feat(editor): add --gen-texture-mold Worley-noise patches

72nd procedural texture: Worley (cellular) noise thresholded
into mold patches. Each grid cell hosts a hash-jittered
center; each pixel computes its distance to the nearest
center across 9 surrounding cells (current + 8 neighbors)
and is painted as mold if that distance is below
thresholdFrac × stride.

Distinct from --gen-texture-moss (single-spot per cell with
hash-derived presence/jitter/radius) — mold has irregular
field-shaped patches following the Voronoi cell boundaries
rather than discrete circles, mimicking real fungal growth
along surfaces.

Useful for cellars, dungeon walls, plague zones, sewer
overflow, food-warehouse spoilage, witch-hut detail trim.
Default 18-stride / 0.55-threshold gives a moderate
infestation; bump threshold near 0.9 for full coverage.
This commit is contained in:
Kelsi 2026-05-09 13:19:30 -07:00
parent e95e983988
commit 805f7ce240
3 changed files with 90 additions and 1 deletions

View file

@ -107,7 +107,7 @@ const char* const kArgRequired[] = {
"--gen-texture-plaid", "--gen-texture-diamond-grid",
"--gen-texture-houndstooth", "--gen-texture-chevron",
"--gen-texture-dunes", "--gen-texture-swirl",
"--gen-texture-ironbark",
"--gen-texture-ironbark", "--gen-texture-mold",
"--validate-glb", "--info-glb", "--info-glb-tree", "--info-glb-bytes",
"--validate-jsondbc", "--check-glb-bounds", "--validate-stl",
"--validate-png", "--validate-blp",

View file

@ -3500,6 +3500,92 @@ int handleKnit(int& i, int argc, char** argv) {
return 0;
}
int handleMold(int& i, int argc, char** argv) {
// Mold: Worley (cellular) noise thresholded into mold patches.
// Each grid cell hosts a hash-jittered center; each pixel
// computes its distance to the nearest center across 9 cells
// (current + 8 neighbors) and is painted as mold if that
// distance is under a fraction of stride. Distinct from
// --gen-texture-moss (single-spot per cell with hash-derived
// presence/jitter/radius) — mold has irregular field-shaped
// patches rather than discrete circles, mimicking real fungal
// growth. Useful for cellars, dungeon walls, plague zones,
// sewer overflow, food-warehouse spoilage.
std::string outPath = argv[++i];
std::string bgHex = argv[++i];
std::string moldHex = argv[++i];
int stride = 18;
float thresholdFrac = 0.55f; // 0..1 of half-stride to count as mold
uint32_t seed = 1;
int W = 256, H = 256;
parseOptInt(i, argc, argv, stride);
parseOptFloat(i, argc, argv, thresholdFrac);
parseOptUint(i, argc, argv, seed);
parseOptInt(i, argc, argv, W);
parseOptInt(i, argc, argv, H);
if (W < 1 || H < 1 || W > 8192 || H > 8192 ||
stride < 4 || stride > 1024 ||
thresholdFrac <= 0.0f || thresholdFrac > 1.0f) {
std::fprintf(stderr,
"gen-texture-mold: invalid dims (W/H 1..8192, "
"stride 4..1024, thresholdFrac (0,1])\n");
return 1;
}
uint8_t br_, bg_, bb_, mr, mg, mb_;
if (!parseHexOrError(bgHex, br_, bg_, bb_, "gen-texture-mold")) return 1;
if (!parseHexOrError(moldHex, mr, mg, mb_,
"gen-texture-mold")) return 1;
auto hash32 = [](uint32_t x) -> uint32_t {
x ^= x >> 16; x *= 0x7feb352d;
x ^= x >> 15; x *= 0x846ca68b;
x ^= x >> 16; return x;
};
auto cellHash = [&](int cx, int cy, uint32_t salt) -> uint32_t {
uint32_t h = static_cast<uint32_t>(cx) * 0x9E3779B1u
^ static_cast<uint32_t>(cy) * 0x85EBCA77u
^ seed ^ salt;
return hash32(h);
};
std::vector<uint8_t> pixels(static_cast<size_t>(W) * H * 3, 0);
const float threshold = thresholdFrac * stride;
for (int y = 0; y < H; ++y) {
int cellY = y / stride;
for (int x = 0; x < W; ++x) {
int cellX = x / stride;
// Distance to nearest center across 9 surrounding cells.
float minDist = 1e9f;
for (int dy = -1; dy <= 1; ++dy) {
for (int dx = -1; dx <= 1; ++dx) {
int cx = cellX + dx;
int cy = cellY + dy;
float jx = (cellHash(cx, cy, 1) % 1000) / 1000.0f;
float jy = (cellHash(cx, cy, 2) % 1000) / 1000.0f;
float scx = (cx + jx) * stride;
float scy = (cy + jy) * stride;
float ddx = x - scx;
float ddy = y - scy;
float d2 = ddx * ddx + ddy * ddy;
if (d2 < minDist) minDist = d2;
}
}
float d = std::sqrt(minDist);
uint8_t r, g, b;
if (d < threshold) {
r = mr; g = mg; b = mb_;
} else {
r = br_; g = bg_; b = bb_;
}
setPixelRGB(pixels, W, x, y, r, g, b);
}
}
if (!savePngOrError(outPath, W, H, pixels, "gen-texture-mold")) return 1;
printPngWrote(outPath, W, H);
std::printf(" bg/mold : %s / %s\n", bgHex.c_str(), moldHex.c_str());
std::printf(" Worley : stride=%d, threshold=%.2f, seed=%u\n",
stride, thresholdFrac, seed);
return 0;
}
int handleIronbark(int& i, int argc, char** argv) {
// Ironbark: vertical wood-grain streaks (like --gen-texture-
// bark) overlaid with horizontal "plate" bands at regular
@ -5231,6 +5317,7 @@ constexpr TextureEntry kTextureTable[] = {
{"--gen-texture-dunes", 3, handleDunes},
{"--gen-texture-swirl", 3, handleSwirl},
{"--gen-texture-ironbark", 3, handleIronbark},
{"--gen-texture-mold", 3, handleMold},
};
} // namespace

View file

@ -177,6 +177,8 @@ void printUsage(const char* argv0) {
std::printf(" Swirl: N-arm logarithmic spiral (magic sigils / summoning circles / ritual floor markings)\n");
std::printf(" --gen-texture-ironbark <out.png> <baseHex> <crackHex> [streakSpacing] [plateY] [crackW] [seed] [W H]\n");
std::printf(" Ironbark: vertical wood streaks + horizontal plate bands (mature hardwood / sycamore / ironwood)\n");
std::printf(" --gen-texture-mold <out.png> <bgHex> <moldHex> [stride] [thresholdFrac] [seed] [W H]\n");
std::printf(" Mold: Worley-noise field patches (cellars / dungeon walls / sewer overflow / fungal growth)\n");
std::printf(" --add-texture-to-zone <zoneDir> <png-path> [renameTo]\n");
std::printf(" Copy an existing PNG into <zoneDir> (optionally renaming it on the way in)\n");
std::printf(" --gen-mesh <wom-base> <cube|plane|sphere|cylinder|torus|cone|ramp> [size]\n");