t a = st * stride + sg;
                uint32_t b = a + 1;
                uint32_t c = a + stride;
                uint32_t d = c + 1;
                wom.indices.push_back(a);
                wom.indices.push_back(c);
                wom.indices.push_back(b);
                wom.indices.push_back(b);
                wom.indices.push_back(c);
                wom.indices.push_back(d);
            }
        }
    } else if (s == "cylinder") {
        // Capped cylinder along the Y axis. radius=size/2,
        // height=size. 24 side segments — smooth enough for
        // pillars and torches without exploding the vertex
        // count. UVs: side wraps the texture once around;
        // caps map [0..1] from a square sampled at the disc.
        const int segments = 24;
        float r = h;
        // Side ring: 2 vertex rows (top, bottom), each with
        // (segments+1) verts so UV-seam doesn't share verts.
        for (int sg = 0; sg <= segments; ++sg) {
            float u = static_cast<float>(sg) / segments;
            float ang = u * 2.0f * 3.14159265358979f;
            float ca = std::cos(ang), sa = std::sin(ang);
            // Bottom ring (Y = -h).
            addVertex(r * ca, -h, r * sa, ca, 0, sa, u, 0);
            // Top ring (Y = +h).
            addVertex(r * ca,  h, r * sa, ca, 0, sa, u, 1);
        }
        // Side quad indices.
        for (int sg = 0; sg < segments; ++sg) {
            uint32_t a = sg * 2;
            uint32_t b = a + 1;
            uint32_t c = a + 2;
            uint32_t d = a + 3;
            wom.indices.push_back(a);
            wom.indices.push_back(c);
            wom.indices.push_back(b);
            wom.indices.push_back(b);
            wom.indices.push_back(c);
            wom.indices.push_back(d);
        }
        // Top cap fan.
        uint32_t topCenter = static_cast<uint32_t>(wom.vertices.size());
        addVertex(0, h, 0, 0, 1, 0, 0.5f, 0.5f);
        uint32_t topRingStart = static_cast<uint32_t>(wom.vertices.size());
        for (int sg = 0; sg <= segments; ++sg) {
            float u = static_cast<float>(sg) / segments;
            float ang = u * 2.0f * 3.14159265358979f;
            float ca = std::cos(ang), sa = std::sin(ang);
            addVertex(r * ca, h, r * sa, 0, 1, 0,
                       0.5f + 0.5f * ca, 0.5f + 0.5f * sa);
        }
        for (int sg = 0; sg < segments; ++sg) {
            wom.indices.push_back(topCenter);
            wom.indices.push_back(topRingStart + sg);
            wom.indices.push_back(topRingStart + sg + 1);
        }
        // Bottom cap fan (winding flipped so normal points -Y).
        uint32_t botCenter = static_cast<uint32_t>(wom.vertices.size());
        addVertex(0, -h, 0, 0, -1, 0, 0.5f, 0.5f);
        uint32_t botRingStart = static_cast<uint32_t>(wom.vertices.size());
        for (int sg = 0; sg <= segments; ++sg) {
            float u = static_cast<float>(sg) / segments;
            float ang = u * 2.0f * 3.14159265358979f;
            float ca = std::cos(ang), sa = std::sin(ang);
            addVertex(r * ca, -h, r * sa, 0, -1, 0,
                       0.5f + 0.5f * ca, 0.5f - 0.5f * sa);
        }
        for (int sg = 0; sg < segments; ++sg) {
            wom.indices.push_back(botCenter);
            wom.indices.push_back(botRingStart + sg + 1);
            wom.indices.push_back(botRingStart + sg);
        }
    } else if (s == "torus") {
        // Torus around the Y axis. Major radius (ring center
        // distance from origin) = size/2, minor radius (tube
        // thickness) = size/8 — the 4:1 ratio reads as a
        // ring rather than a fat donut. 32 ring segments × 16
        // tube segments = ~544 verts / ~1024 tris.
        const int ringSeg = 32;
        const int tubeSeg = 16;
        float R = h;          // major radius
        float r = h * 0.25f;  // minor radius (h/4)
        for (int i2 = 0; i2 <= ringSeg; ++i2) {
            float u = static_cast<float>(i2) / ringSeg;
            float theta = u * 2.0f * 3.14159265358979f;
            float ct = std::cos(theta), st = std::sin(theta);
            for (int j2 = 0; j2 <= tubeSeg; ++j2) {
                float v = static_cast<float>(j2) / tubeSeg;
                float phi = v * 2.0f * 3.14159265358979f;
                float cp = std::cos(phi), sp = std::sin(phi);
                // Position on the surface.
                float x = (R + r * cp) * ct;
                float y = r * sp;
                float z = (R + r * cp) * st;
                // Normal: from the tube center outward.
                float nx = cp * ct;
                float ny = sp;
                float nz = cp * st;
                addVertex(x, y, z, nx, ny, nz, u, v);
            }
        }
        int stride = tubeSeg + 1;
        for (int i2 = 0; i2 < ringSeg; ++i2) {
            for (int j2 = 0; j2 < tubeSeg; ++j2) {
                uint32_t a = i2 * stride + j2;
                uint32_t b = a + 1;
                uint32_t c = a + stride;
                uint32_t d = c + 1;
                wom.indices.push_back(a);
                wom.indices.push_back(c);
                wom.indices.push_back(b);
                wom.indices.push_back(b);
                wom.indices.push_back(c);
                wom.indices.push_back(d);
            }
        }
    } else if (s == "cone") {
        // Cone with apex at +Y. radius=size/2, height=size.
        // 24 side segments. Side has smooth radial-ish normals
        // (slanted up by half the slope angle) for a curved
        // shaded surface; bottom cap has flat -Y normal.
        const int segments = 24;
        float r = h;
        float H = size;
        // Slant length used for the side normal Y component.
        // Side normal direction: (cos(a), nyComponent, sin(a))
        // where the slope is r/H per unit of horizontal travel.
        // Normalize so the normal has unit length.
        float sideXZScale = H / std::sqrt(H * H + r * r);
        float sideY = r / std::sqrt(H * H + r * r);
        // Side ring (apex repeated per segment so each tri has
        // its own apex vertex with the correct normal).
        for (int sg = 0; sg <= segments; ++sg) {
            float u = static_cast<float>(sg) / segments;
            float ang = u * 2.0f * 3.14159265358979f;
            float ca = std::cos(ang), sa = std::sin(ang);
            // Base vertex (Y = 0).
            addVertex(r * ca, 0.0f, r * sa,
                       sideXZScale * ca, sideY, sideXZScale * sa,
                       u, 1.0f);
            // Apex vertex (Y = H), one per ring step so the
            // top vertex carries the segment-specific normal.
            addVertex(0.0f, H, 0.0f,
                       sideXZScale * ca, sideY, sideXZScale * sa,
                       u, 0.0f);
        }
        // Side triangle indices.
        for (int sg = 0; sg < segments; ++sg) {
            uint32_t base = sg * 2;
            // Two tris per quad band. The apex collapses to a
            // point, so really one triangle per segment, but
            // emitting both keeps the indexing uniform across
            // the cylinder/cone code paths.
            uint32_t a = base + 0;     // base k
            uint32_t b = base + 1;     // apex k
            uint32_t c = base + 2;     // base k+1
            uint32_t d = base + 3;     // apex k+1
            wom.indices.push_back(a);
            wom.indices.push_back(c);
            wom.indices.push_back(b);
            // Second triangle would be (b,c,d) but b == d at
            // the apex visually — we still emit it so the
            // per-vertex normals on b and d shade the joining
            // seam smoothly.
            wom.indices.push_back(b);
            wom.indices.push_back(c);
            wom.indices.push_back(d);
        }
        // Bottom cap fan (flat -Y normal).
        uint32_t botCenter = static_cast<uint32_t>(wom.vertices.size());
        addVertex(0.0f, 0.0f, 0.0f, 0.0f, -1.0f, 0.0f, 0.5f, 0.5f);
        uint32_t botRingStart = static_cast<uint32_t>(wom.vertices.size());
        for (int sg = 0; sg <= segments; ++sg) {
            float u = static_cast<float>(sg) / segments;
            float ang = u * 2.0f * 3.14159265358979f;
            float ca = std::cos(ang), sa = std::sin(ang);
            addVertex(r * ca, 0.0f, r * sa, 0.0f, -1.0f, 0.0f,
                       0.5f + 0.5f * ca, 0.5f - 0.5f * sa);
        }
        for (int sg = 0; sg < segments; ++sg) {
            wom.indices.push_back(botCenter);
            wom.indices.push_back(botRingStart + sg + 1);
            wom.indices.push_back(botRingStart + sg);
        }
    } else if (s == "ramp") {
        // Right-triangular prism: a wedge that climbs along
        // +X. Footprint is size×size on XY (centered on origin
        // in X, Y from 0 to size); rises from Z=0 at -X to
        // Z=size at +X. Useful for ramps onto platforms,
        // simple roof slopes, cliff faces.
        //
        // 6 verts × 5 faces = 18 verts so per-face normals
        // stay flat: top slope, bottom, back-tall, +Y side,
        // -Y side. Front-short (X = -size/2) is open since
        // the ramp meets ground there at zero height.
        // Actually we still emit 5 faces — the "front" edge
        // is just where slope and ground meet, no separate
        // face needed.
        float xMin = -h, xMax = h;
        float yMin = 0,  yMax = size;
        float zMin = 0,  zMax = size;
        // Faces: top slope (normal = normalize(-1,0,1) since
        // the slope rises with +X going up, normal points
        // up-and-back).
        float slopeLen = std::sqrt(size * size + size * size);
        float nSlopeX = -size / slopeLen;
        float nSlopeZ =  size / slopeLen;
        struct Face { float nx, ny, nz; float verts[4][3]; };
        Face faces[5] = {
            // Top sloped quad: from (xMin, yMin, zMin) up to
            // (xMax, yMin/yMax, zMax)
            { nSlopeX, 0, nSlopeZ,
               {{xMin, yMin, zMin},{xMin, yMax, zMin},
                {xMax, yMax, zMax},{xMax, yMin, zMax}}},
            // Bottom (-Z normal)
            { 0, 0, -1,
               {{xMin, yMin, zMin},{xMax, yMin, zMin},
                {xMax, yMax, zMin},{xMin, yMax, zMin}}},
            // Back-tall vertical wall (+X)
            { 1, 0, 0,
               {{xMax, yMin, zMin},{xMax, yMin, zMax},
                {xMax, yMax, zMax},{xMax, yMax, zMin}}},
            // -Y side triangle (degenerate quad — last 2 verts
            // collapse to a point — but indexing uniformly is
            // simpler than a special tri path)
            { 0, -1, 0,
               {{xMin, yMin, zMin},{xMax, yMin, zMin},
                {xMax, yMin, zMax},{xMax, yMin, zMax}}},
            // +Y side triangle (same shape mirrored)
            { 0, 1, 0,
               {{xMin, yMax, zMin},{xMax, yMax, zMax},
                {xMax, yMax, zMin},{xMax, yMax, zMin}}},
        };
        float uvs[4][2] = {{0,0},{1,0},{1,1},{0,1}};
        for (auto& f : faces) {
            uint32_t base = static_cast<uint32_t>(wom.vertices.size());
            for (int k = 0; k < 4; ++k) {
                addVertex(f.verts[k][0], f.verts[k][1], f.verts[k][2],
                           f.nx, f.ny, f.nz, uvs[k][0], uvs[k][1]);
            }
            wom.indices.push_back(base + 0);
            wom.indices.push_back(base + 1);
            wom.indices.push_back(base + 2);
            wom.indices.push_back(base + 0);
            wom.indices.push_back(base + 2);
            wom.indices.push_back(base + 3);
        }
    } else {
        std::fprintf(stderr,
            "gen-mesh: shape must be cube, plane, sphere, cylinder, torus, cone, or ramp (got '%s')\n",
            shape.c_str());
        return 1;
    }
    // Compute bounds from the vertex positions we just emitted.
    wom.boundMin = glm::vec3(1e30f);
    wom.boundMax = glm::vec3(-1e30f);
    for (const auto& v : wom.vertices) {
        wom.boundMin = glm::min(wom.boundMin, v.position);
        wom.boundMax = glm::max(wom.boundMax, v.position);
    }
    wom.boundRadius = glm::length(wom.boundMax - wom.boundMin) * 0.5f;
    // Single material batch covering everything — keeps the
    // model immediately renderable.
    wowee::pipeline::WoweeModel::Batch b;
    b.indexStart = 0;
    b.indexCount = static_cast<uint32_t>(wom.indices.size());
    b.textureIndex = 0;
    b.blendMode = 0;
    b.flags = 0;
    wom.batches.push_back(b);
    // Empty texture path slot so batch.textureIndex=0 is a
    // valid index into texturePaths. The user can later set a
    // real path or run --gen-texture next to it.
    wom.texturePaths.push_back("");
    std::filesystem::path womPath(womBase);
    std::filesystem::create_directories(womPath.parent_path());
    if (!wowee::pipeline::WoweeModelLoader::save(wom, womBase)) {
        std::fprintf(stderr,
            "gen-mesh: failed to save %s.wom\n", womBase.c_str());
        return 1;
    }
    std::printf("Wrote %s.wom\n", womBase.c_str());
    std::printf("  shape    : %s\n", s.c_str());
    std::printf("  size     : %.3f\n", size);
    std::printf("  vertices : %zu\n", wom.vertices.size());
    std::printf("  indices  : %zu (%zu tri%s)\n",
                wom.indices.size(), wom.indices.size() / 3,
                wom.indices.size() / 3 == 1 ? "" : "s");
    std::printf("  bounds   : (%.3f, %.3f, %.3f) - (%.3f, %.3f, %.3f)\n",
                wom.boundMin.x, wom.boundMin.y, wom.boundMin.z,
                wom.boundMax.x, wom.boundMax.y, wom.boundMax.z);
    return 0;
}

int handleTextured(int& i, int argc, char** argv) {
    // One-shot composer: --gen-mesh + --gen-texture wired
    // together so the resulting WOM's texturePaths[0] points
    // at the freshly-written PNG sidecar. Output is a model
    // that renders with the synthesized texture out of the
    // box — useful for prototyping textured props without
    // chaining three commands by hand.
    //
    // The texture is written next to the mesh as
    //   <wom-base>.png
    // and the WOM's texturePaths[0] is set to that filename
    // (just the leaf — runtime resolves it relative to the
    // model's own directory).
    std::string womBase = argv[++i];
    std::string shape = argv[++i];
    std::string colorSpec = argv[++i];
    std::string sizeArg;
    if (i + 1 < argc && argv[i + 1][0] != '-') sizeArg = argv[++i];
    // Strip .wom if user passed full filename.
    if (womBase.size() >= 4 &&
        womBase.substr(womBase.size() - 4) == ".wom") {
        womBase = womBase.substr(0, womBase.size() - 4);
    }
    std::string self = argv[0];
    // 1) Mesh.
    std::string meshCmd = "\"" + self + "\" --gen-mesh \"" + womBase +
                           "\" " + shape;
    if (!sizeArg.empty()) meshCmd += " " + sizeArg;
    meshCmd += " >/dev/null 2>&1";
    int rc = std::system(meshCmd.c_str());
    if (rc != 0) {
        std::fprintf(stderr,
            "gen-mesh-textured: gen-mesh step failed (rc=%d)\n", rc);
        return 1;
    }
    // 2) Texture as a PNG sidecar at the mesh's base path.
    std::string pngPath = womBase + ".png";
    std::string texCmd = "\"" + self + "\" --gen-texture \"" + pngPath +
                          "\" \"" + colorSpec + "\" 256 256";
    texCmd += " >/dev/null 2>&1";
    rc = std::system(texCmd.c_str());
    if (rc != 0) {
        std::fprintf(stderr,
            "gen-mesh-textured: gen-texture step failed (rc=%d)\n", rc);
        return 1;
    }
    // 3) Load the WOM, set texturePaths[0] to the PNG leaf,
    //    and re-save so the binding is permanent.
    auto wom = wowee::pipeline::WoweeModelLoader::load(womBase);
    if (!wom.isValid()) {
        std::fprintf(stderr,
            "gen-mesh-textured: cannot load %s.wom after gen-mesh\n",
            womBase.c_str());
        return 1;
    }
    std::string pngLeaf = std::filesystem::path(pngPath).filename().string();
    if (wom.texturePaths.empty()) {
        wom.texturePaths.push_back(pngLeaf);
    } else {
        wom.texturePaths[0] = pngLeaf;
    }
    if (!wowee::pipeline::WoweeModelLoader::save(wom, womBase)) {
        std::fprintf(stderr,
            "gen-mesh-textured: failed to re-save %s.wom\n",
            womBase.c_str());
        return 1;
    }
    std::printf("Wrote %s.wom + %s\n", womBase.c_str(), pngPath.c_str());
    std::printf("  shape    : %s\n", shape.c_str());
    std::printf("  color    : %s\n", colorSpec.c_str());
    std::printf("  vertices : %zu\n", wom.vertices.size());
    std::printf("  texture  : %s (wired into batch 0)\n", pngLeaf.c_str());
    return 0;
}

int handleMushroom(int& i, int argc, char** argv) {
    // Mushroom: cylindrical stalk + UV-sphere top half (cap).
    // Cap radius is independent so users get the classic
    // narrow-stalk-wide-cap silhouette of a forest mushroom.
    // The 29th procedural mesh primitive.
    std::string womBase = argv[++i];
    float stalkR = 0.1f;
    float stalkH = 0.6f;
    float capR = 0.4f;
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { stalkR = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { stalkH = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { capR = std::stof(argv[++i]); } catch (...) {}
    }
    if (stalkR <= 0 || stalkH <= 0 || capR <= 0) {
        std::fprintf(stderr,
            "gen-mesh-mushroom: all dims must be positive\n");
        return 1;
    }
    if (womBase.size() >= 4 &&
        womBase.substr(womBase.size() - 4) == ".wom") {
        womBase = womBase.substr(0, womBase.size() - 4);
    }
    wowee::pipeline::WoweeModel wom;
    wom.name = std::filesystem::path(womBase).stem().string();
    wom.version = 3;
    const float pi = 3.14159265358979f;
    auto addV = [&](glm::vec3 p, glm::vec3 n, glm::vec2 uv) -> uint32_t {
        wowee::pipeline::WoweeModel::Vertex vtx;
        vtx.position = p; vtx.normal = n; vtx.texCoord = uv;
        wom.vertices.push_back(vtx);
        return static_cast<uint32_t>(wom.vertices.size() - 1);
    };
    // Stalk: 12-segment cylinder from y=0 to y=stalkH.
    const int segs = 12;
    uint32_t bot = static_cast<uint32_t>(wom.vertices.size());
    for (int sg = 0; sg <= segs; ++sg) {
        float u = static_cast<float>(sg) / segs;
        float ang = u * 2.0f * pi;
        glm::vec3 p(stalkR * std::cos(ang), 0, stalkR * std::sin(ang));
        glm::vec3 n(std::cos(ang), 0, std::sin(ang));
        addV(p, n, {u, 0});
    }
    uint32_t top = static_cast<uint32_t>(wom.vertices.size());
    for (int sg = 0; sg <= segs; ++sg) {
        float u = static_cast<float>(sg) / segs;
        float ang = u * 2.0f * pi;
        glm::vec3 p(stalkR * std::cos(ang), stalkH,
                    stalkR * std::sin(ang));
        glm::vec3 n(std::cos(ang), 0, std::sin(ang));
        addV(p, n, {u, 1});
    }
    for (int sg = 0; sg < segs; ++sg) {
        wom.indices.insert(wom.indices.end(), {
            bot + sg, top + sg, bot + sg + 1,
            bot + sg + 1, top + sg, top + sg + 1
        });
    }
    // Bottom cap (faces -Y) so the stalk is closed
    uint32_t bc = addV({0, 0, 0}, {0, -1, 0}, {0.5f, 0.5f});
    for (int sg = 0; sg < segs; ++sg) {
        wom.indices.insert(wom.indices.end(),
            {bc, bot + sg + 1, bot + sg});
    }
    // Cap: top half of UV sphere centered at (0, stalkH, 0).
    // Latitude 0..pi/2 (top hemisphere only). 16 longitude × 8
    // latitude segments.
    const int capLon = 16;
    const int capLat = 8;
    uint32_t capStart = static_cast<uint32_t>(wom.vertices.size());
    for (int la = 0; la <= capLat; ++la) {
        float v = static_cast<float>(la) / capLat;
        float phi = (1.0f - v) * pi * 0.5f;  // pi/2 down to 0
        float sphi = std::sin(phi), cphi = std::cos(phi);
        for (int lo = 0; lo <= capLon; ++lo) {
            float u = static_cast<float>(lo) / capLon;
            float theta = u * 2.0f * pi;
            glm::vec3 dir(cphi * std::cos(theta),
                          sphi,
                          cphi * std::sin(theta));
            glm::vec3 p(dir.x * capR, stalkH + dir.y * capR,
                        dir.z * capR);
            addV(p, dir, {u, v});
        }
    }
    int rowSize = capLon + 1;
    for (int la = 0; la < capLat; ++la) {
        for (int lo = 0; lo < capLon; ++lo) {
            uint32_t i00 = capStart + la * rowSize + lo;
            uint32_t i01 = capStart + la * rowSize + lo + 1;
            uint32_t i10 = capStart + (la + 1) * rowSize + lo;
            uint32_t i11 = capStart + (la + 1) * rowSize + lo + 1;
            wom.indices.insert(wom.indices.end(),
                {i00, i10, i01, i01, i10, i11});
        }
    }
    // Underside of cap (the "gills" disc, faces -Y) so the
    // mushroom is watertight viewed from below.
    uint32_t capBot = addV({0, stalkH, 0}, {0, -1, 0}, {0.5f, 0.5f});
    for (int sg = 0; sg < capLon; ++sg) {
        uint32_t edge0 = capStart + capLat * rowSize + sg;
        uint32_t edge1 = capStart + capLat * rowSize + sg + 1;
        wom.indices.insert(wom.indices.end(),
            {capBot, edge1, edge0});
    }
    wowee::pipeline::WoweeModel::Batch batch;
    batch.indexStart = 0;
    batch.indexCount = static_cast<uint32_t>(wom.indices.size());
    batch.textureIndex = 0;
    wom.batches.push_back(batch);
    float maxY = stalkH + capR;
    wom.boundMin = glm::vec3(-capR, 0, -capR);
    wom.boundMax = glm::vec3( capR, maxY, capR);
    if (!wowee::pipeline::WoweeModelLoader::save(wom, womBase)) {
        std::fprintf(stderr,
            "gen-mesh-mushroom: failed to save %s.wom\n", womBase.c_str());
        return 1;
    }
    std::printf("Wrote %s.wom\n", womBase.c_str());
    std::printf("  stalk     : R=%.3f H=%.3f\n", stalkR, stalkH);
    std::printf("  cap       : R=%.3f\n", capR);
    std::printf("  total H   : %.3f\n", maxY);
    std::printf("  vertices  : %zu\n", wom.vertices.size());
    std::printf("  triangles : %zu\n", wom.indices.size() / 3);
    return 0;
}

int handleCart(int& i, int argc, char** argv) {
    // Wooden cart: rectangular bed box + 2 cylindrical wheels
    // mounted axis-along-Z on the sides at the bottom of the
    // bed. Wheels are full cylinders (16-segment) so the round
    // silhouette reads from any angle. The 30th procedural mesh
    // primitive.
    std::string womBase = argv[++i];
    float bedLen = 1.6f;     // along X (cart length)
    float bedWidth = 0.8f;   // along Z
    float bedH = 0.5f;       // bed height (Y)
    float wheelR = 0.35f;    // wheel radius
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { bedLen = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { bedWidth = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { bedH = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { wheelR = std::stof(argv[++i]); } catch (...) {}
    }
    if (bedLen <= 0 || bedWidth <= 0 || bedH <= 0 || wheelR <= 0) {
        std::fprintf(stderr,
            "gen-mesh-cart: all dims must be positive\n");
        return 1;
    }
    if (womBase.size() >= 4 &&
        womBase.substr(womBase.size() - 4) == ".wom") {
        womBase = womBase.substr(0, womBase.size() - 4);
    }
    wowee::pipeline::WoweeModel wom;
    wom.name = std::filesystem::path(womBase).stem().string();
    wom.version = 3;
    const float pi = 3.14159265358979f;
    auto addV = [&](glm::vec3 p, glm::vec3 n, glm::vec2 uv) -> uint32_t {
        wowee::pipeline::WoweeModel::Vertex vtx;
        vtx.position = p; vtx.normal = n; vtx.texCoord = uv;
        wom.vertices.push_back(vtx);
        return static_cast<uint32_t>(wom.vertices.size() - 1);
    };
    auto addBox = [&](float cx, float cy, float cz,
                      float hx, float hy, float hz) {
        struct Face { glm::vec3 n, du, dv; };
        Face faces[6] = {
            {{0, 1, 0}, {1, 0, 0}, {0, 0, 1}},
            {{0,-1, 0}, {1, 0, 0}, {0, 0,-1}},
            {{1, 0, 0}, {0, 0, 1}, {0, 1, 0}},
            {{-1,0, 0}, {0, 0,-1}, {0, 1, 0}},
            {{0, 0, 1}, {-1,0, 0}, {0, 1, 0}},
            {{0, 0,-1}, {1, 0, 0}, {0, 1, 0}},
        };
        glm::vec3 c(cx, cy, cz);
        glm::vec3 ext(hx, hy, hz);
        for (const Face& f : faces) {
            glm::vec3 center = c + glm::vec3(f.n.x*hx, f.n.y*hy, f.n.z*hz);
            glm::vec3 du = glm::vec3(f.du.x*ext.x, f.du.y*ext.y, f.du.z*ext.z);
            glm::vec3 dv = glm::vec3(f.dv.x*ext.x, f.dv.y*ext.y, f.dv.z*ext.z);
            uint32_t base = static_cast<uint32_t>(wom.vertices.size());
            auto push = [&](glm::vec3 p, float u, float v) {
                wowee::pipeline::WoweeModel::Vertex vtx;
                vtx.position = p; vtx.normal = f.n; vtx.texCoord = {u, v};
                wom.vertices.push_back(vtx);
            };
            push(center - du - dv, 0, 0);
            push(center + du - dv, 1, 0);
            push(center + du + dv, 1, 1);
            push(center - du + dv, 0, 1);
            wom.indices.insert(wom.indices.end(),
                {base, base + 1, base + 2, base, base + 2, base + 3});
        }
    };
    // Bed sits at y = wheelR (so wheels touch ground at y=0)
    // up to y = wheelR + bedH.
    float bedY = wheelR + bedH * 0.5f;
    addBox(0, bedY, 0, bedLen * 0.5f, bedH * 0.5f, bedWidth * 0.5f);
    // Wheels: cylinder with axis along Z, mounted on each side
    // of the bed. Each wheel has 16 angular segments + 2 caps.
    const int wheelSegs = 16;
    float wheelThick = bedWidth * 0.08f;  // wheel thickness (along Z)
    float wheelOffsetZ = bedWidth * 0.5f + wheelThick * 0.5f;
    auto addWheel = [&](float cz) {
        // Front face (z = cz + wheelThick/2)
        float zFront = cz + wheelThick * 0.5f;
        float zBack = cz - wheelThick * 0.5f;
        uint32_t frontStart = static_cast<uint32_t>(wom.vertices.size());
        for (int sg = 0; sg <= wheelSegs; ++sg) {
            float u = static_cast<float>(sg) / wheelSegs;
            float ang = u * 2.0f * pi;
            glm::vec3 p(wheelR * std::cos(ang), wheelR + wheelR * std::sin(ang), zFront);
            addV(p, {0, 0, 1}, {0.5f + 0.5f * std::cos(ang),
                                 0.5f + 0.5f * std::sin(ang)});
        }
        uint32_t backStart = static_cast<uint32_t>(wom.vertices.size());
        for (int sg = 0; sg <= wheelSegs; ++sg) {
            float u = static_cast<float>(sg) / wheelSegs;
            float ang = u * 2.0f * pi;
            glm::vec3 p(wheelR * std::cos(ang), wheelR + wheelR * std::sin(ang), zBack);
            addV(p, {0, 0, -1}, {0.5f + 0.5f * std::cos(ang),
                                  0.5f + 0.5f * std::sin(ang)});
        }
        // Front cap fan
        uint32_t fc = addV({0, wheelR, zFront}, {0, 0, 1}, {0.5f, 0.5f});
        for (int sg = 0; sg < wheelSegs; ++sg) {
            wom.indices.insert(wom.indices.end(),
                {fc, frontStart + sg, frontStart + sg + 1});
        }
        // Back cap fan (reversed winding)
        uint32_t bc = addV({0, wheelR, zBack}, {0, 0, -1}, {0.5f, 0.5f});
        for (int sg = 0; sg < wheelSegs; ++sg) {
            wom.indices.insert(wom.indices.end(),
                {bc, backStart + sg + 1, backStart + sg});
        }
        // Side ring: connect each pair of front/back rim verts
        // with a quad. Side normals point outward radially.
        for (int sg = 0; sg < wheelSegs; ++sg) {
            float u = static_cast<float>(sg) / wheelSegs;
            float ang = u * 2.0f * pi;
            float u2 = static_cast<float>(sg + 1) / wheelSegs;
            float ang2 = u2 * 2.0f * pi;
            glm::vec3 n0(std::cos(ang), std::sin(ang), 0);
            glm::vec3 n1(std::cos(ang2), std::sin(ang2), 0);
            uint32_t a = addV({wheelR * std::cos(ang), wheelR + wheelR * std::sin(ang), zFront}, n0, {u, 0});
            uint32_t b = addV({wheelR * std::cos(ang), wheelR + wheelR * std::sin(ang), zBack}, n0, {u, 1});
            uint32_t c = addV({wheelR * std::cos(ang2), wheelR + wheelR * std::sin(ang2), zBack}, n1, {u2, 1});
            uint32_t d = addV({wheelR * std::cos(ang2), wheelR + wheelR * std::sin(ang2), zFront}, n1, {u2, 0});
            wom.indices.insert(wom.indices.end(),
                {a, b, c, a, c, d});
        }
    };
    addWheel( wheelOffsetZ);
    addWheel(-wheelOffsetZ);
    wowee::pipeline::WoweeModel::Batch batch;
    batch.indexStart = 0;
    batch.indexCount = static_cast<uint32_t>(wom.indices.size());
    batch.textureIndex = 0;
    wom.batches.push_back(batch);
    float maxY = wheelR + bedH;
    float maxZ = wheelOffsetZ + wheelThick * 0.5f;
    wom.boundMin = glm::vec3(-bedLen * 0.5f, 0, -maxZ);
    wom.boundMax = glm::vec3( bedLen * 0.5f, std::max(maxY, 2 * wheelR), maxZ);
    if (!wowee::pipeline::WoweeModelLoader::save(wom, womBase)) {
        std::fprintf(stderr,
            "gen-mesh-cart: failed to save %s.wom\n", womBase.c_str());
        return 1;
    }
    std::printf("Wrote %s.wom\n", womBase.c_str());
    std::printf("  bed       : %.3f × %.3f × %.3f\n",
                bedLen, bedWidth, bedH);
    std::printf("  wheels    : 2 × R=%.3f thickness=%.3f\n",
                wheelR, wheelThick);
    std::printf("  vertices  : %zu\n", wom.vertices.size());
    std::printf("  triangles : %zu\n", wom.indices.size() / 3);
    return 0;
}

int handleBanner(int& i, int argc, char** argv) {
    // Banner: vertical pole + rectangular flag hanging off it.
    // Pole is a 12-segment cylinder along Y. Flag is a flat
    // rectangle attached at the top of the pole, draped along
    // -Z. Flag has both front (+X) and back (-X) faces so it
    // reads from any viewing angle. The 31st mesh primitive.
    std::string womBase = argv[++i];
    float poleH = 3.0f;
    float poleR = 0.05f;
    float flagW = 0.8f;       // along -Z (drape direction)
    float flagH = 1.2f;       // along Y (down from top)
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { poleH = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { poleR = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { flagW = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { flagH = std::stof(argv[++i]); } catch (...) {}
    }
    if (poleH <= 0 || poleR <= 0 || flagW <= 0 || flagH <= 0 ||
        flagH > poleH) {
        std::fprintf(stderr,
            "gen-mesh-banner: all dims > 0; flagH must be <= poleH\n");
        return 1;
    }
    if (womBase.size() >= 4 &&
        womBase.substr(womBase.size() - 4) == ".wom") {
        womBase = womBase.substr(0, womBase.size() - 4);
    }
    wowee::pipeline::WoweeModel wom;
    wom.name = std::filesystem::path(womBase).stem().string();
    wom.version = 3;
    const float pi = 3.14159265358979f;
    auto addV = [&](glm::vec3 p, glm::vec3 n, glm::vec2 uv) -> uint32_t {
        wowee::pipeline::WoweeModel::Vertex vtx;
        vtx.position = p; vtx.normal = n; vtx.texCoord = uv;
        wom.vertices.push_back(vtx);
        return static_cast<uint32_t>(wom.vertices.size() - 1);
    };
    // Pole cylinder (12 segments)
    const int poleSegs = 12;
    uint32_t bot = static_cast<uint32_t>(wom.vertices.size());
    for (int sg = 0; sg <= poleSegs; ++sg) {
        float u = static_cast<float>(sg) / poleSegs;
        float ang = u * 2.0f * pi;
        glm::vec3 p(poleR * std::cos(ang), 0, poleR * std::sin(ang));
        glm::vec3 n(std::cos(ang), 0, std::sin(ang));
        addV(p, n, {u, 0});
    }
    uint32_t top = static_cast<uint32_t>(wom.vertices.size());
    for (int sg = 0; sg <= poleSegs; ++sg) {
        float u = static_cast<float>(sg) / poleSegs;
        float ang = u * 2.0f * pi;
        glm::vec3 p(poleR * std::cos(ang), poleH, poleR * std::sin(ang));
        glm::vec3 n(std::cos(ang), 0, std::sin(ang));
        addV(p, n, {u, 1});
    }
    for (int sg = 0; sg < poleSegs; ++sg) {
        wom.indices.insert(wom.indices.end(), {
            bot + sg, top + sg, bot + sg + 1,
            bot + sg + 1, top + sg, top + sg + 1
        });
    }
    // Pole top + bottom caps
    uint32_t bc = addV({0, 0, 0}, {0, -1, 0}, {0.5f, 0.5f});
    uint32_t tc = addV({0, poleH, 0}, {0, 1, 0}, {0.5f, 0.5f});
    for (int sg = 0; sg < poleSegs; ++sg) {
        wom.indices.insert(wom.indices.end(),
            {bc, bot + sg + 1, bot + sg});
        wom.indices.insert(wom.indices.end(),
            {tc, top + sg, top + sg + 1});
    }
    // Flag: rectangle from (poleR, poleH-flagH, 0) to
    // (poleR, poleH, -flagW). Two faces (front +X, back -X)
    // so it reads from both sides.
    float fy0 = poleH - flagH;
    float fy1 = poleH;
    float fz0 = 0;
    float fz1 = -flagW;
    float fx = poleR;
    glm::vec3 frontN(1, 0, 0);
    glm::vec3 backN(-1, 0, 0);
    // Front face (faces +X, looking at it from outside)
    uint32_t fa = addV({fx, fy0, fz0}, frontN, {0, 0});
    uint32_t fb = addV({fx, fy0, fz1}, frontN, {1, 0});
    uint32_t fc_ = addV({fx, fy1, fz1}, frontN, {1, 1});
    uint32_t fd = addV({fx, fy1, fz0}, frontN, {0, 1});
    wom.indices.insert(wom.indices.end(), {fa, fb, fc_, fa, fc_, fd});
    // Back face (faces -X)
    uint32_t ba = addV({fx, fy0, fz0}, backN, {0, 0});
    uint32_t bb = addV({fx, fy1, fz0}, backN, {0, 1});
    uint32_t bc_v = addV({fx, fy1, fz1}, backN, {1, 1});
    uint32_t bd = addV({fx, fy0, fz1}, backN, {1, 0});
    wom.indices.insert(wom.indices.end(), {ba, bb, bc_v, ba, bc_v, bd});
    wowee::pipeline::WoweeModel::Batch batch;
    batch.indexStart = 0;
    batch.indexCount = static_cast<uint32_t>(wom.indices.size());
    batch.textureIndex = 0;
    wom.batches.push_back(batch);
    wom.boundMin = glm::vec3(-poleR, 0, fz1);
    wom.boundMax = glm::vec3(fx + poleR, poleH, poleR);
    if (!wowee::pipeline::WoweeModelLoader::save(wom, womBase)) {
        std::fprintf(stderr,
            "gen-mesh-banner: failed to save %s.wom\n", womBase.c_str());
        return 1;
    }
    std::printf("Wrote %s.wom\n", womBase.c_str());
    std::printf("  pole       : R=%.3f H=%.3f\n", poleR, poleH);
    std::printf("  flag       : W=%.3f H=%.3f (drapes -Z)\n",
                flagW, flagH);
    std::printf("  vertices   : %zu\n", wom.vertices.size());
    std::printf("  triangles  : %zu\n", wom.indices.size() / 3);
    return 0;
}

int handleGrave(int& i, int argc, char** argv) {
    // Tombstone: low rectangular base + vertical tablet on top.
    // Tablet sits centered on the base; base is wider so the
    // grave reads with a stable foundation. The 32nd procedural
    // mesh primitive — useful for graveyards, undead zones,
    // memorial set dressing.
    std::string womBase = argv[++i];
    float tabletW = 0.6f;     // along X
    float tabletH = 1.0f;     // along Y
    float tabletT = 0.15f;    // along Z (thickness)
    float baseW = 0.8f;       // base wider than tablet
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { tabletW = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { tabletH = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { tabletT = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { baseW = std::stof(argv[++i]); } catch (...) {}
    }
    if (tabletW <= 0 || tabletH <= 0 || tabletT <= 0 || baseW <= 0 ||
        baseW < tabletW) {
        std::fprintf(stderr,
            "gen-mesh-grave: all dims > 0; baseW must be >= tabletW\n");
        return 1;
    }
    if (womBase.size() >= 4 &&
        womBase.substr(womBase.size() - 4) == ".wom") {
        womBase = womBase.substr(0, womBase.size() - 4);
    }
    wowee::pipeline::WoweeModel wom;
    wom.name = std::filesystem::path(womBase).stem().string();
    wom.version = 3;
    auto addBox = [&](float cx, float cy, float cz,
                      float hx, float hy, float hz) {
        struct Face { glm::vec3 n, du, dv; };
        Face faces[6] = {
            {{0, 1, 0}, {1, 0, 0}, {0, 0, 1}},
            {{0,-1, 0}, {1, 0, 0}, {0, 0,-1}},
            {{1, 0, 0}, {0, 0, 1}, {0, 1, 0}},
            {{-1,0, 0}, {0, 0,-1}, {0, 1, 0}},
            {{0, 0, 1}, {-1,0, 0}, {0, 1, 0}},
            {{0, 0,-1}, {1, 0, 0}, {0, 1, 0}},
        };
        glm::vec3 c(cx, cy, cz);
        glm::vec3 ext(hx, hy, hz);
        for (const Face& f : faces) {
            glm::vec3 center = c + glm::vec3(f.n.x*hx, f.n.y*hy, f.n.z*hz);
            glm::vec3 du = glm::vec3(f.du.x*ext.x, f.du.y*ext.y, f.du.z*ext.z);
            glm::vec3 dv = glm::vec3(f.dv.x*ext.x, f.dv.y*ext.y, f.dv.z*ext.z);
            uint32_t base = static_cast<uint32_t>(wom.vertices.size());
            auto push = [&](glm::vec3 p, float u, float v) {
                wowee::pipeline::WoweeModel::Vertex vtx;
                vtx.position = p; vtx.normal = f.n; vtx.texCoord = {u, v};
                wom.vertices.push_back(vtx);
            };
            push(center - du - dv, 0, 0);
            push(center + du - dv, 1, 0);
            push(center + du + dv, 1, 1);
            push(center - du + dv, 0, 1);
            wom.indices.insert(wom.indices.end(),
                {base, base + 1, base + 2, base, base + 2, base + 3});
        }
    };
    // Base: wider, lower. Sits at y=0 to baseH where baseH = 20% of tablet H.
    float baseH = tabletH * 0.2f;
    float baseDepth = tabletT * 1.5f;  // deeper than tablet for stability
    addBox(0, baseH * 0.5f, 0,
           baseW * 0.5f, baseH * 0.5f, baseDepth * 0.5f);
    // Tablet: sits on top of base, centered.
    float tabletY = baseH + tabletH * 0.5f;
    addBox(0, tabletY, 0,
           tabletW * 0.5f, tabletH * 0.5f, tabletT * 0.5f);
    wowee::pipeline::WoweeModel::Batch batch;
    batch.indexStart = 0;
    batch.indexCount = static_cast<uint32_t>(wom.indices.size());
    batch.textureIndex = 0;
    wom.batches.push_back(batch);
    float maxY = baseH + tabletH;
    float maxXZ = std::max(baseW * 0.5f, tabletW * 0.5f);
    wom.boundMin = glm::vec3(-maxXZ, 0, -baseDepth * 0.5f);
    wom.boundMax = glm::vec3( maxXZ, maxY,  baseDepth * 0.5f);
    if (!wowee::pipeline::WoweeModelLoader::save(wom, womBase)) {
        std::fprintf(stderr,
            "gen-mesh-grave: failed to save %s.wom\n", womBase.c_str());
        return 1;
    }
    std::printf("Wrote %s.wom\n", womBase.c_str());
    std::printf("  base       : %.3f × %.3f (h=%.3f)\n",
                baseW, baseDepth, baseH);
    std::printf("  tablet     : %.3f × %.3f × %.3f\n",
                tabletW, tabletH, tabletT);
    std::printf("  total H    : %.3f\n", maxY);
    std::printf("  vertices   : %zu\n", wom.vertices.size());
    std::printf("  triangles  : %zu\n", wom.indices.size() / 3);
    return 0;
}

int handleBench(int& i, int argc, char** argv) {
    // Wooden bench: long thin seat plank (X×Z plane) supported
    // by 2 leg slabs (vertical Y rectangles) at each end. Legs
    // are 90% of the bench's depth and span the full seat
    // height down to the floor. The 33rd procedural mesh
    // primitive — useful for taverns, plazas, roadside rest
    // stops.
    std::string womBase = argv[++i];
    float length = 1.5f;       // along X (bench length)
    float seatY = 0.5f;        // seat top height
    float seatT = 0.06f;       // seat plank thickness (Y)
    float seatW = 0.4f;        // seat width (Z)
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { length = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { seatY = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { seatT = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { seatW = std::stof(argv[++i]); } catch (...) {}
    }
    if (length <= 0 || seatY <= 0 || seatT <= 0 || seatW <= 0 ||
        seatT > seatY) {
        std::fprintf(stderr,
            "gen-mesh-bench: all dims > 0; seatT must be <= seatY\n");
        return 1;
    }
    if (womBase.size() >= 4 &&
        womBase.substr(womBase.size() - 4) == ".wom") {
        womBase = womBase.substr(0, womBase.size() - 4);
    }
    wowee::pipeline::WoweeModel wom;
    wom.name = std::filesystem::path(womBase).stem().string();
    wom.version = 3;
    auto addBox = [&](float cx, float cy, float cz,
                      float hx, float hy, float hz) {
        struct Face { glm::vec3 n, du, dv; };
        Face faces[6] = {
            {{0, 1, 0}, {1, 0, 0}, {0, 0, 1}},
            {{0,-1, 0}, {1, 0, 0}, {0, 0,-1}},
            {{1, 0, 0}, {0, 0, 1}, {0, 1, 0}},
            {{-1,0, 0}, {0, 0,-1}, {0, 1, 0}},
            {{0, 0, 1}, {-1,0, 0}, {0, 1, 0}},
            {{0, 0,-1}, {1, 0, 0}, {0, 1, 0}},
        };
        glm::vec3 c(cx, cy, cz);
        glm::vec3 ext(hx, hy, hz);
        for (const Face& f : faces) {
            glm::vec3 center = c + glm::vec3(f.n.x*hx, f.n.y*hy, f.n.z*hz);
            glm::vec3 du = glm::vec3(f.du.x*ext.x, f.du.y*ext.y, f.du.z*ext.z);
            glm::vec3 dv = glm::vec3(f.dv.x*ext.x, f.dv.y*ext.y, f.dv.z*ext.z);
            uint32_t base = static_cast<uint32_t>(wom.vertices.size());
            auto push = [&](glm::vec3 p, float u, float v) {
                wowee::pipeline::WoweeModel::Vertex vtx;
                vtx.position = p; vtx.normal = f.n; vtx.texCoord = {u, v};
                wom.vertices.push_back(vtx);
            };
            push(center - du - dv, 0, 0);
            push(center + du - dv, 1, 0);
            push(center + du + dv, 1, 1);
            push(center - du + dv, 0, 1);
            wom.indices.insert(wom.indices.end(),
                {base, base + 1, base + 2, base, base + 2, base + 3});
        }
    };
    // Seat: top plank at y=seatY-seatT to y=seatY.
    float seatCY = seatY - seatT * 0.5f;
    addBox(0, seatCY, 0, length * 0.5f, seatT * 0.5f, seatW * 0.5f);
    // Two leg slabs: thin Y slabs at the +X and -X ends, span
    // 90% of the seat depth, 5% of bench length thick, full
    // height from floor to bottom-of-seat.
    float legHy = (seatY - seatT) * 0.5f;
    float legCY = legHy;
    float legHx = length * 0.025f;     // ~2.5% of length on each side
    float legHz = seatW * 0.45f;
    float legX = length * 0.45f;       // legs at 90% of length out
    addBox( legX, legCY, 0, legHx, legHy, legHz);
    addBox(-legX, legCY, 0, legHx, legHy, legHz);
    wowee::pipeline::WoweeModel::Batch batch;
    batch.indexStart = 0;
    batch.indexCount = static_cast<uint32_t>(wom.indices.size());
    batch.textureIndex = 0;
    wom.batches.push_back(batch);
    wom.boundMin = glm::vec3(-length * 0.5f, 0, -seatW * 0.5f);
    wom.boundMax = glm::vec3( length * 0.5f, seatY, seatW * 0.5f);
    if (!wowee::pipeline::WoweeModelLoader::save(wom, womBase)) {
        std::fprintf(stderr,
            "gen-mesh-bench: failed to save %s.wom\n", womBase.c_str());
        return 1;
    }
    std::printf("Wrote %s.wom\n", womBase.c_str());
    std::printf("  length    : %.3f\n", length);
    std::printf("  seat Y    : %.3f (thickness %.3f)\n", seatY, seatT);
    std::printf("  seat W    : %.3f\n", seatW);
    std::printf("  legs      : 2 (at ±%.3f along X)\n", legX);
    std::printf("  vertices  : %zu\n", wom.vertices.size());
    std::printf("  triangles : %zu\n", wom.indices.size() / 3);
    return 0;
}

int handleShrine(int& i, int argc, char** argv) {
    // Small open canopy: square base + 4 cylindrical pillars
    // at the corners + a flat roof slab covering all 4. Useful
    // for wayside shrines, gazebos, well covers, market stalls.
    // The 34th procedural mesh primitive.
    std::string womBase = argv[++i];
    float size = 1.5f;          // base width = depth
    float pillarH = 2.0f;       // pillar height
    float pillarR = 0.10f;      // pillar radius
    float roofT = 0.15f;        // roof thickness
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { size = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { pillarH = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { pillarR = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { roofT = std::stof(argv[++i]); } catch (...) {}
    }
    if (size <= 0 || pillarH <= 0 || pillarR <= 0 || roofT <= 0 ||
        pillarR * 2 >= size) {
        std::fprintf(stderr,
            "gen-mesh-shrine: dims > 0; pillarR×2 must fit inside size\n");
        return 1;
    }
    if (womBase.size() >= 4 &&
        womBase.substr(womBase.size() - 4) == ".wom") {
        womBase = womBase.substr(0, womBase.size() - 4);
    }
    wowee::pipeline::WoweeModel wom;
    wom.name = std::filesystem::path(womBase).stem().string();
    wom.version = 3;
    const float pi = 3.14159265358979f;
    auto addV = [&](glm::vec3 p, glm::vec3 n, glm::vec2 uv) -> uint32_t {
        wowee::pipeline::WoweeModel::Vertex vtx;
        vtx.position = p; vtx.normal = n; vtx.texCoord = uv;
        wom.vertices.push_back(vtx);
        return static_cast<uint32_t>(wom.vertices.size() - 1);
    };
    auto addBox = [&](float cx, float cy, float cz,
                      float hx, float hy, float hz) {
        struct Face { glm::vec3 n, du, dv; };
        Face faces[6] = {
            {{0, 1, 0}, {1, 0, 0}, {0, 0, 1}},
            {{0,-1, 0}, {1, 0, 0}, {0, 0,-1}},
            {{1, 0, 0}, {0, 0, 1}, {0, 1, 0}},
            {{-1,0, 0}, {0, 0,-1}, {0, 1, 0}},
            {{0, 0, 1}, {-1,0, 0}, {0, 1, 0}},
            {{0, 0,-1}, {1, 0, 0}, {0, 1, 0}},
        };
        glm::vec3 c(cx, cy, cz);
        glm::vec3 ext(hx, hy, hz);
        for (const Face& f : faces) {
            glm::vec3 center = c + glm::vec3(f.n.x*hx, f.n.y*hy, f.n.z*hz);
            glm::vec3 du = glm::vec3(f.du.x*ext.x, f.du.y*ext.y, f.du.z*ext.z);
            glm::vec3 dv = glm::vec3(f.dv.x*ext.x, f.dv.y*ext.y, f.dv.z*ext.z);
            uint32_t base = static_cast<uint32_t>(wom.vertices.size());
            auto push = [&](glm::vec3 p, float u, float v) {
                wowee::pipeline::WoweeModel::Vertex vtx;
                vtx.position = p; vtx.normal = f.n; vtx.texCoord = {u, v};
                wom.vertices.push_back(vtx);
            };
            push(center - du - dv, 0, 0);
            push(center + du - dv, 1, 0);
            push(center + du + dv, 1, 1);
            push(center - du + dv, 0, 1);
            wom.indices.insert(wom.indices.end(),
                {base, base + 1, base + 2, base, base + 2, base + 3});
        }
    };
    // Base: low square slab, 10% of pillar height tall.
    float baseH = pillarH * 0.1f;
    float halfSize = size * 0.5f;
    addBox(0, baseH * 0.5f, 0, halfSize, baseH * 0.5f, halfSize);
    // 4 pillars at corners (inset by pillarR so they sit fully
    // on the base). Each is a 12-segment cylinder.
    const int segs = 12;
    float pillarOffset = halfSize - pillarR;
    auto addPillar = [&](float cx, float cz) {
        float y0 = baseH;
        float y1 = baseH + pillarH;
        uint32_t bot = static_cast<uint32_t>(wom.vertices.size());
        for (int sg = 0; sg <= segs; ++sg) {
            float u = static_cast<float>(sg) / segs;
            float ang = u * 2.0f * pi;
            glm::vec3 p(cx + pillarR * std::cos(ang), y0,
                        cz + pillarR * std::sin(ang));
            glm::vec3 n(std::cos(ang), 0, std::sin(ang));
            addV(p, n, {u, 0});
        }
        uint32_t top = static_cast<uint32_t>(wom.vertices.size());
        for (int sg = 0; sg <= segs; ++sg) {
            float u = static_cast<float>(sg) / segs;
            float ang = u * 2.0f * pi;
            glm::vec3 p(cx + pillarR * std::cos(ang), y1,
                        cz + pillarR * std::sin(ang));
            glm::vec3 n(std::cos(ang), 0, std::sin(ang));
            addV(p, n, {u, 1});
        }
        for (int sg = 0; sg < segs; ++sg) {
            wom.indices.insert(wom.indices.end(), {
                bot + sg, top + sg, bot + sg + 1,
                bot + sg + 1, top + sg, top + sg + 1
            });
        }
    };
    addPillar( pillarOffset,  pillarOffset);
    addPillar(-pillarOffset,  pillarOffset);
    addPillar( pillarOffset, -pillarOffset);
    addPillar(-pillarOffset, -pillarOffset);
    // Roof: flat slab on top of pillars, slightly larger than
    // the base so it overhangs the pillars.
    float roofY = baseH + pillarH;
    float roofHalfSize = halfSize * 1.05f;
    addBox(0, roofY + roofT * 0.5f, 0,
           roofHalfSize, roofT * 0.5f, roofHalfSize);
    wowee::pipeline::WoweeModel::Batch batch;
    batch.indexStart = 0;
    batch.indexCount = static_cast<uint32_t>(wom.indices.size());
    batch.textureIndex = 0;
    wom.batches.push_back(batch);
    float maxY = roofY + roofT;
    wom.boundMin = glm::vec3(-roofHalfSize, 0, -roofHalfSize);
    wom.boundMax = glm::vec3( roofHalfSize, maxY, roofHalfSize);
    if (!wowee::pipeline::WoweeModelLoader::save(wom, womBase)) {
        std::fprintf(stderr,
            "gen-mesh-shrine: failed to save %s.wom\n", womBase.c_str());
        return 1;
    }
    std::printf("Wrote %s.wom\n", womBase.c_str());
    std::printf("  size       : %.3f × %.3f\n", size, size);
    std::printf("  pillars    : 4 × R=%.3f H=%.3f\n", pillarR, pillarH);
    std::printf("  roof       : %.3f thick (%.3f overhang)\n",
                roofT, halfSize * 0.05f);
    std::printf("  total H    : %.3f\n", maxY);
    std::printf("  vertices   : %zu\n", wom.vertices.size());
    std::printf("  triangles  : %zu\n", wom.indices.size() / 3);
    return 0;
}

int handleTotem(int& i, int argc, char** argv) {
    // Tribal totem: stack of N square blocks alternating wide/
    // narrow widths so each carved face reads as distinct.
    // Even-indexed blocks are full width, odd are 70% — gives
    // the carved-segment look characteristic of totem poles.
    // The 35th procedural mesh primitive.
    std::string womBase = argv[++i];
    float baseW = 0.5f;        // base block half-width × 2
    int segments = 5;          // number of stacked blocks
    float segH = 0.5f;         // height of each block
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { baseW = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { segments = std::stoi(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { segH = std::stof(argv[++i]); } catch (...) {}
    }
    if (baseW <= 0 || segH <= 0 || segments < 1 || segments > 32) {
        std::fprintf(stderr,
            "gen-mesh-totem: dims > 0, segments 1..32\n");
        return 1;
    }
    if (womBase.size() >= 4 &&
        womBase.substr(womBase.size() - 4) == ".wom") {
        womBase = womBase.substr(0, womBase.size() - 4);
    }
    wowee::pipeline::WoweeModel wom;
    wom.name = std::filesystem::path(womBase).stem().string();
    wom.version = 3;
    auto addBox = [&](float cx, float cy, float cz,
                      float hx, float hy, float hz) {
        struct Face { glm::vec3 n, du, dv; };
        Face faces[6] = {
            {{0, 1, 0}, {1, 0, 0}, {0, 0, 1}},
            {{0,-1, 0}, {1, 0, 0}, {0, 0,-1}},
            {{1, 0, 0}, {0, 0, 1}, {0, 1, 0}},
            {{-1,0, 0}, {0, 0,-1}, {0, 1, 0}},
            {{0, 0, 1}, {-1,0, 0}, {0, 1, 0}},
            {{0, 0,-1}, {1, 0, 0}, {0, 1, 0}},
        };
        glm::vec3 c(cx, cy, cz);
        glm::vec3 ext(hx, hy, hz);
        for (const Face& f : faces) {
            glm::vec3 center = c + glm::vec3(f.n.x*hx, f.n.y*hy, f.n.z*hz);
            glm::vec3 du = glm::vec3(f.du.x*ext.x, f.du.y*ext.y, f.du.z*ext.z);
            glm::vec3 dv = glm::vec3(f.dv.x*ext.x, f.dv.y*ext.y, f.dv.z*ext.z);
            uint32_t base = static_cast<uint32_t>(wom.vertices.size());
            auto push = [&](glm::vec3 p, float u, float v) {
                wowee::pipeline::WoweeModel::Vertex vtx;
                vtx.position = p; vtx.normal = f.n; vtx.texCoord = {u, v};
                wom.vertices.push_back(vtx);
            };
            push(center - du - dv, 0, 0);
            push(center + du - dv, 1, 0);
            push(center + du + dv, 1, 1);
            push(center - du + dv, 0, 1);
            wom.indices.insert(wom.indices.end(),
                {base, base + 1, base + 2, base, base + 2, base + 3});
        }
    };
    // Stack blocks bottom-up. Bottom block always full width.
    // Even blocks (0, 2, 4...) get full width, odd blocks 70%.
    for (int s = 0; s < segments; ++s) {
        float cy = (s + 0.5f) * segH;
        float halfW = (s & 1) ? (baseW * 0.5f * 0.70f) : (baseW * 0.5f);
        addBox(0, cy, 0, halfW, segH * 0.5f, halfW);
    }
    wowee::pipeline::WoweeModel::Batch batch;
    batch.indexStart = 0;
    batch.indexCount = static_cast<uint32_t>(wom.indices.size());
    batch.textureIndex = 0;
    wom.batches.push_back(batch);
    float maxY = segments * segH;
    float maxXZ = baseW * 0.5f;
    wom.boundMin = glm::vec3(-maxXZ, 0, -maxXZ);
    wom.boundMax = glm::vec3( maxXZ, maxY, maxXZ);
    if (!wowee::pipeline::WoweeModelLoader::save(wom, womBase)) {
        std::fprintf(stderr,
            "gen-mesh-totem: failed to save %s.wom\n", womBase.c_str());
        return 1;
    }
    std::printf("Wrote %s.wom\n", womBase.c_str());
    std::printf("  base width : %.3f\n", baseW);
    std::printf("  segments   : %d (each %.3f tall)\n", segments, segH);
    std::printf("  total H    : %.3f\n", maxY);
    std::printf("  vertices   : %zu\n", wom.vertices.size());
    std::printf("  triangles  : %zu\n", wom.indices.size() / 3);
    return 0;
}

int handleCage(int& i, int argc, char** argv) {
    // Square cage: top + bottom thin frame slabs + 4 corner
    // posts + N evenly spaced bars on each of the 4 sides.
    // Bars are thin square cross-section so they read as
    // metal rods. Useful for prison cells, animal pens,
    // dungeon set dressing.
    std::string womBase = argv[++i];
    float width = 1.5f;        // along X = Z (square footprint)
    float height = 2.0f;
    int barsPerSide = 5;
    float barRadius = 0.04f;
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { width = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { height = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { barsPerSide = std::stoi(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { barRadius = std::stof(argv[++i]); } catch (...) {}
    }
    if (width <= 0 || height <= 0 || barRadius <= 0 ||
        barsPerSide < 0 || barsPerSide > 64) {
        std::fprintf(stderr,
            "gen-mesh-cage: dims > 0, barsPerSide 0..64\n");
        return 1;
    }
    if (womBase.size() >= 4 &&
        womBase.substr(womBase.size() - 4) == ".wom") {
        womBase = womBase.substr(0, womBase.size() - 4);
    }
    wowee::pipeline::WoweeModel wom;
    wom.name = std::filesystem::path(womBase).stem().string();
    wom.version = 3;
    auto addBox = [&](float cx, float cy, float cz,
                      float hx, float hy, float hz) {
        struct Face { glm::vec3 n, du, dv; };
        Face faces[6] = {
            {{0, 1, 0}, {1, 0, 0}, {0, 0, 1}},
            {{0,-1, 0}, {1, 0, 0}, {0, 0,-1}},
            {{1, 0, 0}, {0, 0, 1}, {0, 1, 0}},
            {{-1,0, 0}, {0, 0,-1}, {0, 1, 0}},
            {{0, 0, 1}, {-1,0, 0}, {0, 1, 0}},
            {{0, 0,-1}, {1, 0, 0}, {0, 1, 0}},
        };
        glm::vec3 c(cx, cy, cz);
        glm::vec3 ext(hx, hy, hz);
        for (const Face& f : faces) {
            glm::vec3 center = c + glm::vec3(f.n.x*hx, f.n.y*hy, f.n.z*hz);
            glm::vec3 du = glm::vec3(f.du.x*ext.x, f.du.y*ext.y, f.du.z*ext.z);
            glm::vec3 dv = glm::vec3(f.dv.x*ext.x, f.dv.y*ext.y, f.dv.z*ext.z);
            uint32_t base = static_cast<uint32_t>(wom.vertices.size());
            auto push = [&](glm::vec3 p, float u, float v) {
                wowee::pipeline::WoweeModel::Vertex vtx;
                vtx.position = p; vtx.normal = f.n; vtx.texCoord = {u, v};
                wom.vertices.push_back(vtx);
            };
            push(center - du - dv, 0, 0);
            push(center + du - dv, 1, 0);
            push(center + du + dv, 1, 1);
            push(center - du + dv, 0, 1);
            wom.indices.insert(wom.indices.end(),
                {base, base + 1, base + 2, base, base + 2, base + 3});
        }
    };
    float halfW = width * 0.5f;
    float frameT = barRadius * 1.5f;  // top/bottom slab thickness
    // Top + bottom frame slabs
    addBox(0, frameT * 0.5f, 0, halfW, frameT * 0.5f, halfW);
    addBox(0, height - frameT * 0.5f, 0, halfW, frameT * 0.5f, halfW);
    // 4 corner posts (thicker than bars)
    float postR = barRadius * 1.5f;
    float postCY = height * 0.5f;
    float postHy = height * 0.5f;
    float corner = halfW - postR;
    addBox( corner, postCY,  corner, postR, postHy, postR);
    addBox(-corner, postCY,  corner, postR, postHy, postR);
    addBox( corner, postCY, -corner, postR, postHy, postR);
    addBox(-corner, postCY, -corner, postR, postHy, postR);
    // Bars: N bars per side, evenly distributed between corners.
    // Side spans from -corner to +corner; bars at (k+1)/(N+1)
    // along the span so they're inset (no overlap with corners).
    float barCY = height * 0.5f;
    float barHy = (height - 2 * frameT) * 0.5f;
    float barCYadj = frameT + barHy;
    int barTotal = 0;
    for (int k = 0; k < barsPerSide; ++k) {
        float t = (k + 1.0f) / (barsPerSide + 1.0f);
        float pos = -corner + t * 2.0f * corner;  // from -corner to +corner
        // +Z and -Z sides (bars span X)
        addBox(pos, barCYadj,  halfW - barRadius,
               barRadius, barHy, barRadius);
        addBox(pos, barCYadj, -halfW + barRadius,
               barRadius, barHy, barRadius);
        // +X and -X sides (bars span Z)
        addBox( halfW - barRadius, barCYadj, pos,
               barRadius, barHy, barRadius);
        addBox(-halfW + barRadius, barCYadj, pos,
               barRadius, barHy, barRadius);
        barTotal += 4;
    }
    wowee::pipeline::WoweeModel::Batch batch;
    batch.indexStart = 0;
    batch.indexCount = static_cast<uint32_t>(wom.indices.size());
    batch.textureIndex = 0;
    wom.batches.push_back(batch);
    wom.boundMin = glm::vec3(-halfW, 0, -halfW);
    wom.boundMax = glm::vec3( halfW, height, halfW);
    if (!wowee::pipeline::WoweeModelLoader::save(wom, womBase)) {
        std::fprintf(stderr,
            "gen-mesh-cage: failed to save %s.wom\n", womBase.c_str());
        return 1;
    }
    std::printf("Wrote %s.wom\n", womBase.c_str());
    std::printf("  width × height : %.3f × %.3f\n", width, height);
    std::printf("  bars per side  : %d (%d total)\n",
                barsPerSide, barTotal);
    std::printf("  bar radius     : %.3f\n", barRadius);
    std::printf("  vertices       : %zu\n", wom.vertices.size());
    std::printf("  triangles      : %zu\n", wom.indices.size() / 3);
    return 0;
}

int handleThrone(int& i, int argc, char** argv) {
    // Throne: pedestal slab + seat block + tall backrest +
    // 2 armrests on either side. Reads as a regal seat from
    // any angle. The 37th procedural mesh primitive.
    std::string womBase = argv[++i];
    float seatW = 0.8f;        // along X
    float seatH = 0.5f;        // top of seat above pedestal
    float backH = 1.5f;        // backrest extends this above seat
    float pedSize = 1.2f;      // pedestal width = depth
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { seatW = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { seatH = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { backH = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { pedSize = std::stof(argv[++i]); } catch (...) {}
    }
    if (seatW <= 0 || seatH <= 0 || backH <= 0 || pedSize <= 0 ||
        pedSize < seatW) {
        std::fprintf(stderr,
            "gen-mesh-throne: dims > 0; pedSize must be >= seatW\n");
        return 1;
    }
    if (womBase.size() >= 4 &&
        womBase.substr(womBase.size() - 4) == ".wom") {
        womBase = womBase.substr(0, womBase.size() - 4);
    }
    wowee::pipeline::WoweeModel wom;
    wom.name = std::filesystem::path(womBase).stem().string();
    wom.version = 3;
    auto addBox = [&](float cx, float cy, float cz,
                      float hx, float hy, float hz) {
        struct Face { glm::vec3 n, du, dv; };
        Face faces[6] = {
            {{0, 1, 0}, {1, 0, 0}, {0, 0, 1}},
            {{0,-1, 0}, {1, 0, 0}, {0, 0,-1}},
            {{1, 0, 0}, {0, 0, 1}, {0, 1, 0}},
            {{-1,0, 0}, {0, 0,-1}, {0, 1, 0}},
            {{0, 0, 1}, {-1,0, 0}, {0, 1, 0}},
            {{0, 0,-1}, {1, 0, 0}, {0, 1, 0}},
        };
        glm::vec3 c(cx, cy, cz);
        glm::vec3 ext(hx, hy, hz);
        for (const Face& f : faces) {
            glm::vec3 center = c + glm::vec3(f.n.x*hx, f.n.y*hy, f.n.z*hz);
            glm::vec3 du = glm::vec3(f.du.x*ext.x, f.du.y*ext.y, f.du.z*ext.z);
            glm::vec3 dv = glm::vec3(f.dv.x*ext.x, f.dv.y*ext.y, f.dv.z*ext.z);
            uint32_t base = static_cast<uint32_t>(wom.vertices.size());
            auto push = [&](glm::vec3 p, float u, float v) {
                wowee::pipeline::WoweeModel::Vertex vtx;
                vtx.position = p; vtx.normal = f.n; vtx.texCoord = {u, v};
                wom.vertices.push_back(vtx);
            };
            push(center - du - dv, 0, 0);
            push(center + du - dv, 1, 0);
            push(center + du + dv, 1, 1);
            push(center - du + dv, 0, 1);
            wom.indices.insert(wom.indices.end(),
                {base, base + 1, base + 2, base, base + 2, base + 3});
        }
    };
    // Pedestal: low square slab at the floor
    float pedH = seatH * 0.4f;
    float halfPed = pedSize * 0.5f;
    addBox(0, pedH * 0.5f, 0, halfPed, pedH * 0.5f, halfPed);
    // Seat: thick square cushion sitting on pedestal
    float seatT = seatH * 0.3f;       // seat thickness (along Y)
    float seatCY = pedH + seatT * 0.5f;
    float halfSeat = seatW * 0.5f;
    addBox(0, seatCY, 0, halfSeat, seatT * 0.5f, halfSeat);
    // Backrest: tall vertical slab at -Z edge of seat, slim in Z
    float backT = seatT * 0.6f;
    float backCY = pedH + seatT + backH * 0.5f;
    addBox(0, backCY, -halfSeat + backT * 0.5f,
           halfSeat, backH * 0.5f, backT * 0.5f);
    // Armrests: 2 small blocks on the sides
    float armW = backT * 0.8f;
    float armH = seatH * 0.4f;
    float armCY = pedH + seatT + armH * 0.5f;
    float armDepth = halfSeat * 0.7f;
    addBox( halfSeat - armW * 0.5f, armCY, 0,
           armW * 0.5f, armH * 0.5f, armDepth);
    addBox(-halfSeat + armW * 0.5f, armCY, 0,
           armW * 0.5f, armH * 0.5f, armDepth);
    wowee::pipeline::WoweeModel::Batch batch;
    batch.indexStart = 0;
    batch.indexCount = static_cast<uint32_t>(wom.indices.size());
    batch.textureIndex = 0;
    wom.batches.push_back(batch);
    float maxY = pedH + seatT + backH;
    wom.boundMin = glm::vec3(-halfPed, 0, -halfPed);
    wom.boundMax = glm::vec3( halfPed, maxY, halfPed);
    if (!wowee::pipeline::WoweeModelLoader::save(wom, womBase)) {
        std::fprintf(stderr,
            "gen-mesh-throne: failed to save %s.wom\n", womBase.c_str());
        return 1;
    }
    std::printf("Wrote %s.wom\n", womBase.c_str());
    std::printf("  pedestal   : %.3f × %.3f (h=%.3f)\n",
                pedSize, pedSize, pedH);
    std::printf("  seat       : %.3f × %.3f\n", seatW, seatT);
    std::printf("  backrest   : H=%.3f\n", backH);
    std::printf("  total H    : %.3f\n", maxY);
    std::printf("  vertices   : %zu\n", wom.vertices.size());
    std::printf("  triangles  : %zu\n", wom.indices.size() / 3);
    return 0;
}

int handleCoffin(int& i, int argc, char** argv) {
    // Coffin: classic 6-sided "hexagonal" prism with the
    // characteristic narrow-head / wide-shoulder / tapered-foot
    // top-down profile that reads as a coffin from any angle.
    // Six side faces + top lid + bottom panel — face-shared
    // normals via separate vertex sets per face. The 38th
    // procedural mesh primitive — useful for graveyard set
    // dressing alongside --gen-mesh-grave.
    std::string womBase = argv[++i];
    float length = 2.0f;     // along Z
    float width  = 0.8f;     // shoulder width along X
    float height = 0.6f;     // along Y
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { length = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { width = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { height = std::stof(argv[++i]); } catch (...) {}
    }
    if (length <= 0 || width <= 0 || height <= 0) {
        std::fprintf(stderr,
            "gen-mesh-coffin: length/width/height must be > 0\n");
        return 1;
    }
    if (womBase.size() >= 4 &&
        womBase.substr(womBase.size() - 4) == ".wom") {
        womBase = womBase.substr(0, womBase.size() - 4);
    }
    wowee::pipeline::WoweeModel wom;
    wom.name = std::filesystem::path(womBase).stem().string();
    wom.version = 3;
    // Top-down hexagonal coffin profile (CCW from head looking
    // down +Y). Head end is narrow, shoulder is widest, feet
    // taper to a narrow toe — the canonical "casket" silhouette.
    float hL = length * 0.5f;
    float hW = width * 0.5f;
    glm::vec2 ring[6] = {
        { 0.0f,         hL          },  // p0 head tip
        {-hW,           hL * 0.6f   },  // p1 left shoulder (widest)
        {-hW * 0.8f,   -hL * 0.6f   },  // p2 left hip
        { 0.0f,        -hL          },  // p3 foot tip
        { hW * 0.8f,   -hL * 0.6f   },  // p4 right hip
        { hW,           hL * 0.6f   },  // p5 right shoulder
    };
    auto addQuad = [&](glm::vec3 a, glm::vec3 b, glm::vec3 c, glm::vec3 d,
                       glm::vec3 n) {
        uint32_t base = static_cast<uint32_t>(wom.vertices.size());
        auto push = [&](glm::vec3 p, float u, float v) {
            wowee::pipeline::WoweeModel::Vertex vtx;
            vtx.position = p; vtx.normal = n; vtx.texCoord = {u, v};
            wom.vertices.push_back(vtx);
        };
        push(a, 0, 0);
        push(b, 1, 0);
        push(c, 1, 1);
        push(d, 0, 1);
        wom.indices.insert(wom.indices.end(),
            {base, base + 1, base + 2, base, base + 2, base + 3});
    };
    // Six side faces — each a quad from bottom-edge to top-edge
    // of one segment of the hexagon. Normal is the outward
    // perpendicular to the side edge in the XZ plane.
    for (int s = 0; s < 6; ++s) {
        const glm::vec2& a = ring[s];
        const glm::vec2& b = ring[(s + 1) % 6];
        glm::vec3 bot0(a.x, 0.0f,    a.y);
        glm::vec3 bot1(b.x, 0.0f,    b.y);
        glm::vec3 top1(b.x, height,  b.y);
        glm::vec3 top0(a.x, height,  a.y);
        // Outward normal: 90° CW rotation of edge vector in XZ
        // (since vertices wind CCW looking down, outward is +X
        // when edge goes -Z, i.e. swap & negate one component).
        glm::vec2 edge = b - a;
        glm::vec3 n(edge.y, 0.0f, -edge.x);
        n = glm::normalize(n);
        addQuad(bot0, bot1, top1, top0, n);
    }
    // Top lid: fan of 4 triangles from p0, all sharing +Y normal.
    {
        glm::vec3 normal(0.0f, 1.0f, 0.0f);
        uint32_t base = static_cast<uint32_t>(wom.vertices.size());
        for (int v = 0; v < 6; ++v) {
            wowee::pipeline::WoweeModel::Vertex vtx;
            vtx.position = glm::vec3(ring[v].x, height, ring[v].y);
            vtx.normal = normal;
            // Cheap planar UV from top-down ring coords.
            vtx.texCoord = { ring[v].x / width  + 0.5f,
                             ring[v].y / length + 0.5f };
            wom.vertices.push_back(vtx);
        }
        for (int t = 1; t < 5; ++t) {
            wom.indices.insert(wom.indices.end(),
                {base, base + static_cast<uint32_t>(t),
                 base + static_cast<uint32_t>(t + 1)});
        }
    }
    // Bottom panel: same fan but reversed winding for -Y normal.
    {
        glm::vec3 normal(0.0f, -1.0f, 0.0f);
        uint32_t base = static_cast<uint32_t>(wom.vertices.size());
        for (int v = 0; v < 6; ++v) {
            wowee::pipeline::WoweeModel::Vertex vtx;
            vtx.position = glm::vec3(ring[v].x, 0.0f, ring[v].y);
            vtx.normal = normal;
            vtx.texCoord = { ring[v].x / width  + 0.5f,
                             ring[v].y / length + 0.5f };
            wom.vertices.push_back(vtx);
        }
        for (int t = 1; t < 5; ++t) {
            wom.indices.insert(wom.indices.end(),
                {base, base + static_cast<uint32_t>(t + 1),
                 base + static_cast<uint32_t>(t)});
        }
    }
    wowee::pipeline::WoweeModel::Batch batch;
    batch.indexStart = 0;
    batch.indexCount = static_cast<uint32_t>(wom.indices.size());
    batch.textureIndex = 0;
    wom.batches.push_back(batch);
    wom.boundMin = glm::vec3(-hW, 0.0f,    -hL);
    wom.boundMax = glm::vec3( hW, height,   hL);
    if (!wowee::pipeline::WoweeModelLoader::save(wom, womBase)) {
        std::fprintf(stderr,
            "gen-mesh-coffin: failed to save %s.wom\n", womBase.c_str());
        return 1;
    }
    std::printf("Wrote %s.wom\n", womBase.c_str());
    std::printf("  length     : %.3f\n", length);
    std::printf("  width      : %.3f (shoulder)\n", width);
    std::printf("  height     : %.3f\n", height);
    std::printf("  vertices   : %zu\n", wom.vertices.size());
    std::printf("  triangles  : %zu\n", wom.indices.size() / 3);
    return 0;
}

int handleBed(int& i, int argc, char** argv) {
    // Bed: 7-box bedroom prop — flat mattress slab, tall
    // headboard at one end, short shorter footboard at the
    // other, 4 corner legs, and a small pillow box at the
    // headboard end. Pairs with --gen-mesh-table /
    // --gen-mesh-bookshelf for inn rooms, manor bedrooms,
    // barracks. The 42nd procedural mesh primitive.
    std::string womBase = argv[++i];
    float length    = 2.0f;     // along Z (head-to-foot)
    float width     = 1.2f;     // along X
    float legHeight = 0.30f;
    float matThick  = 0.20f;
    float headH     = 1.0f;     // headboard height above mattress
    float footH     = 0.4f;     // footboard height above mattress
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { length = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { width = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { legHeight = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { matThick = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { headH = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { footH = std::stof(argv[++i]); } catch (...) {}
    }
    if (length <= 0 || width <= 0 || legHeight <= 0 ||
        matThick <= 0 || headH <= 0 || footH <= 0) {
        std::fprintf(stderr, "gen-mesh-bed: all dims must be > 0\n");
        return 1;
    }
    if (womBase.size() >= 4 &&
        womBase.substr(womBase.size() - 4) == ".wom") {
        womBase = womBase.substr(0, womBase.size() - 4);
    }
    wowee::pipeline::WoweeModel wom;
    wom.name = std::filesystem::path(womBase).stem().string();
    wom.version = 3;
    auto addBox = [&](float cx, float cy, float cz,
                      float hx, float hy, float hz) {
        struct Face { glm::vec3 n, du, dv; };
        Face faces[6] = {
            {{0, 1, 0}, {1, 0, 0}, {0, 0, 1}},
            {{0,-1, 0}, {1, 0, 0}, {0, 0,-1}},
            {{1, 0, 0}, {0, 0, 1}, {0, 1, 0}},
            {{-1,0, 0}, {0, 0,-1}, {0, 1, 0}},
            {{0, 0, 1}, {-1,0, 0}, {0, 1, 0}},
            {{0, 0,-1}, {1, 0, 0}, {0, 1, 0}},
        };
        glm::vec3 c(cx, cy, cz);
        for (const Face& f : faces) {
            glm::vec3 center = c + glm::vec3(f.n.x*hx, f.n.y*hy, f.n.z*hz);
            glm::vec3 du = glm::vec3(f.du.x*hx, f.du.y*hy, f.du.z*hz);
            glm::vec3 dv = glm::vec3(f.dv.x*hx, f.dv.y*hy, f.dv.z*hz);
            uint32_t base = static_cast<uint32_t>(wom.vertices.size());
            auto push = [&](glm::vec3 p, float u, float v) {
                wowee::pipeline::WoweeModel::Vertex vtx;
                vtx.position = p; vtx.normal = f.n; vtx.texCoord = {u, v};
                wom.vertices.push_back(vtx);
            };
            push(center - du - dv, 0, 0);
            push(center + du - dv, 1, 0);
            push(center + du + dv, 1, 1);
            push(center - du + dv, 0, 1);
            wom.indices.insert(wom.indices.end(),
                {base, base + 1, base + 2, base, base + 2, base + 3});
        }
    };
    float halfL = length * 0.5f;
    float halfW = width  * 0.5f;
    float legT  = std::min(width, length) * 0.06f;  // square cross-section
    float halfLeg = legT * 0.5f;
    // Head end is at +Z, foot end at -Z.
    // 4 legs: one per corner, inset from edges by half a leg-thickness.
    float legX = halfW - halfLeg;
    float legZ = halfL - halfLeg;
    float legCY = legHeight * 0.5f;
    addBox( legX, legCY,  legZ, halfLeg, legHeight * 0.5f, halfLeg);
    addBox(-legX, legCY,  legZ, halfLeg, legHeight * 0.5f, halfLeg);
    addBox( legX, legCY, -legZ, halfLeg, legHeight * 0.5f, halfLeg);
    addBox(-legX, legCY, -legZ, halfLeg, legHeight * 0.5f, halfLeg);
    // Mattress: spans full width × length, sits on top of legs.
    float matBottomY = legHeight;
    float matCY = matBottomY + matThick * 0.5f;
    addBox(0, matCY, 0, halfW, matThick * 0.5f, halfL);
    // Headboard: tall thin slab at +Z end, spanning full width.
    // Sits on top of the mattress base (its bottom is at matBottomY).
    float headThick = legT * 1.4f;
    float headCY = matBottomY + headH * 0.5f;
    addBox(0, headCY, halfL - headThick * 0.5f,
           halfW, headH * 0.5f, headThick * 0.5f);
    // Footboard: shorter slab at -Z end.
    float footCY = matBottomY + footH * 0.5f;
    addBox(0, footCY, -halfL + headThick * 0.5f,
           halfW, footH * 0.5f, headThick * 0.5f);
    // Pillow: small box on the mattress, near the headboard end.
    float pillowW    = halfW * 1.6f;     // 80% of mattress width
    float pillowL    = halfL * 0.25f;    // ~12.5% of mattress length
    float pillowH    = matThick * 0.5f;
    float pillowCY   = matBottomY + matThick + pillowH * 0.5f;
    float pillowZ    = halfL - pillowL - headThick;
    addBox(0, pillowCY, pillowZ,
           pillowW * 0.5f, pillowH * 0.5f, pillowL * 0.5f);
    wowee::pipeline::WoweeModel::Batch batch;
    batch.indexStart = 0;
    batch.indexCount = static_cast<uint32_t>(wom.indices.size());
    batch.textureIndex = 0;
    wom.batches.push_back(batch);
    float totalH = matBottomY + std::max({matThick + pillowH, headH, footH});
    wom.boundMin = glm::vec3(-halfW, 0.0f,    -halfL);
    wom.boundMax = glm::vec3( halfW, totalH,   halfL);
    if (!wowee::pipeline::WoweeModelLoader::save(wom, womBase)) {
        std::fprintf(stderr,
            "gen-mesh-bed: failed to save %s.wom\n", womBase.c_str());
        return 1;
    }
    std::printf("Wrote %s.wom\n", womBase.c_str());
    std::printf("  size       : %.3f x %.3f x %.3f (W x H x L)\n",
                width, totalH, length);
    std::printf("  mattress   : %.3f thick at y=%.3f\n",
                matThick, matBottomY);
    std::printf("  headboard  : %.3f tall (foot %.3f tall)\n",
                headH, footH);
    std::printf("  vertices   : %zu\n", wom.vertices.size());
    std::printf("  triangles  : %zu\n", wom.indices.size() / 3);
    return 0;
}

int handleLamppost(int& i, int argc, char** argv) {
    // Lamppost: 4-box urban prop — square base plinth, tall
    // vertical pole, lantern body box around the pole top,
    // and a small cap box on top. Useful for streets, plazas,
    // taverns, anywhere that wants explicit lighting fixtures.
    // The 41st procedural mesh primitive.
    std::string womBase = argv[++i];
    float postHeight    = 3.0f;
    float postThickness = 0.12f;
    float baseSize      = 0.4f;
    float lanternSize   = 0.35f;
    float lanternHeight = 0.5f;
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { postHeight = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { postThickness = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { baseSize = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { lanternSize = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { lanternHeight = std::stof(argv[++i]); } catch (...) {}
    }
    if (postHeight <= 0 || postThickness <= 0 || baseSize <= 0 ||
        lanternSize <= 0 || lanternHeight <= 0 ||
        postThickness >= baseSize || postThickness >= lanternSize) {
        std::fprintf(stderr,
            "gen-mesh-lamppost: dims > 0; post must fit in base & lantern\n");
        return 1;
    }
    if (womBase.size() >= 4 &&
        womBase.substr(womBase.size() - 4) == ".wom") {
        womBase = womBase.substr(0, womBase.size() - 4);
    }
    wowee::pipeline::WoweeModel wom;
    wom.name = std::filesystem::path(womBase).stem().string();
    wom.version = 3;
    auto addBox = [&](float cx, float cy, float cz,
                      float hx, float hy, float hz) {
        struct Face { glm::vec3 n, du, dv; };
        Face faces[6] = {
            {{0, 1, 0}, {1, 0, 0}, {0, 0, 1}},
            {{0,-1, 0}, {1, 0, 0}, {0, 0,-1}},
            {{1, 0, 0}, {0, 0, 1}, {0, 1, 0}},
            {{-1,0, 0}, {0, 0,-1}, {0, 1, 0}},
            {{0, 0, 1}, {-1,0, 0}, {0, 1, 0}},
            {{0, 0,-1}, {1, 0, 0}, {0, 1, 0}},
        };
        glm::vec3 c(cx, cy, cz);
        for (const Face& f : faces) {
            glm::vec3 center = c + glm::vec3(f.n.x*hx, f.n.y*hy, f.n.z*hz);
            glm::vec3 du = glm::vec3(f.du.x*hx, f.du.y*hy, f.du.z*hz);
            glm::vec3 dv = glm::vec3(f.dv.x*hx, f.dv.y*hy, f.dv.z*hz);
            uint32_t base = static_cast<uint32_t>(wom.vertices.size());
            auto push = [&](glm::vec3 p, float u, float v) {
                wowee::pipeline::WoweeModel::Vertex vtx;
                vtx.position = p; vtx.normal = f.n; vtx.texCoord = {u, v};
                wom.vertices.push_back(vtx);
            };
            push(center - du - dv, 0, 0);
            push(center + du - dv, 1, 0);
            push(center + du + dv, 1, 1);
            push(center - du + dv, 0, 1);
            wom.indices.insert(wom.indices.end(),
                {base, base + 1, base + 2, base, base + 2, base + 3});
        }
    };
    // Base plinth: low square slab at the floor.
    float baseHeight = baseSize * 0.4f;
    float halfBase = baseSize * 0.5f;
    addBox(0, baseHeight * 0.5f, 0,
           halfBase, baseHeight * 0.5f, halfBase);
    // Vertical pole: thin square box from top of base to top.
    float poleBottomY = baseHeight;
    float poleTopY    = baseHeight + postHeight;
    float poleCY      = (poleBottomY + poleTopY) * 0.5f;
    float halfPole    = postThickness * 0.5f;
    addBox(0, poleCY, 0,
           halfPole, postHeight * 0.5f, halfPole);
    // Lantern body: box centred on the top of the pole; bottom
    // of the box overlaps the pole so the lamp visually 'caps'
    // the pole rather than just floating above it.
    float halfLantern = lanternSize * 0.5f;
    float lanternBottomY = poleTopY - lanternHeight * 0.3f;
    float lanternCY = lanternBottomY + lanternHeight * 0.5f;
    addBox(0, lanternCY, 0,
           halfLantern, lanternHeight * 0.5f, halfLantern);
    // Cap: thin square plate on top of the lantern. Slightly
    // wider than the lantern body so the cap reads as an awning.
    float capH    = lanternHeight * 0.18f;
    float capSize = lanternSize * 1.15f;
    float halfCap = capSize * 0.5f;
    float capCY   = lanternBottomY + lanternHeight + capH * 0.5f;
    addBox(0, capCY, 0,
           halfCap, capH * 0.5f, halfCap);
    wowee::pipeline::WoweeModel::Batch batch;
    batch.indexStart = 0;
    batch.indexCount = static_cast<uint32_t>(wom.indices.size());
    batch.textureIndex = 0;
    wom.batches.push_back(batch);
    float totalH = capCY + capH * 0.5f;
    wom.boundMin = glm::vec3(-halfBase, 0.0f,    -halfBase);
    wom.boundMax = glm::vec3( halfBase, totalH,   halfBase);
    if (!wowee::pipeline::WoweeModelLoader::save(wom, womBase)) {
        std::fprintf(stderr,
            "gen-mesh-lamppost: failed to save %s.wom\n", womBase.c_str());
        return 1;
    }
    std::printf("Wrote %s.wom\n", womBase.c_str());
    std::printf("  total H    : %.3f\n", totalH);
    std::printf("  base       : %.3f square × %.3f tall\n",
                baseSize, baseHeight);
    std::printf("  pole       : %.3f square × %.3f tall\n",
                postThickness, postHeight);
    std::printf("  lantern    : %.3f square × %.3f tall (with cap)\n",
                lanternSize, lanternHeight);
    std::printf("  vertices   : %zu\n", wom.vertices.size());
    std::printf("  triangles  : %zu\n", wom.indices.size() / 3);
    return 0;
}

int handleTable(int& i, int argc, char** argv) {
    // Table: 5 boxes — flat tabletop slab on top of 4 vertical
    // legs at each corner. Thinnest of the furniture meshes,
    // pairs naturally with --gen-mesh-bench / --gen-mesh-throne
    // for taverns and dining halls. The 40th procedural mesh
    // primitive.
    std::string womBase = argv[++i];
    float width  = 1.6f;     // along X
    float depth  = 1.0f;     // along Z
    float height = 0.85f;    // along Y (top of tabletop)
    float legT   = 0.10f;    // leg thickness (square cross-section)
    float topT   = 0.06f;    // tabletop thickness
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { width = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { depth = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { height = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { legT = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { topT = std::stof(argv[++i]); } catch (...) {}
    }
    if (width <= 0 || depth <= 0 || height <= 0 || legT <= 0 ||
        topT <= 0 || legT * 2 > width || legT * 2 > depth ||
        topT >= height) {
        std::fprintf(stderr,
            "gen-mesh-table: dims > 0; legT must fit in width/depth; topT < height\n");
        return 1;
    }
    if (womBase.size() >= 4 &&
        womBase.substr(womBase.size() - 4) == ".wom") {
        womBase = womBase.substr(0, womBase.size() - 4);
    }
    wowee::pipeline::WoweeModel wom;
    wom.name = std::filesystem::path(womBase).stem().string();
    wom.version = 3;
    auto addBox = [&](float cx, float cy, float cz,
                      float hx, float hy, float hz) {
        struct Face { glm::vec3 n, du, dv; };
        Face faces[6] = {
            {{0, 1, 0}, {1, 0, 0}, {0, 0, 1}},
            {{0,-1, 0}, {1, 0, 0}, {0, 0,-1}},
            {{1, 0, 0}, {0, 0, 1}, {0, 1, 0}},
            {{-1,0, 0}, {0, 0,-1}, {0, 1, 0}},
            {{0, 0, 1}, {-1,0, 0}, {0, 1, 0}},
            {{0, 0,-1}, {1, 0, 0}, {0, 1, 0}},
        };
        glm::vec3 c(cx, cy, cz);
        for (const Face& f : faces) {
            glm::vec3 center = c + glm::vec3(f.n.x*hx, f.n.y*hy, f.n.z*hz);
            glm::vec3 du = glm::vec3(f.du.x*hx, f.du.y*hy, f.du.z*hz);
            glm::vec3 dv = glm::vec3(f.dv.x*hx, f.dv.y*hy, f.dv.z*hz);
            uint32_t base = static_cast<uint32_t>(wom.vertices.size());
            auto push = [&](glm::vec3 p, float u, float v) {
                wowee::pipeline::WoweeModel::Vertex vtx;
                vtx.position = p; vtx.normal = f.n; vtx.texCoord = {u, v};
                wom.vertices.push_back(vtx);
            };
            push(center - du - dv, 0, 0);
            push(center + du - dv, 1, 0);
            push(center + du + dv, 1, 1);
            push(center - du + dv, 0, 1);
            wom.indices.insert(wom.indices.end(),
                {base, base + 1, base + 2, base, base + 2, base + 3});
        }
    };
    float halfW = width  * 0.5f;
    float halfD = depth  * 0.5f;
    float halfLeg = legT * 0.5f;
    float legHeight = height - topT;
    // Tabletop: spans full width × depth, sits at y=height-topT to y=height.
    addBox(0, height - topT * 0.5f, 0,
           halfW, topT * 0.5f, halfD);
    // 4 legs: one at each corner, inset by legT/2 from the edge.
    float legCY = legHeight * 0.5f;
    float legX  = halfW - halfLeg;
    float legZ  = halfD - halfLeg;
    addBox( legX, legCY,  legZ, halfLeg, legHeight * 0.5f, halfLeg);
    addBox(-legX, legCY,  legZ, halfLeg, legHeight * 0.5f, halfLeg);
    addBox( legX, legCY, -legZ, halfLeg, legHeight * 0.5f, halfLeg);
    addBox(-legX, legCY, -legZ, halfLeg, legHeight * 0.5f, halfLeg);
    wowee::pipeline::WoweeModel::Batch batch;
    batch.indexStart = 0;
    batch.indexCount = static_cast<uint32_t>(wom.indices.size());
    batch.textureIndex = 0;
    wom.batches.push_back(batch);
    wom.boundMin = glm::vec3(-halfW, 0.0f,    -halfD);
    wom.boundMax = glm::vec3( halfW, height,   halfD);
    if (!wowee::pipeline::WoweeModelLoader::save(wom, womBase)) {
        std::fprintf(stderr,
            "gen-mesh-table: failed to save %s.wom\n", womBase.c_str());
        return 1;
    }
    std::printf("Wrote %s.wom\n", womBase.c_str());
    std::printf("  size       : %.3f x %.3f x %.3f\n", width, height, depth);
    std::printf("  legs       : 4 × %.3f square (%.3f tall)\n",
                legT, legHeight);
    std::printf("  top thick  : %.3f\n", topT);
    std::printf("  vertices   : %zu\n", wom.vertices.size());
    std::printf("  triangles  : %zu\n", wom.indices.size() / 3);
    return 0;
}

int handleBookshelf(int& i, int argc, char** argv) {
    // Bookshelf: cabinet (5 panels: back / left / right / top /
    // bottom) divided by N-1 horizontal shelves, with rows of
    // thin "book" boxes at varying heights on each shelf.
    // Books sway in width and height pseudo-randomly so the
    // shelf doesn't read as a perfect grid. The 39th procedural
    // mesh primitive.
    std::string womBase = argv[++i];
    float width  = 1.5f;
    float height = 2.0f;
    float depth  = 0.4f;
    int shelves  = 4;
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { width = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { height = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { depth = std::stof(argv[++i]); } catch (...) {}
    }
    if (i + 1 < argc && argv[i + 1][0] != '-') {
        try { shelves = std::stoi(argv[++i]); } catch (...) {}
    }
    if (width <= 0 || height <= 0 || depth <= 0 ||
        shelves < 2 || shelves > 12) {
        std::fprintf(stderr,
            "gen-mesh-bookshelf: dims > 0; shelves must be 2..12\n");
        return 1;
    }
    if (womBase.size() >= 4 &&
        womBase.substr(womBase.size() - 4) == ".wom") {
        womBase = womBase.substr(0, womBase.size() - 4);
    }
    wowee::pipeline::WoweeModel wom;
    wom.name = std::filesystem::path(womBase).stem().string();
    wom.version = 3;
    auto addBox = [&](float cx, float cy, float cz,
                      float hx, float hy, float hz) {
        struct Face { glm::vec3 n, du, dv; };
        Face faces[6] = {
            {{0, 1, 0}, {1, 0, 0}, {0, 0, 1}},
            {{0,-1, 0}, {1, 0, 0}, {0, 0,-1}},
            {{1, 0, 0}, {0, 0, 1}, {0, 1, 0}},
            {{-1,0, 0}, {0, 0,-1}, {0, 1, 0}},
            {{0, 0, 1}, {-1,0, 0}, {0, 1, 0}},
            {{0, 0,-1}, {1, 0, 0}, {0, 1, 0}},
        };
        glm::vec3 c(cx, cy, cz);
        glm::vec3 ext(hx, hy, hz);
        for (const Face& f : faces) {
            glm::vec3 center = c + glm::vec3(f.n.x*hx, f.n.y*hy, f.n.z*hz);
            glm::vec3 du = glm::vec3(f.du.x*ext.x, f.du.y*ext.y, f.du.z*ext.z);
            glm::vec3 dv = glm::vec3(f.dv.x*ext.x, f.dv.y*ext.y, f.dv.z*ext.z);
            uint32_t base = static_cast<uint32_t>(wom.vertices.size());
            auto push = [&](glm::vec3 p, float u, float v) {
                wowee::pipeline::WoweeModel::Vertex vtx;
                vtx.position = p; vtx.normal = f.n; vtx.texCoord = {u, v};
                wom.vertices.push_back(vtx);
            };
            push(center - du - dv, 0, 0);
            push(center + du - dv, 1, 0);
            push(center + du + dv, 1, 1);
            push(center - du + dv, 0, 1);
            wom.indices.insert(wom.indices.end(),
                {base, base + 1, base + 2, base, base + 2, base + 3});
        }
    };
    // Cabinet skin: thickness scales with the smaller cabinet
    // dimension so the shelf reads at any size without becoming
    // either too chunky or too flimsy.
    float panelT = std::min(width, depth) * 0.06f;
    float halfW = width  * 0.5f;
    float halfD = depth  * 0.5f;
    // Bottom + top panels span full width and depth.
    addBox(0, panelT * 0.5f, 0,
           halfW, panelT * 0.5f, halfD);
    addBox(0, height - panelT * 0.5f, 0,
           halfW, panelT * 0.5f, halfD);
    // Left + right side panels span between bottom and top panels.
    float sideCY = (panelT + (height - panelT)) * 0.5f;
    float sideHY = (height - 2 * panelT) * 0.5f;
    addBox(-halfW + panelT * 0.5f, sideCY, 0,
           panelT * 0.5f, sideHY, halfD);
    addBox( halfW - panelT * 0.5f, sideCY, 0,
           panelT * 0.5f, sideHY, halfD);
    // Back panel — thin slab at the rear of the cabinet.
    addBox(0, sideCY, -halfD + panelT * 0.5f,
           halfW - panelT, sideHY, panelT * 0.5f);
    // Horizontal shelves divide the interior into 'shelves' bays.
    // shelf[0] is the cabinet bottom, shelf[shelves] is the top —
    // we only emit the (shelves-1) interior shelves between them.
    float interiorTop = height - panelT;
    float interiorBottom = panelT;
    float bayHeight = (interiorTop - interiorBottom) /
                      static_cast<float>(shelves);
    float shelfT = panelT;  // shelf thickness matches panel skin
    float interiorHalfW = halfW - panelT;
    for (int s = 1; s < shelves; ++s) {
        float shelfCY = interiorBottom + s * bayHeight - shelfT * 0.5f;
        addBox(0, shelfCY, 0,
               interiorHalfW, shelfT * 0.5f, halfD - panelT * 0.5f);
    }
    // Books: per-bay row of thin boxes leaning along the shelf.
    // Pseudo-random width/height variation seeded by bay index so
    // re-generating the same shelf gives the same layout.
    auto rngStep = [](uint32_t& s) {
        s ^= s << 13; s ^= s >> 17; s ^= s << 5;
        return s;
    };
    int totalBooks = 0;
    for (int s = 0; s < shelves; ++s) {
        // Bottom Y of this bay's books = top of the shelf below.
        float bayBottomY = (s == 0) ? interiorBottom
                                    : interiorBottom + s * bayHeight;
        float bayTopY    = interiorBottom + (s + 1) * bayHeight - shelfT;
        if (s == shelves - 1) bayTopY = interiorTop - shelfT;
        float availableH = bayTopY - bayBottomY;
        if (availableH < bayHeight * 0.3f) continue;
        // Lay books from left to right with narrow gaps. Variable
        // book widths are 50–120% of nominal — yields ~6 books per
        // bay at default size.
        float nominalBookW = bayHeight * 0.18f;
        float bookHalfD    = (halfD - panelT) * 0.7f;
        uint32_t rng = static_cast<uint32_t>(s * 0x9E3779B9u + 1);
        float cursor = -interiorHalfW + nominalBookW * 0.6f;
        while (cursor + nominalBookW < interiorHalfW) {
            float wScale = 0.5f + (rngStep(rng) & 0xFFFF) / 65535.0f * 0.7f;
            float hScale = 0.7f + (rngStep(rng) & 0xFFFF) / 65535.0f * 0.3f;
            float bookW  = nominalBookW * wScale;
            float bookH  = availableH * 0.85f * hScale;
            if (cursor + bookW > interiorHalfW) break;
            addBox(cursor + bookW * 0.5f,
                   bayBottomY + bookH * 0.5f,
                   0,
                   bookW * 0.5f, bookH * 0.5f, bookHalfD);
            cursor += bookW + nominalBookW * 0.05f;
            totalBooks++;
        }
    }
    wowee::pipeline::WoweeModel::Batch batch;
    batch.indexStart = 0;
    batch.indexCount = static_cast<uint32_t>(wom.indices.size());
    batch.textureIndex = 0;
    wom.batches.push_back(batch);
    wom.boundMin = glm::vec3(-halfW, 0.0f,    -halfD);
    wom.boundMax = glm::vec3( halfW, height,   halfD);
    if (!wowee::pipeline::WoweeModelLoader::save(wom, womBase)) {
        std::fprintf(stderr,
            "gen-mesh-bookshelf: failed to save %s.wom\n", womBase.c_str());
        return 1;
    }
    std::printf("Wrote %s.wom\n", womBase.c_str());
    std::printf("  size       : %.3f x %.3f x %.3f\n", width, height, depth);
    std::printf("  shelves    : %d (%d books across all bays)\n",
                shelves, totalBooks);
    std::printf("  vertices   : %zu\n", wom.vertices.size());
    std::printf("  triangles  : %zu\n", wom.indices.size() / 3);
    return 0;
}

}  // namespace

bool handleGenMesh(int& i, int argc, char** argv, int& outRc) {
    // Match --gen-mesh-textured BEFORE the bare --gen-mesh dispatcher.
    // strcmp is exact-match so the order doesn't actually matter, but
    // keeping the longer name first matches the convention used for
    // --gen-texture-noise vs --gen-texture-noise-color.
    if (std::strcmp(argv[i], "--gen-mesh-textured") == 0 && i + 3 < argc) {
        outRc = handleTextured(i, argc, argv); return true;
    }
    if (std::strcmp(argv[i], "--gen-mesh") == 0 && i + 2 < argc) {
        outRc = handleMeshDispatch(i, argc, argv); return true;
    }
    if (std::strcmp(argv[i], "--gen-mesh-stairs") == 0 && i + 2 < argc) {
        outRc = handleStairs(i, argc, argv); return true;
    }
    if (std::strcmp(argv[i], "--gen-mesh-grid") == 0 && i + 2 < argc) {
        outRc = handleGrid(i, argc, argv); return true;
    }
    if (std::strcmp(argv[i], "--gen-mesh-disc") == 0 && i + 1 < argc) {
        outRc = handleDisc(i, argc, argv); return true;
    }
    if (std::strcmp(argv[i], "--gen-mesh-tube") == 0 && i + 1 < argc) {
        outRc = handleTube(i, argc, argv); return true;
    }
    if (std::strcmp(argv[i], "--gen-mesh-capsule") == 0 && i + 1 < argc) {
        outRc = handleCapsule(i, argc, argv); return true;
    }
    if (std::strcmp(argv[i], "--gen-mesh-arch") == 0 && i + 1 < argc) {
        outRc = handleArch(i, argc, argv); return true;
    }
    if (std::strcmp(argv[i], "--gen-mesh-pyramid") == 0 && i + 1 < argc) {
        outRc = handlePyramid(i, argc, argv); return true;
    }
    if (std::strcmp(argv[i], "--gen-mesh-fence") == 0 && i + 1 < argc) {
        outRc = handleFence(i, argc, argv); return true;
    }
    if (std::strcmp(argv[i], "--gen-mesh-tree") == 0 && i + 1 < argc) {
        outRc = handleTree(i, argc, argv); return true;
    }
    if (std::strcmp(argv[i], "--gen-mesh-rock") == 0 && i + 1 < argc) {
        outRc = handleRock(i, argc, argv); return true;
    }
    if (std::strcmp(argv[i], "--gen-mesh-pillar") == 0 && i + 1 < argc) {
        outRc = handlePillar(i, argc, argv); return true;
    }
    if (std::strcmp(argv[i], "--gen-mesh-bridge") == 0 && i + 1 < argc) {
        outRc = handleBridge(i, argc, argv); return true;
    }
    if (std::strcmp(argv[i], "--gen-mesh-tower") == 0 && i + 1 < argc) {
        outRc = handleTower(i, argc, argv); return true;
    }
    if (std::strcmp(argv[i], "--gen-mesh-house") == 0 && i + 1 < argc) {
        outRc = handleHouse(i, argc, argv); return true;
    }
    if (std::strcmp(argv[i], "--gen-mesh-fountain") == 0 && i + 1 < argc) {
        outRc = handleFountain(i, argc, argv); return true;
    }
    if (std::strcmp(argv[i], "--gen-mesh-statue") == 0 && i + 1 < argc) {
        outRc = handleStatue(i, argc, argv); return true;
    }
    if (std::strcmp(argv[i], "--gen-mesh-altar") == 0 && i + 1 < argc) {
        outRc = handleAltar(i, argc, argv); return true;
    }
    if (std::strcmp(argv[i], "--gen-mesh-portal") == 0 && i + 1 < argc) {
        outRc = handlePortal(i, argc, argv); return true;
    }
    if (std::strcmp(argv[i], "--gen-mesh-archway") == 0 && i + 1 < argc) {
        outRc = handleArchway(i, argc, argv); return true;
    }
    if (std::strcmp(argv[i], "--gen-mesh-barrel") == 0 && i + 1 < argc) {
        outRc = handleBarrel(i, argc, argv); return true;
    }
    if (std::strcmp(argv[i], "--gen-mesh-chest") == 0 && i + 1 < argc) {
        outRc = handleChest(i, argc, argv); return true;
    }
    if (std::strcmp(argv[i], "--gen-mesh-anvil") == 0 && i + 1 < argc) {
        outRc = handleAnvil(i, argc, argv); return true;
    }
    if (std::strcmp(argv[i], "--gen-mesh-mushroom") == 0 && i + 1 < argc) {
        outRc = handleMushroom(i, argc, argv); return true;
    }
    if (std::strcmp(argv[i], "--gen-mesh-cart") == 0 && i + 1 < argc) {
        outRc = handleCart(i, argc, argv); return true;
    }
    if (std::strcmp(argv[i], "--gen-mesh-banner") == 0 && i + 1 < argc) {
        outRc = handleBanner(i, argc, argv); return true;
    }
    if (std::strcmp(argv[i], "--gen-mesh-grave") == 0 && i + 1 < argc) {
        outRc = handleGrave(i, argc, argv); return true;
    }
    if (std::strcmp(argv[i], "--gen-mesh-bench") == 0 && i + 1 < argc) {
        outRc = handleBench(i, argc, argv); return true;
    }
    if (std::strcmp(argv[i], "--gen-mesh-shrine") == 0 && i + 1 < argc) {
        outRc = handleShrine(i, argc, argv); return true;
    }
    if (std::strcmp(argv[i], "--gen-mesh-totem") == 0 && i + 1 < argc) {
        outRc = handleTotem(i, argc, argv); return true;
    }
    if (std::strcmp(argv[i], "--gen-mesh-cage") == 0 && i + 1 < argc) {
        outRc = handleCage(i, argc, argv); return true;
    }
    if (std::strcmp(argv[i], "--gen-mesh-throne") == 0 && i + 1 < argc) {
        outRc = handleThrone(i, argc, argv); return true;
    }
    if (std::strcmp(argv[i], "--gen-mesh-coffin") == 0 && i + 1 < argc) {
        outRc = handleCoffin(i, argc, argv); return true;
    }
    if (std::strcmp(argv[i], "--gen-mesh-bookshelf") == 0 && i + 1 < argc) {
        outRc = handleBookshelf(i, argc, argv); return true;
    }
    if (std::strcmp(argv[i], "--gen-mesh-table") == 0 && i + 1 < argc) {
        outRc = handleTable(i, argc, argv); return true;
    }
    if (std::strcmp(argv[i], "--gen-mesh-lamppost") == 0 && i + 1 < argc) {
        outRc = handleLamppost(i, argc, argv); return true;
    }
    if (std::strcmp(argv[i], "--gen-mesh-bed") == 0 && i + 1 < argc) {
        outRc = handleBed(i, argc, argv); return true;
    }
    return false;
}

}  // namespace cli
}  // namespace editor
}  // namespace wowee