西风逍遥游
72252ad218
Add a deterministic low-poly small-bush recipe to procgen. It clusters
squashed foliage ellipsoids under a dome silhouette, adds emergent woody
twigs and optional leaf cards, using a two-region atlas (bark/foliage)
consistent with mesh.tree.
- src/modules/procgen/algorithms/BushMesh.{h,cpp}: recipe implementation
- MarchingCubes.cpp: register mesh.bush in MeshRecipeRegistry
- test/procgen.cpp: reproducibility/styles, option validation, render dump
- examples/bush-generator/: interactive showcase + Kenney CC0 mini-forest
derived atlas with attribution
- docs/dev/程序化生成模块设计.md: document mesh.bush
Verified: procgen suite 57/57 passing, render dump produces 900x700 PNG.
2.7 KiB
Bush Lab — procedural small 3D bush (mesh.bush)
mesh.bush is a native EVEngine procedural mesh recipe that generates a small,
low-poly 3D bush deterministically. The same seed and parameters always produce
the identical mesh (positions, normals, UVs and indices).
Run from the repository root:
make run/win32-debug GAME=examples/bush-generator # Windows Debug
make run GAME=examples/bush-generator # current host debug
How it works
procgen.generateMesh("mesh.bush", p, gfx) returns a GPU Mesh; use
procgen.buildMesh("mesh.bush", p) for the CPU MeshBuild. The generator
clusters a set of squashed foliage ellipsoids under a dome silhouette, adds a
few woody twigs poking out, and optionally scatters loose leaf cards.
The mesh uses a two-region atlas, matching the mesh.tree convention:
| Region | UV.u | Content |
|---|---|---|
| Twigs / bark | [0.0, 0.45] |
woody emergent stems |
| Foliage | [0.55, 1.0] |
lobes + leaf cards |
Parameters
| Key | Default | Meaning |
|---|---|---|
seed |
(from newParams) |
deterministic source |
style |
mound |
mound (flattened dome) or sphere (round ball) |
leafMode |
mixed |
blobs | cards | mixed | none |
height |
1.4 |
overall height |
width |
2.2 |
overall width (diameter) |
blobs |
9 |
number of foliage lobes |
rings |
3 |
lobe ring resolution |
radialSegments |
7 |
lobe radial resolution |
leafDensity |
0.62 |
fraction of loose leaf cards |
leafSize |
0.16·height |
leaf-card size |
twigs |
4 |
emergent woody twigs (0 disables) |
twigLength |
0.30·height |
twig length |
Squirrel example:
local p = procgen.newParams();
p.setSeed(20260815);
p.setString("style", "mound");
p.setString("leafMode", "mixed");
p.setFloat("height", 1.7);
local mesh = procgen.generateMesh("mesh.bush", p, gfx);
Controls
| Key | Action |
|---|---|
R |
new seed |
1 / 2 |
mound / sphere style |
L |
cycle leaf mode (mixed → blobs → cards → none) |
C |
toggle leaf cards |
[ / ] |
leaf density down / up |
T |
reload texture from disk |
Assets & attribution
The default texture assets/bush_atlas.png is a two-tone atlas (brown twig
half + green foliage half) derived from the color palette of the
Kenney "Mini Forest" pack. The original
assets/kenney/kenney_mini-forest_colormap.png and its
assets/kenney/LICENSE.txt are included.
Kenney assets are released under CC0 1.0 (public domain) — no attribution required, but appreciated. See
assets/kenney/LICENSE.txtfor the full license text.