feat: foilage

AGENTS.md

@@ -69,7 +69,9 @@ rules live in `.agents/rules/*.md`.
     (procedural low-poly oak/spruce geometry, sapling..full via a `growth` knob;
     `Tree.build` appends into shared trunk + foliage meshes), `Boulder`
     (procedural low-poly rock: a squashed, jittered, part-buried sphere;
-    `Boulder.build` appends into a shared mesh).
+    `Boulder.build` appends into a shared mesh), `Bush` (cluster of small leaf
+    blobs, shares the oak leaf texture/mesh), `Flower` (thin stem + colored bloom;
+    samples a 2x2 color-atlas texture, drawn double-sided).
 - `app/` — browser glue.
   - `main.ts` — game loop, input, preset switching, canvas blit, FPS meter.
   - `assets.ts` — load `/assets/*.png` → `Texture` (zero-copy; ImageData bytes
@@ -77,12 +79,13 @@ rules live in `.agents/rules/*.md`.
   - `level.ts` — builds the playground: a flat stone-floored room (three thick
     walls via `slab`, north side open) always drawn, in the center of a big grassy
     `Terrain` world (~20x across). Props are placed first (`placeTrees` /
-    `placeBoulders` → instance lists + colliders; `TREE_/BOULDER_COUNT`/`_SEED`/
-    `_REACH`), then `buildChunks` bakes terrain + props into a `CHUNK_GRID` x
-    `CHUNK_GRID` grid of `Chunk`s (each = per-texture meshes grass/bark/leaf/needle/
-    rock + a tight AABB) that `main` frustum-culls. `Aabb` colliders (walls, crate,
-    grown trunks, big boulders), NPC position, `TERRAIN`/`TERRAIN_SUBDIV`/`GROUND_UV`,
-    sky/cloud config. The stone floor is lifted by `FLOOR_LIFT` (a z-bias) so it
+    `placeBoulders` / `placeBushes` / `placeFlowers` → instance lists + colliders;
+    `TREE_/BOULDER_/BUSH_/FLOWER_COUNT`/`_SEED`/`_REACH`), then `buildChunks` bakes
+    terrain + props into a `CHUNK_GRID` x `CHUNK_GRID` grid of `Chunk`s (each =
+    per-texture meshes grass/bark/leaf/needle/rock/flowers + a tight AABB) that
+    `main` frustum-culls; bushes fold into the leaf mesh, flowers get their own
+    (drawn double-sided). `Aabb` colliders (walls, crate, grown trunks, big
+    boulders), NPC position, `TERRAIN`/`TERRAIN_SUBDIV`/`GROUND_UV`, sky/cloud config. The stone floor is lifted by `FLOOR_LIFT` (a z-bias) so it
     stays clean over the terrain skirt that laps under the room edges. Room surfaces
     are single flat quads -- no subdivision needed since texturing is
     perspective-correct.
@@ -94,9 +97,10 @@ rules live in `.agents/rules/*.md`.
   `#fps` meter div (styled inline).
 - `scripts/gen-assets.ts` — procedurally draws the placeholder textures and
   writes PNGs (hand-rolled encoder via `node:zlib`). Run via `bun run assets`.
-- `assets/` — generated `floor/grass/bark/leaf/needle/rock/wall/crate/npc` PNGs
-  (`floor` = room stone, `grass` = outdoor ground, `bark`/`leaf`/`needle` = tree
-  trunk/oak/spruce, `rock` = boulders). Swap for real art anytime;
+- `assets/` — generated `floor/grass/bark/leaf/needle/rock/flower/wall/crate/npc`
+  PNGs (`floor` = room stone, `grass` = outdoor ground, `bark`/`leaf`/`needle` =
+  tree trunk/oak/spruce, `rock` = boulders, `flower` = 2x2 bloom-color atlas).
+  Swap for real art anytime;
   filenames are the contract.
 - `server/` — Bun server stub. `shared/` — isomorphic slot.
 
@@ -106,7 +110,8 @@ rules live in `.agents/rules/*.md`.
 `Sky.render` at 1/`SKY_STEP` res (fills color + resets depth, replaces a clear) →
 `Rasterizer.draw` floor, walls, crate (room, always) → `Frustum.fromViewProj`,
 then for each `Chunk` that `Frustum.intersectsAabb` passes: draw its grass, rock,
-bark, leaf, needle (backface-culled) → `Sprite.billboard(npc)` (double-sided) →
+bark, leaf, needle (backface-culled) + flowers (double-sided) →
+`Sprite.billboard(npc)` (double-sided) →
 `Framebuffer.quantize` → `present` (integer-scale, letterboxed blit;
 `imageSmoothingEnabled` follows `upscaleFilter`).
 
@@ -190,7 +195,9 @@ canopy blobs (oak) / tiers (spruce); `seed` gives each tree its own wobble.
 appends a squashed, per-vertex-jittered low-poly sphere (seam/pole-safe so it
 never cracks) into one shared rock mesh, sunk partway into the ground.
 `scatterBoulders` sizes them small→big (biased small) and drops colliders on the
-big ones.
+big ones. `Bush` (leaf-blob clusters) and `Flower` (stem + colored bloom, atlas
+UVs) are the same again — ground detail scattered near the play area, no
+colliders; add a new prop type by cloning the pattern (generator + scatter).
 
 ## Controls
 

app/assets.ts

@@ -2,6 +2,7 @@ import type { Texture } from "../engine/render/Texture"
 import barkUrl from "../assets/bark.png"
 import crateUrl from "../assets/crate.png"
 import floorUrl from "../assets/floor.png"
+import flowerUrl from "../assets/flower.png"
 import grassUrl from "../assets/grass.png"
 import leafUrl from "../assets/leaf.png"
 import needleUrl from "../assets/needle.png"
@@ -16,6 +17,7 @@ export type Textures = {
   leaf: Texture
   needle: Texture
   rock: Texture
+  flower: Texture
   wall: Texture
   crate: Texture
   npc: Texture
@@ -23,18 +25,19 @@ export type Textures = {
 
 /** Load every game texture up front. Call once before starting the loop. */
 export async function loadTextures(): Promise<Textures> {
-  const [floor, grass, bark, leaf, needle, rock, wall, crate, npc] = await Promise.all([
+  const [floor, grass, bark, leaf, needle, rock, flower, wall, crate, npc] = await Promise.all([
     loadTexture(floorUrl),
     loadTexture(grassUrl),
     loadTexture(barkUrl),
     loadTexture(leafUrl),
     loadTexture(needleUrl),
     loadTexture(rockUrl),
+    loadTexture(flowerUrl),
     loadTexture(wallUrl),
     loadTexture(crateUrl),
     loadTexture(npcUrl),
   ])
-  return { floor, grass, bark, leaf, needle, rock, wall, crate, npc }
+  return { floor, grass, bark, leaf, needle, rock, flower, wall, crate, npc }
 }
 
 function loadTexture(url: string): Promise<Texture> {

app/level.ts

@@ -2,6 +2,8 @@ import { Color } from "../engine/render/Color"
 import type { CloudLayer, SkyConfig } from "../engine/render/Sky"
 import { STRIDE, type Mesh } from "../engine/scene/Mesh"
 import { Boulder } from "../engine/scene/Boulder"
+import { Bush } from "../engine/scene/Bush"
+import { Flower, type FlowerColor } from "../engine/scene/Flower"
 import { Terrain } from "../engine/scene/Terrain"
 import { Tree } from "../engine/scene/Tree"
 
@@ -35,6 +37,8 @@ export type Chunk = {
   leaf: Mesh
   needle: Mesh
   rock: Mesh
+  /** Flowers (color-atlas texture); drawn double-sided, so kept separate. */
+  flowers: Mesh
 }
 
 /** The playground: a flat-floored room dropped into the center of a big open
@@ -91,6 +95,16 @@ const BOULDER_COUNT = 70
 const BOULDER_SEED = 0xB0142
 const BOULDER_REACH = 0.7
 
+/** Bushes + flowers: ground detail, kept to the nearer band since they're small
+ *  and fog/size hides them far out. Flowers roll white/red/yellow. */
+const BUSH_COUNT = 140
+const BUSH_SEED = 0xB554
+const BUSH_REACH = 0.35
+const FLOWER_COUNT = 340
+const FLOWER_SEED = 0xF10E
+const FLOWER_REACH = 0.3
+const FLOWER_COLORS: FlowerColor[] = ["white", "red", "yellow"]
+
 /** Spatial partition of the world for frustum culling: `CHUNK_GRID` x
  *  `CHUNK_GRID` square cells over [-outer, outer]. Smaller cells cull tighter
  *  (less drawn off-screen) but cost more per-cell tests + bounds; this is the
@@ -175,15 +189,18 @@ export function buildLevel(): Level {
   // frustum-cullable spatial chunks.
   const trees = placeTrees(colliders)
   const boulders = placeBoulders(colliders)
-  const chunks = buildChunks(trees, boulders)
+  const bushes = placeBushes()
+  const flowers = placeFlowers()
+  const chunks = buildChunks(trees, boulders, bushes, flowers)
 
   return { floor, walls, crate, chunks, colliders, npcPosition, terrain: TERRAIN, sky }
 }
 
 /** Bake the terrain + props into a `CHUNK_GRID` x `CHUNK_GRID` set of spatial
  *  chunks. Each prop lands in the cell holding its base; the cell's bounds are
- *  grown to the real geometry so overhanging canopies never get culled early. */
-function buildChunks(trees: Tree[], boulders: Boulder[]): Chunk[] {
+ *  grown to the real geometry so overhanging canopies never get culled early.
+ *  Bushes share the oak leaf mesh; flowers get their own (double-sided) mesh. */
+function buildChunks(trees: Tree[], boulders: Boulder[], bushes: Bush[], flowers: Flower[]): Chunk[] {
   const cell = (TERRAIN.outer * 2) / CHUNK_GRID
   const chunks: Chunk[] = []
   for (let ci = 0; ci < CHUNK_GRID; ci++) {
@@ -197,6 +214,7 @@ function buildChunks(trees: Tree[], boulders: Boulder[]): Chunk[] {
       const leaf = mesh()
       const needle = mesh()
       const rock = mesh()
+      const flowerMesh = mesh()
       Terrain.patch(TERRAIN, grass, x0, z0, x1, z1, TERRAIN_SUBDIV, TERRAIN_SUBDIV, GROUND_UV)
       for (const tree of trees) {
         if (inCell(tree.position, x0, z0, x1, z1)) {
@@ -208,11 +226,21 @@ function buildChunks(trees: Tree[], boulders: Boulder[]): Chunk[] {
           Boulder.build(boulder, rock)
         }
       }
-      const b = bounds([grass, bark, leaf, needle, rock])
+      for (const bush of bushes) {
+        if (inCell(bush.position, x0, z0, x1, z1)) {
+          Bush.build(bush, leaf)
+        }
+      }
+      for (const flower of flowers) {
+        if (inCell(flower.position, x0, z0, x1, z1)) {
+          Flower.build(flower, flowerMesh)
+        }
+      }
+      const b = bounds([grass, bark, leaf, needle, rock, flowerMesh])
       if (b === null) {
         continue
       }
-      chunks.push({ ...b, grass, bark, leaf, needle, rock })
+      chunks.push({ ...b, grass, bark, leaf, needle, rock, flowers: flowerMesh })
     }
   }
   return chunks
@@ -302,6 +330,43 @@ function placeBoulders(colliders: Aabb[]): Boulder[] {
   return boulders
 }
 
+/** Scatter bushes on the grass near the play area (no colliders -- walk through). */
+function placeBushes(): Bush[] {
+  const rand = mulberry(BUSH_SEED)
+  const maxDist = TERRAIN.outer * BUSH_REACH
+  const bushes: Bush[] = []
+  for (let guard = 0; bushes.length < BUSH_COUNT && guard < BUSH_COUNT * 20; guard++) {
+    const angle = rand() * Math.PI * 2
+    const dist = ARENA + 3 + rand() * (maxDist - ARENA - 3)
+    const x = Math.cos(angle) * dist
+    const z = Math.sin(angle) * dist
+    if (Math.max(Math.abs(x), Math.abs(z)) < TERRAIN.inner + 2) {
+      continue
+    }
+    bushes.push({ position: { x, y: Terrain.height(TERRAIN, x, z), z }, size: 0.8 + rand() * 1, seed: (rand() * 0xFFFFFFFF) | 0 })
+  }
+  return bushes
+}
+
+/** Scatter small flowers on the grass near the play area, colors rolled. */
+function placeFlowers(): Flower[] {
+  const rand = mulberry(FLOWER_SEED)
+  const maxDist = TERRAIN.outer * FLOWER_REACH
+  const flowers: Flower[] = []
+  for (let guard = 0; flowers.length < FLOWER_COUNT && guard < FLOWER_COUNT * 20; guard++) {
+    const angle = rand() * Math.PI * 2
+    const dist = ARENA + 2 + rand() * (maxDist - ARENA - 2)
+    const x = Math.cos(angle) * dist
+    const z = Math.sin(angle) * dist
+    if (Math.max(Math.abs(x), Math.abs(z)) < TERRAIN.inner + 1) {
+      continue
+    }
+    const color = FLOWER_COLORS[(rand() * FLOWER_COLORS.length) | 0]
+    flowers.push({ position: { x, y: Terrain.height(TERRAIN, x, z), z }, color, size: 0.28 + rand() * 0.22, seed: (rand() * 0xFFFFFFFF) | 0 })
+  }
+  return flowers
+}
+
 /** Deterministic 0..1 generator (mulberry32) for tree placement. */
 function mulberry(seed: number): () => number {
   let a = seed >>> 0

app/main.ts

@@ -128,6 +128,7 @@ async function main(): Promise<void> {
       Rasterizer.draw(fb, c.bark, textures.bark, viewProj, config, true)
       Rasterizer.draw(fb, c.leaf, textures.leaf, viewProj, config, true)
       Rasterizer.draw(fb, c.needle, textures.needle, viewProj, config, true)
+      Rasterizer.draw(fb, c.flowers, textures.flower, viewProj, config)
     }
     Rasterizer.draw(fb, Sprite.billboard(npc, camera), npc.texture, viewProj, config)
     Framebuffer.quantize(fb, config)

engine/render/RenderConfig.ts

@@ -94,6 +94,7 @@ export namespace RenderConfig {
     colorDepth: 8,
     dither: 0,
     vertexSnap: 0,
+    perspectiveCorrect: 1,
     textureFilter: "linear",
     lighting: "flat",
     fog: null,

engine/scene/Bush.ts

@@ -0,0 +1,76 @@
+import type { Vec3 } from "../math/Vec3"
+import { STRIDE, type Mesh } from "./Mesh"
+
+const TAU = Math.PI * 2
+
+/** A low shrub: a tight cluster of small leafy blobs sitting on the ground.
+ *  Textured with the same leaf sheet as oak canopies, so it batches into the
+ *  chunk's foliage mesh. `size` is the overall spread; `seed` the per-bush wobble. */
+export type Bush = {
+  position: Vec3
+  size: number
+  seed: number
+}
+
+/** Low-poly bush geometry, same faceted flat-shaded style as the trees. A few
+ *  overlapping jittered spheres read as a rounded shrub; blobs are closed and
+ *  wound outward, so backface culling is safe. `build` appends into a shared
+ *  (leaf-textured) mesh. */
+export namespace Bush {
+  export function build(bush: Bush, mesh: Mesh): void {
+    const rand = rng(bush.seed)
+    // A handful of smaller overlapping lumps reads as a soft shrub; one big
+    // sphere reads as a boulder.
+    const blobs = 3 + Math.floor(rand() * 3)
+    const r = bush.size * 0.42
+    for (let i = 0; i < blobs; i++) {
+      const angle = rand() * TAU
+      const dist = i === 0 ? 0 : bush.size * 0.5 * rand()
+      const cx = bush.position.x + Math.cos(angle) * dist
+      const cz = bush.position.z + Math.sin(angle) * dist
+      const cy = bush.position.y + r * (0.5 + rand() * 0.4)
+      blob(mesh, cx, cy, cz, r * (0.55 + rand() * 0.3), rand)
+    }
+  }
+
+  /** A small lumpy low-poly sphere, wound outward (matches the oak canopy blob). */
+  function blob(mesh: Mesh, cx: number, cy: number, cz: number, radius: number, rand: () => number): void {
+    const seg = 6
+    const rings = 4
+    const start = mesh.verts.length / STRIDE
+    for (let r = 0; r <= rings; r++) {
+      const phi = (r / rings) * Math.PI
+      const cyv = Math.cos(phi)
+      const crv = Math.sin(phi)
+      const scale = radius * (0.9 + rand() * 0.18)
+      for (let s = 0; s <= seg; s++) {
+        const theta = (s / seg) * TAU
+        mesh.verts.push(
+          cx + crv * Math.cos(theta) * scale,
+          cy + cyv * scale,
+          cz + crv * Math.sin(theta) * scale,
+          (s / seg) * 2,
+          (r / rings) * 2,
+        )
+      }
+    }
+    const row = seg + 1
+    for (let r = 0; r < rings; r++) {
+      for (let s = 0; s < seg; s++) {
+        const p = start + r * row + s
+        mesh.indices.push(p, p + 1, p + row + 1, p, p + row + 1, p + row)
+      }
+    }
+  }
+
+  /** Deterministic 0..1 generator (mulberry32) seeded per bush. */
+  function rng(seed: number): () => number {
+    let a = seed >>> 0
+    return () => {
+      a = (a + 0x6D2B79F5) | 0
+      let t = Math.imul(a ^ (a >>> 15), 1 | a)
+      t ^= t + Math.imul(t ^ (t >>> 7), 61 | t)
+      return ((t ^ (t >>> 14)) >>> 0) / 4294967296
+    }
+  }
+}

engine/scene/Flower.ts

@@ -0,0 +1,79 @@
+import type { Vec3 } from "../math/Vec3"
+import { Mesh } from "./Mesh"
+
+const TAU = Math.PI * 2
+
+/** Flower bloom color, indexing a region of the `flower` texture atlas. */
+export type FlowerColor = "white" | "red" | "yellow"
+
+/** A single small flower: a thin crossed-quad stem plus a shallow fan of petals.
+ *  Tiny, so it is drawn double-sided (no backface cull) and carries no collider.
+ *  `size` is roughly its height; `seed` jitters the petals. */
+export type Flower = {
+  position: Vec3
+  color: FlowerColor
+  size: number
+  seed: number
+}
+
+/**
+ * Low-poly flower geometry. The `flower` texture is a 2x2 color atlas -- green
+ * (stem) plus white / red / yellow blooms -- and every vertex samples the flat
+ * center of one region, so a flower is solid-colored with no per-flower texture
+ * or draw call. `build` appends into one shared flower mesh.
+ */
+export namespace Flower {
+  /** uv center of each bloom color's atlas region (tile units). */
+  const BLOOM_UV: Record<FlowerColor, [number, number]> = {
+    white: [0.75, 0.25],
+    red: [0.25, 0.75],
+    yellow: [0.75, 0.75],
+  }
+  /** uv center of the green stem region. */
+  const STEM_U = 0.25
+  const STEM_V = 0.25
+
+  export function build(flower: Flower, mesh: Mesh): void {
+    const rand = rng(flower.seed)
+    const p = flower.position
+    const height = flower.size * (0.8 + rand() * 0.4)
+    const bloomY = p.y + height
+    const w = flower.size * 0.04
+    // Stem: two thin crossed quads so it reads from any angle.
+    stem(mesh, p.x, p.y, p.z, bloomY, w, 0)
+    stem(mesh, p.x, p.y, p.z, bloomY, 0, w)
+    // Bloom: a shallow fan of petals, center raised a touch so it domes.
+    const [bu, bv] = BLOOM_UV[flower.color]
+    const rad = flower.size * 0.38
+    const center = Mesh.push(mesh, p.x, bloomY + rad * 0.3, p.z, bu, bv)
+    const ring = center + 1
+    const petals = 5
+    for (let i = 0; i <= petals; i++) {
+      const angle = (i / petals) * TAU + rand() * 0.4
+      Mesh.push(mesh, p.x + Math.cos(angle) * rad, bloomY, p.z + Math.sin(angle) * rad, bu, bv)
+    }
+    for (let i = 0; i < petals; i++) {
+      mesh.indices.push(center, ring + i, ring + i + 1)
+    }
+  }
+
+  /** A thin vertical quad from the ground to `y1`, width along (dx, dz). */
+  function stem(mesh: Mesh, x: number, y0: number, z: number, y1: number, dx: number, dz: number): void {
+    const a = Mesh.push(mesh, x - dx, y0, z - dz, STEM_U, STEM_V)
+    const b = Mesh.push(mesh, x + dx, y0, z + dz, STEM_U, STEM_V)
+    const c = Mesh.push(mesh, x + dx, y1, z + dz, STEM_U, STEM_V)
+    const d = Mesh.push(mesh, x - dx, y1, z - dz, STEM_U, STEM_V)
+    mesh.indices.push(a, b, c, a, c, d)
+  }
+
+  /** Deterministic 0..1 generator (mulberry32) seeded per flower. */
+  function rng(seed: number): () => number {
+    let a = seed >>> 0
+    return () => {
+      a = (a + 0x6D2B79F5) | 0
+      let t = Math.imul(a ^ (a >>> 15), 1 | a)
+      t ^= t + Math.imul(t ^ (t >>> 7), 61 | t)
+      return ((t ^ (t >>> 14)) >>> 0) / 4294967296
+    }
+  }
+}

scripts/gen-assets.ts

@@ -151,6 +151,24 @@ const rock: Shade = (x, y) => {
   return [g, g + 3, g + 8, 255]
 }
 
+// Flower color atlas (2x2): green stem (top-left), white / red / yellow blooms.
+// Geometry samples each region's flat center, so a flower is one solid color.
+const flower: Shade = (x, y) => {
+  const n = noise(x, y) * 8
+  const left = x < 32
+  const top = y < 32
+  if (top && left) {
+    return [66 + n, 128 + n, 58 + n, 255]
+  }
+  if (top) {
+    return [238 + n, 240 + n, 245 + n, 255]
+  }
+  if (left) {
+    return [202 + n, 52 + n, 58 + n, 255]
+  }
+  return [240 + n, 208 + n, 72 + n, 255]
+}
+
 const wall: Shade = (x, y) => {
   const row = Math.floor(y / 16)
   const bx = (x + (row % 2) * 16) % 32
@@ -209,6 +227,7 @@ const assets: Array<[string, number, number, Shade]> = [
   ["leaf", 64, 64, leaf],
   ["needle", 64, 64, needle],
   ["rock", 64, 64, rock],
+  ["flower", 64, 64, flower],
   ["wall", 64, 64, wall],
   ["crate", 64, 64, crate],
   ["npc", 48, 64, npc],