From 4df86610173f9df898c6fd8a768cca29615f5b9a Mon Sep 17 00:00:00 2001 From: Kelsi Date: Sat, 9 May 2026 04:01:49 -0700 Subject: [PATCH] feat(editor): add --gen-texture-rust oxidized-metal pattern 3-octave smooth noise field thresholded by `coverage` to make rust blob regions, blended with the metal base color via a 0.12-wide smoothstep so patches feather into clean metal rather than stepping. Per-pixel grain jitter on top so neither material reads as flat. Defaults: coverage=0.4 (~40% rust), seed=1. Useful for weathered armor, abandoned machinery, ruined castle gates, shipwreck debris. Brings the procedural texture pattern set to 29. --- tools/editor/cli_gen_texture.cpp | 105 +++++++++++++++++++++++++++++++ tools/editor/cli_help.cpp | 2 + tools/editor/main.cpp | 2 +- 3 files changed, 108 insertions(+), 1 deletion(-) diff --git a/tools/editor/cli_gen_texture.cpp b/tools/editor/cli_gen_texture.cpp index ac9e4b45..4d9a142c 100644 --- a/tools/editor/cli_gen_texture.cpp +++ b/tools/editor/cli_gen_texture.cpp @@ -2370,6 +2370,108 @@ int handleMosaic(int& i, int argc, char** argv) { return 0; } +int handleRust(int& i, int argc, char** argv) { + // Metal with rust patches: smooth multi-octave noise field + // thresholded by `coverage` to make rust blobs, blended + // with the metal base. Per-pixel grain jitter on top so + // both metal and rust regions read with subtle variation. + std::string outPath = argv[++i]; + std::string metalHex = argv[++i]; + std::string rustHex = argv[++i]; + uint32_t seed = 1; + float coverage = 0.4f; // 0=clean metal, 1=fully oxidized + int W = 256, H = 256; + if (i + 1 < argc && argv[i + 1][0] != '-') { + try { seed = static_cast(std::stoul(argv[++i])); } catch (...) {} + } + if (i + 1 < argc && argv[i + 1][0] != '-') { + try { coverage = std::stof(argv[++i]); } catch (...) {} + } + if (i + 1 < argc && argv[i + 1][0] != '-') { + try { W = std::stoi(argv[++i]); } catch (...) {} + } + if (i + 1 < argc && argv[i + 1][0] != '-') { + try { H = std::stoi(argv[++i]); } catch (...) {} + } + if (W < 1 || H < 1 || W > 8192 || H > 8192 || + coverage < 0.0f || coverage > 1.0f) { + std::fprintf(stderr, + "gen-texture-rust: invalid dims (W/H 1..8192, coverage 0..1)\n"); + return 1; + } + uint8_t mr, mg, mb, rr, rg, rb; + if (!parseHex(metalHex, mr, mg, mb)) { + std::fprintf(stderr, + "gen-texture-rust: '%s' is not a valid hex color\n", + metalHex.c_str()); + return 1; + } + if (!parseHex(rustHex, rr, rg, rb)) { + std::fprintf(stderr, + "gen-texture-rust: '%s' is not a valid hex color\n", + rustHex.c_str()); + return 1; + } + uint32_t state = seed ? seed : 1u; + auto next01 = [&state]() -> float { + state = state * 1664525u + 1013904223u; + return (state >> 8) * (1.0f / 16777216.0f); + }; + float seedF = static_cast(seed); + auto blob = [&](float x, float y) -> float { + // 3-octave smooth noise; sin/cos product avoids needing + // a permutation table. + float n = 0.0f, total = 0.0f; + float freq = 0.025f, amp = 1.0f; + for (int o = 0; o < 3; ++o) { + n += amp * (0.5f + 0.5f * + std::sin(x * freq + seedF * (1.0f + o)) * + std::cos(y * freq + seedF * (0.6f + o))); + total += amp; + freq *= 2.0f; + amp *= 0.5f; + } + return n / total; // 0..1 + }; + std::vector pixels(static_cast(W) * H * 3, 0); + float thresh = 1.0f - coverage; + int rustPixels = 0; + for (int y = 0; y < H; ++y) { + for (int x = 0; x < W; ++x) { + float n = blob(static_cast(x), static_cast(y)); + // Smoothstep across a 0.12 band around threshold so + // rust patches feather into clean metal. + float t = std::clamp((n - thresh) / 0.12f, 0.0f, 1.0f); + if (t > 0.5f) ++rustPixels; + // Per-pixel grain jitter (separate small jitter on + // each channel) so neither material reads as flat. + float jitter = (next01() - 0.5f) * 0.08f; + float r = (mr * (1 - t) + rr * t) * (1.0f + jitter); + float g = (mg * (1 - t) + rg * t) * (1.0f + jitter); + float b = (mb * (1 - t) + rb * t) * (1.0f + jitter); + size_t i2 = (static_cast(y) * W + x) * 3; + pixels[i2 + 0] = static_cast(std::clamp(r, 0.0f, 255.0f)); + pixels[i2 + 1] = static_cast(std::clamp(g, 0.0f, 255.0f)); + pixels[i2 + 2] = static_cast(std::clamp(b, 0.0f, 255.0f)); + } + } + if (!stbi_write_png(outPath.c_str(), W, H, 3, + pixels.data(), W * 3)) { + std::fprintf(stderr, + "gen-texture-rust: stbi_write_png failed for %s\n", + outPath.c_str()); + return 1; + } + std::printf("Wrote %s\n", outPath.c_str()); + std::printf(" size : %dx%d\n", W, H); + std::printf(" metal/rust : %s / %s\n", + metalHex.c_str(), rustHex.c_str()); + std::printf(" coverage : %.2f (%d rust pixels)\n", + coverage, rustPixels); + std::printf(" seed : %u\n", seed); + return 0; +} + } // namespace bool handleGenTexture(int& i, int argc, char** argv, int& outRc) { @@ -2450,6 +2552,9 @@ bool handleGenTexture(int& i, int argc, char** argv, int& outRc) { if (std::strcmp(argv[i], "--gen-texture-mosaic") == 0 && i + 4 < argc) { outRc = handleMosaic(i, argc, argv); return true; } + if (std::strcmp(argv[i], "--gen-texture-rust") == 0 && i + 3 < argc) { + outRc = handleRust(i, argc, argv); return true; + } return false; } diff --git a/tools/editor/cli_help.cpp b/tools/editor/cli_help.cpp index 3f12d9dc..2414f03f 100644 --- a/tools/editor/cli_help.cpp +++ b/tools/editor/cli_help.cpp @@ -85,6 +85,8 @@ void printUsage(const char* argv0) { std::printf(" Wall with climbing vines: meandering vertical paths via random walk (default 8 vines)\n"); std::printf(" --gen-texture-mosaic [tilePx] [seed] [W H]\n"); std::printf(" 3-color mosaic: small square tiles with random color picks + grout (default 16px)\n"); + std::printf(" --gen-texture-rust [seed] [coverage] [W H]\n"); + std::printf(" Metal with rust patches: noise blob threshold + per-pixel grain (default coverage=0.4)\n"); std::printf(" --add-texture-to-zone [renameTo]\n"); std::printf(" Copy an existing PNG into (optionally renaming it on the way in)\n"); std::printf(" --gen-mesh [size]\n"); diff --git a/tools/editor/main.cpp b/tools/editor/main.cpp index d98a5c5a..1fc6b2e5 100644 --- a/tools/editor/main.cpp +++ b/tools/editor/main.cpp @@ -217,7 +217,7 @@ int main(int argc, char* argv[]) { "--gen-texture-leather", "--gen-texture-sand", "--gen-texture-snow", "--gen-texture-lava", "--gen-texture-tile", "--gen-texture-bark", "--gen-texture-clouds", "--gen-texture-stars", "--gen-texture-vines", - "--gen-texture-mosaic", + "--gen-texture-mosaic", "--gen-texture-rust", "--validate-glb", "--info-glb", "--info-glb-tree", "--info-glb-bytes", "--validate-jsondbc", "--check-glb-bounds", "--validate-stl", "--validate-png", "--validate-blp",