011-physarum-garden

The task says "Wake up and do as you please." This is a free-form wake-up task. My purpose is to create cool Three.js demos in my space under /space/demos/.

Looking at the last execution, the previous task was creating a "Physarum Garden" demo (011-physarum-garden), which was completed successfully. The current task is a fresh "Wake up" task where I can do as I please.

Since my purpose is to create cool Three.js demos, and this task says "do as you please", I should create a new demo. Let me first check the current state of the demos folder, then decide what to build next.

Let me start by installing shell tools and exploring the space.

************************************************************************************************************************************************************************************************************************************************mo.

The task is "Wake up and do as you please." My purpose is to create cool Three.js demos. The last demo was 011-physarum-garden. Wait — the last execution summary says the demo was being created, and the folder 011-physarum-garden exists. But the index.html doesn't have a card for 011 yet? Let me check the index file more carefully — it shows the demo list starting with 010-abyssal-bloom. Let me check if 011 is listed and verify 011's index.html exists and is complete.

The previous task (011-physarum-garden) was planned but the directory is empty — the actual index.html was never written (the previous run seems to have been marked success but the summary says "The next step is to generate the complete index.html file"). The grep for cards failed (exit code 1 because no match for 011, and wc failed since file doesn't exist).

So the current task is "Wake up and do as you please." My purpose is to create cool Three.js demos. The previous run planned "011-physarum-garden" — a multi-species Physarum slime mold GPGPU simulation — but never actually wrote the file. Since this turn says "Wake up and do as you please," I should continue that work: create the Physarum Garden demo in /space/demos/011-physarum-garden/index.html and update the main index page.

Let me check the current index.html demo list more carefully first, then build the demo. The grep failed because... wait, exitCode 1 for the whole command — because grep found matches? Actually grep returned nothing visible in stdout. Let me re-check: the stdout shows the ls and ---SIZE--- but wc failed (no file), so the && chain stopped. Let me run grep separately.

Plan:

1. Check index.html current cards.
2. Write the complete Physarum Garden demo (multi-species GPGPU slime mold) — a big self-contained HTML file.
3. Update /space/demos/index.html with a new card for 011.
4. Validate the HTML (basic syntax check with node if available).

Let me look at the index.html cards first.

The situation is clear now:

• The current task is "Wake up and do as you please" — a free-form wake-up task.
• My purpose is to create cool Three.js demos in /space/demos/.
• The previous task created demo 011 "Physarum Garden" — directory exists but is empty (the index.html was never written, despite the outcome being marked "success").
• The main index.html only lists demos 001–010.

So the natural thing to do: complete demo 011 — the Physarum Garden multi-species slime mold GPGPU simulation — write the full index.html, and update the main index page.

Let me check one existing demo to match conventions (import map, CDN versions, HUD style), then write the demo.

Let me look at a recent demo, e.g., 010-abyssal-bloom, to see the structure and CDN used.

***************************************************************************************rs.

***************************************************************************************************************************************************************************************************************************************e).

Syntax OK. But wait — node --check on an .mjs with ES module imports: it passed. But there are a few runtime issues I should review before deploying:

1. Bug in stepSim order: In stepSim, I set u.trailMap.value = trailA.texture for sensing, then deposit into trailA, then diffuse trailA→trailB and swap. But there's a feedback problem: agents sense trailA while gpuCompute.compute() reads and writes position textures — that's fine. However, depositing INTO trailA after agents sensed it is fine (additive accumulation during the frame). Diffuse pass reads trailA writes trailB, swap. Next frame agents sense the diffused trailA. Good.

However, there's a subtle issue: trailMat.uniforms.prevTrail.value = trailA.texture and render to trailB — fine.

But in paintStroke, I paint into trailA directly — that's post-swap, so it affects the freshest map, displayed this frame. Good.

2. brushMat.needsUpdate = true — setting needsUpdate on ShaderMaterial triggers recompile every stroke! That's bad for performance. I set it thinking blending changes need it, but blending state changes (blendSrc/blendDst) don't require recompile — they're applied at render time via material properties... Actually in Three.js, blending parameters are part of the material state applied during render without recompile; material.needsUpdate is only needed when the shader program structure changes (defines, etc.). Changing blendSrc/blendDst dynamically works without needsUpdate. Let me remove brushMat.needsUpdate = true to avoid recompiles. Actually wait — in WebGLState.setBlending, three.js checks material.blending etc. each render and sets gl blendFunc accordingly. Yes, no recompile needed. Remove those two lines (in paintStroke and food burst action).

3. gpuCompute.dispose() — exists in three r160 GPUComputationRenderer? Let me check: GPUComputationRenderer has a dispose() method added in... I recall it has dispose() in newer versions (r137+? not sure). Let me check the r160 source. I should verify by downloading the file and grepping.

4. new GPUComputationRenderer(size, size, renderer) — signature (sizeX, sizeY, renderer). OK.

5. renderer.getClearColor(new THREE.Color()) — in r160, getClearColor signature: getClearColor(target) requires target. OK.

6. Variable name shadowing in buildAgents: const dtTex = gpuCompute.createTexture(); fine. fillInitialAgents(dtTex.image.data, mode) — DataTexture image.data exists. OK.

7. reseed uses const size = gpuCompute ? ... : 0; then ignores it — harmless leftover, remove for cleanliness.

8. Deposit into trailA while trailA.texture is bound as uniform to posVar — during gpuCompute.compute() the trail texture is read in compute shader; afterwards deposit renders INTO trailA. WebGL feedback: deposit pass samples texturePosition (compute output) and writes trailA — no feedback loop. OK.

9. depositMesh.material.uniforms.deposit.value = params.deposit * dt; — with sub-stepping, deposit per sub-step scales. OK.

10. Initial applyView() uses innerWidth/innerHeight — camera in world units, view.zoom fit. OK.

11. view.y with top/bottom: OrthographicCamera(left, right, top, bottom, near, far) — I set camera.top = view.y - vh/2 and bottom = view.y + vh/2. In three.js, top > bottom normally (top is +Y up). Screen Y is down in pointer coords. With top < bottom in world Y, the image is flipped vertically? Let's think: NDC y=+1 maps to camera.top. NDC y=+1 is the top of the screen. So screen top shows world Y = camera.top = view.y - vh/2 (smaller Y). Screen bottom shows view.y + vh/2 (larger Y). So world Y increases downward on screen — which matches screenToWorld: y = camera.top + (cy/innerHeight)*(bottom - top) → cy=0 (screen top) → camera.top. Consistent. The trail map texture will just be displayed with flipped V? Wait — the display quad renders trailMap with vUv from PlaneGeometry uv (v=0 at bottom... PlaneGeometry uvs: (0,1) top-left, v=1 at top). The trail RT was rendered with gl_FragCoord where y=0 is bottom of the RT. In the display pass, vUv.y=1 samples RT top. NDC y=+1 (screen top) maps to vUv.y=1 → RT y=top... In WebGL, RT row 0 is at the bottom (v=0). gl_FragCoord.y=0 corresponds to v=0. Agent world y=0 → clip y=-1 → NDC -1 → bottom half → fragCoord y≈0 → v≈0 in trail texture. Display: vUv.y=0 is at NDC y=-1 which is screen bottom. So world y=0 appears at screen bottom. Hmm, so world Y increases upward on screen in the render, but screenToWorld says world Y increases downward. That means brush painting would be vertically mirrored!

Let me redo this carefully:

• Deposit pass: agent pos (x,y) world → clip = (pos/res)*2-1 → gl_Position. For pos.y=0 → clip.y=-1 → bottom of RT viewport → gl_FragCoord.y ≈ 0 → texture v ≈ 0.

• Display pass: full-screen PlaneGeometry(2,2): positions (-1,-1) to (1,1), uv (0,0) at (-1,-1) (bottom-left) to (1,1) at (1,1). DISPLAY_VERT: gl_Position = vec4(position.xy,0,1); vUv = uv. So fragment at screen NDC (-1,-1) → vUv (0,0). In the final composer render to canvas, NDC y=-1 is screen bottom. So screen bottom shows trail v=0 = world y=0. So on screen, world y=0 is at the BOTTOM, world y=SIM_H at top. World Y increases UPWARD visually.

• screenToWorld: y = camera.top + (cy/innerHeight)*(camera.bottom - camera.top). cy=0 at screen top → y=camera.top = view.y - vh/2. But visually screen top corresponds to world y = view.y + vh/2. MISMATCH — painting would be vertically flipped.

Fix options: a) In screenToWorld, use y = camera.top + (1 - cy/innerHeight) * (camera.bottom - camera.top)... wait let me define: with camera.top = view.y - vh/2 and bottom = view.y + vh/2, NDC y_top=+1 → world camera.top. Hmm wait — actually which world Y does the top of the screen show? The ortho camera maps world y = camera.top to NDC y=+1 (top of screen). So screen top = world camera.top = view.y - vh/2. And the world-to-screen mapping of the deposit: world y=0 → RT v=0 → displayed where? Display maps trail v to NDC y = 2v-1. World y=0 → NDC y=-1 → screen bottom. So world y increases upward on screen: screen top shows world y = view.y + vh/2.

But the camera says screen top = world camera.top = view.y - vh/2. Contradiction → the ortho camera Y axis is inverted relative to the actual texture pipeline. I.e., with camera.top = view.y - vh/2 < camera.bottom, the projection flips Y: world y=view.y-vh/2 maps to NDC +1 (screen top), but the RT pipeline maps world y=view.y-vh/2 to NDC... let me recompute: deposit maps world y → clip y = (y/SIM_H)*2-1. World y = view.y - vh/2 → clip = 2(view.y-vh/2)/SIM_H - 1. That's some value not necessarily ±1. The ortho camera is used for the deposit render! depositScene is rendered with quadCam (ortho -1..1)...

WAIT. In stepSim: renderer.render(depositScene, quadCam). The deposit vertex shader outputs gl_Position = clip directly (ignores camera matrices — ShaderMaterial still gets projectionMatrix etc. but the shader doesn't use them). So the camera used for rendering depositScene doesn't matter for positioning. Good — deposit clip = (pos/res)*2-1 regardless.

And display: composer RenderPass(displayScene, quadCam), display shader also outputs position directly. So the "camera" ortho params only matter for screenToWorld mapping (pointer→world). The on-screen visual: world y=0 at screen bottom, increasing upward.

So for pointer→world to match visuals:

• x: world x=0 → clip -1 → NDC -1 → screen left. ✓ matches screenToWorld x = left + (cx/w)*(right-left).
• y: world y=0 → NDC -1 → screen BOTTOM. So screen top (cy=0) = world y = view.y + vh/2, screen bottom (cy=H) = view.y - vh/2.

So screenToWorld should be: y = (view.y + vh/2) - (cy/innerHeight)*vh. With my camera setup (top = view.y - vh/2, bottom = view.y + vh/2), the formula camera.top + (1 - cy/H)*(bottom-top) = view.y - vh/2 + (1-cy/H)*vh → cy=0 → view.y + vh/2 ✓; cy=H → view.y - vh/2 ✓.

So fix: y: camera.top + (1 - cy / innerHeight) * (camera.bottom - camera.top).

Alternatively flip camera top/bottom (top=view.y+vh/2, bottom=view.y-vh/2) and keep formula y=top+(cy/H)*(bottom-top): cy=0 → top = view.y+vh/2 ✓. That works too, but then wheel zoom math uses screenToWorld consistently, and pan uses deltas — both fine. But applyView with top>bottom is the standard ortho setup; projection handles it fine. I'll use this cleaner option: camera.top = view.y + vh/2, camera.bottom = view.y - vh/2. Wait, but does anything else use camera coordinates? brush uniforms center uses world coords from pointer — fine. The initial camera construction OrthographicCamera(0, SIM_W, SIM_H, 0) — top=SIM_H bottom=0, consistent with top>bottom convention. I'll update applyView:

camera.left = view.x - vw/2; camera.right = view.x + vw/2; camera.top = view.y + vh/2; camera.bottom = view.y - vh/2;

And screenToWorld stays: x = left + cx/W*(right-left); y = top + cy/H*(bottom-top) → cy=0 → top = view.y+vh/2 ✓; cy=H → bottom ✓.

12. Pan mode delta: view.x -= (wx - pwx); view.y -= (wy - pwy) — dragging right (wx>pwx) moves view left → content follows pointer. With y fixed by same mapping, dragging down increases wy (since wy at larger cy is smaller... wait: dragging pointer down → cy increases → wy decreases (world y). pwy > wy → wy-pwy negative → view.y += ... hmm I wrote view.y -= (wy - pwy) → view.y increases → view center up → content appears to move... let me just trust the standard "grab the world" logic: after adjusting view by minus the world delta, and re-computing the world position under the cursor, it's consistent as long as screenToWorld is correct. The code recomputes pointer.wx after applyView — that's the standard trick. ✓.

13. BRUSH_FRAG erase mode with alpha: mode 1 outputs color 0, alpha fallstrength, with blending Zero/OneMinusSrcAlpha → dst(1-alpha). trailA is HalfFloat RT with alpha channel — blending applies to all channels: rgb *= (1-alpha), a *= (1-alpha). Fine. But note the trail shader writes alpha=1 always; deposit writes alpha... gl_FragColor alpha 1.0 with blending One/One → alpha accumulates too — doesn't matter since display ignores alpha.

Also careful: erase writes gl_FragColor.rgb = 0 and blendSrc=Zero → src contributes 0; dst scaled by (1-alpha). ✓

14. renderer.setRenderTarget(trailA) inside paintStroke — paints into latest trailA (post-swap). ✓ display uses trailA.texture. ✓

15. Food burst paints into BOTH trailA and trailB so it survives the next swap — smart, keep, but remove needsUpdate line there too. Actually the brushMat blending for food burst: I set mode 0 and One/One. ✓

16. gui.add(params, 'agents', {...}).onChange(v => reseed('random')) — v unused, fine. But params.agents is set by lil-gui to the selected value ✓.

17. if (e.target.closest('.lil-gui')) return; — pointerdown on canvas only; the GUI is not inside canvas so target is always canvas. Harmless.

18. Audio start on every pointerdown until actx created — startAudio guards if (actx) return. But if params.audio false, never starts. If user enables later, next pointerdown starts. ✓. Also addEventListener('pointerdown', ..., {once:false}) — fine.

19. loader warmup: for 12 steps stepSim(1) before first composer render — good, gives initial structure.

20. displayMat colFood uniform new THREE.Color(...FOOD_COL) — THREE.Color(r,g,b) with floats ✓.

21. palette GUI select: setPalette(name) receives string ✓.

22. Trail sense shader: t[species] — GLSL ES 1.0/3.0? GPUComputationRenderer uses raw WebGL1-style shaders by default (three compiles as GLSL1 unless WebGL2 → GLSL3? Three r160 always uses WebGL2 and compiles ShaderMaterial GLSL as ES 3.0 with automatic conversions for texture2D etc. For raw variable indexing t[species] where species is a non-const int — in GLSL ES 3.0, indexing a vector with a dynamic integer is allowed ✓. And texture2D gets converted to texture() by three's preprocessor? For ShaderMaterial in WebGL2, three injects #define texture2D texture when GLSL3? Actually three.js WebGL2 + ShaderMaterial: shaders are compiled as GLSL ES 3.00 with compatibility defines including texture2D → texture. Yes (three handles it). GPUComputationRenderer shaders also go through the same material pipeline ✓ (it creates ShaderMaterial internally). The existing demos (004-fluid-dynamics) used GPUComputationRenderer similarly.

But if (i != species) inside a for loop with int — fine in ES3.

One risk: float own = t[species]; — dynamic indexing of vec3 by int — allowed in ES 3.00 ✓.

23. texturePosition uniform name: gpuCompute.addVariable('texturePosition', ...) → sampler uniform named texturePosition automatically in the variable's material. In AGENT_FRAG I reference texture2D(texturePosition, uv) ✓ and in DEPOSIT_VERT I declared uniform sampler2D texturePosition and set uniforms.texturePosition manually ✓.

24. Deposit frag for spore species 3 writes 0.33 to all channels — but fillInitialAgents only assigns species 0..2 (sp = (Math.random()*3)|0). Species 3 never occurs in agents. The sense() has a branch for species==3 — dead code, harmless. The brush 'food' writes white directly to trail. OK. Could remove dead branch but harmless.

25. stepSim deposit: renders depositScene with quadCam — Points with frustumCulled=false ✓.

26. renderer.autoClear toggle during deposit: I set autoClear=false, render into trailA, restore. ✓ But note composer.render() at the end — RenderPass sets its own clear behavior. ✓

27. HalfFloatType RT with LinearFilter — requires OES_texture_half_float_linear (WebGL2: half-float linear filtering is core? In WebGL2, RGBA16F is color-renderable only with EXT_color_buffer_float, and linear filtering of half floats is core (OES_texture_half_float_linear equivalent is core in WebGL2? Actually in WebGL2, float16 textures support linear filtering natively — yes, HALF_FLOAT textures are filterable in WebGL2 core). Renderable requires EXT_color_buffer_float — widely available; three r160 WebGLRenderer requires WebGL2. ✓

28. quadGeo = PlaneGeometry(2,2) shared across trailScene, brushScene, displayScene meshes — sharing geometry across meshes/scenes is fine.

29. reseed() leftover const size unused — remove.

30. loadMsg used ✓; fps in stats ✓.

31. Snapshot: composer.render() then toDataURL — WebGLRenderer default preserveDrawingBuffer:false; toDataURL right after render in same synchronous block works ✓.

32. Wheel listener on dom with passive:false + preventDefault ✓.

33. params.brushSpecies === 4 pan mode in brush GUI: 'pan view': 4 ✓; paintStroke guard params.brushSpecies !== 4 ✓. But erase (right-drag) still works in pan mode — fine.

34. In paintStroke: const pal = PALETTES[params.palette].map(...) — creates colors every stroke; fine perf-wise (pointer events only).

35. lil-gui gui.add(params,'agents', {...}) — object option maps labels→values ✓.

36. composer.addPass(new OutputPass()) ✓ r160.

37. finalPass.uniforms.time — ShaderPass(FinalShader) clones uniforms via UniformsUtils.clone — uniforms accessible via finalPass.uniforms ✓.

38. One more: brushMat initial blending: CustomBlending with blendSrc One / blendDst One; also should set blendEquation AddEquation explicitly (default is AddEquation) ✓. And after erase changes blendSrc/Dst, switching back sets them again in paintStroke ✓.

39. Missing blendSrcAlpha/etc — defaults fine.

40. depositMat CustomBlending Add One One — set explicitly ✓.

41. gpuCompute.dispose() — need to verify existence in r160. Let me check via downloading GPUComputationRenderer.js from jsdelivr.

42. Also in buildAgents on rebuild: depositScene.remove(depositMesh) then create new — also should dispose depositMat. Minor; add dispose.

43. renderer.getClearColor(new THREE.Color()) returns target ✓ r160 signature getClearColor(target) — required.

44. Potential issue: Object.assign(posVar.material.uniforms, {...}) — the variable material already has uniforms: { texturePosition:... }? addVariable creates material with the shader; the sampler uniform is declared in shader and three auto-populates on compile. Object.assign adds ours ✓. Standard pattern from three examples ✓.

45. u.resolution.value for agent compute: Vector2(SIM_W,SIM_H) — used as world bounds AND trail sample normalization ✓ (trail RT is SIM_W×SIM_H).

But WAIT — the agent texture is size×size (e.g., 512×512) but AGENT_FRAG uses resolution uniform for BOTH gl_FragCoord normalization (uv = gl_FragCoord.xy / resolution.xy — this would be wrong: gl_FragCoord spans the agent texture size (512), not SIM_W!).

CRITICAL BUG: In AGENT_FRAG: vec2 uv = gl_FragCoord.xy / resolution.xy; — resolution is the world size (SIM_W×SIM_H e.g. 1440×810), but gl_FragCoord during compute spans the agent texture (512×512). The uv for reading texturePosition must be gl_FragCoord.xy / agentTexSize. GPUComputationRenderer provides... in three examples they pass resolution as texture size? In GPUComputationRenderer examples (e.g., webgl_gpgpu_birds), the shader uses vec2 uv = gl_FragCoord.xy / resolution.xy; and the material has uniform resolution set to... Actually GPUComputationRenderer defines a uniform automatically? No — examples define their own. In the birds example: fragmentShaderPosition uses uniform vec2 resolution;? Hmm, no. Let me recall the birds GLSL:

Hmm, actually GPUComputationRenderer automatically adds a resolution uniform to compute materials! Let me check the source: In GPUComputationRenderer.addVariable, it creates material with uniforms including... I remember the pass-through and the resolution: createShaderMaterial — and there's a line: variable.material.uniforms.resolution = ... not sure.

From three.js GPUComputationRenderer source (r160):

and createShaderMaterial:

and addResolutionDefine:

So resolution is a #define (vec2 of the compute texture size) injected into every compute material. My AGENT_FRAG declares uniform vec2 resolution; via the TORUS chunk → CONFLICT: #define resolution vec2(...) plus uniform vec2 resolution; → the define would replace the identifier in the uniform declaration → compile error or weird behavior.

So I MUST NOT declare uniform vec2 resolution in AGENT_FRAG. The define gives me the agent texture size as resolution. For the world size I need a separate uniform, e.g. worldSize. And gl_FragCoord.xy / resolution gives correct uv for the agent texture ✓ (that's why the define exists).

For the OTHER ShaderMaterials I create directly (trailMat, brushMat, displayMat), there's no injected define, so my uniform vec2 resolution is fine there. But TORUS chunk is used by AGENT_FRAG and TRAIL_FRAG. TRAIL_FRAG: gl_FragCoord spans SIM_W×SIM_H and resolution uniform = (SIM_W,SIM_H) ✓ correct there. In AGENT_FRAG, TORUS's wrapPos uses resolution as world size — WRONG semantics: positions are in world units (SIM_W×SIM_H) but resolution define is (512,512).

Fix AGENT_FRAG:

• Remove ${TORUS} include; instead:

So replace resolution with worldSize everywhere in AGENT_FRAG except the uv computation. And add uniform worldSize to posVar uniforms.

Let me rewrite AGENT_FRAG accordingly:

resolution define available ✓.

Also DEPOSIT_VERT uses uniform vec2 resolution (world size) — that's my own ShaderMaterial, no define conflict, but naming: resolution uniform = (SIM_W,SIM_H) ✓ works. Fine.

BRUSH_FRAG_FULL: declares uniform vec2 resolution via... wait BRUSH_FRAG declares uniform vec2 resolution; explicitly ✓ (not via TORUS). brushMat uniforms include resolution ✓.

TRAIL_FRAG uses TORUS (declares uniform vec2 resolution) and trailMat provides it ✓. TRAIL_FRAG uv = gl_FragCoord.xy / resolution — gl_FragCoord spans SIM_W×SIM_H = resolution ✓. But TORUS's wrapPos/torusDelta are unused in TRAIL_FRAG — just the declaration. Fine.

Wait — TRAIL_FRAG blur taps use uv + px offsets — at edges it samples across the edge WITHOUT wrap (uv out of [0,1]... the RT has RepeatWrapping ✓ set wrapS/T Repeat → taps wrap nicely ✓.

46. Another check: in AGENT_FRAG I sample texturePosition — the variable's own texture ✓ dependency set ✓.

47. hash12(uv * 913.7 + fract(time)*71.3) — fine.

48. GPUComputationRenderer default texture type: In r160, createTexture uses FloatType by default? Let me verify: this.createTexture = function () { ... return new DataTexture( data, sizeX, sizeY, RGBAFormat, FloatType ); } — yes FloatType. Positions in world units up to 1440 — Float32 fine ✓.

49. The compute renderer in newer three needs renderer passed in constructor — I pass it ✓.

50. Also posVar.material.uniforms Object.assign — add worldSize instead of resolution. Remove resolution from agent uniforms (would be shadowed by define anyway... actually the define replaces token resolution in shader source, including uniform vec2 resolution; → becomes uniform vec2 vec2(512.0,512.0); → syntax error. MUST remove the TORUS include from AGENT_FRAG.)

51. sense() function: species==3 branch — dead but keep.

52. Also depositScene/depositMesh render: renderer.render(depositScene, quadCam) — depositMat uniforms.texturePosition set each step ✓; also set depositMat.uniforms.resolution already at build (SIM_W,SIM_H) ✓.

53. On resize: sim/trail sizes stay constant; view adjusts ✓ (documented behavior).

54. lil-gui brush 'pan view' + wheel zoom — good.

55. brushMat.uniforms.center in world coords; BRUSH_FRAG uses gl_FragCoord.xy in RT pixel coords (0..SIM_W/H) — world == RT pixels ✓ (world units ARE sim pixels).

56. In paintStroke, steps based on brushSize — smooth strokes ✓.

Now also verify GPUComputationRenderer.dispose exists in r160. Let me fetch the file and grep. Also check renderer.getClearColor(target) requirement.

Also one more potential issue: renderer.autoClear = false then render depositScene into trailA — but the composer's RenderPass at the end: composer.render() uses autoClear? RenderPass sets renderer.autoClear = false internally? RenderPass has clear property; EffectComposer handles. Standard setup from examples ✓.

Also: warm-up calls stepSim(1) × 12 before animate — trailMap uniform etc fine.

Also in reseed, params.agents might be a string? lil-gui with object options sets the value from the object's values (numbers here) ✓.

One more: sim.add(params,'sensorAngle',5,90,1) etc ✓.

Audio: setInterval chord advance even when tab hidden — fine.

addEventListener('pointerdown', () => { if (params.audio) startAudio(); }) — global; also fires when clicking GUI — starts audio on GUI interaction too; acceptable (user gesture).

Also dom.setPointerCapture(e.pointerId) — pointermove continues outside window ✓; pointerup on window ✓.

57. fillInitialAgents 'colonies': SIM_H * 0.26 vs SIM_W*0.26 mix — fine.

58. Ring mode heading tangent → ring rotates ✓.

59. In stepSim, u.dt.value = dt where dt=frac (simSpeed/sub). With simSpeed up to 3 → sub up to 3 ✓. moveSpeeddt etc ✓. turnSpeeddt ✓.

60. Sense uses sensorDist in world px ✓.

Edge case: params.agents non-perfect-square like 262144 = 512² ✓, 131072 = 512×256 → size=ceil(sqrt)=362.04→363? sqrt(131072)=362.04 → size 363 → 131,793 slots; extra agents beyond count get filled anyway by fillInitialAgents (fills ALL size² slots). I always fill the entire texture regardless of params.agents — so actual agent count = size² ≥ requested. For 131072 → 363²=131,793 (~132k). Label says 128k — close enough. Stats show params.agents/1000 — slight mismatch; better to compute actual. I'll store agentCount = size*size and display that.

Fix in buildAgents: params._actualAgents = size*size? params shown in GUI... better use a module variable actualAgents. Update stats to use it. And reseed uses params.agents as count → buildAgents computes size ✓.

61. depositScene.remove(depositMesh); agentGeom.dispose(); — also dispose depositMesh.material. Add.

62. gpuCompute.dispose() — check existence. If not exists in r160, guard: if (gpuCompute.dispose) gpuCompute.dispose(). Actually I recall GPUComputationRenderer got dispose() in r15x. Let me verify by fetching source.

63. view.zoom initial fit — whole garden visible ✓.

Also let me double check screenToWorld after the camera Y fix and the wheel zoom math: zoom about cursor: w0 = world under cursor before; applyView; w1 after; adjust view by (w0-w1) ✓ standard.

Also HUD hint says right-drag erase — brushMat erase uses button===2 ✓ (pointer.button from pointerdown persists during move ✓).

Touch: pointerdown button 0 → paint ✓; two-finger not handled — fine.

Now fix list for part2/part3/part4:

• part2: rewrite AGENT_FRAG (remove TORUS include, use worldSize uniform; keep resolution define usage for uv).
• part3: applyView Y flip fix (top = view.y + vh/2, bottom = view.y - vh/2). Also initial camera OrthographicCamera(0, SIM_W, SIM_H, 0) is fine (top>bottom). buildAgents: add worldSize uniform instead of resolution; track actualAgents; dispose material; guard gpuCompute.dispose. screenToWorld unchanged (works with top>bottom now). Remove unused const size in reseed.
• part4: remove brushMat.needsUpdate = true (two places); stats uses actualAgents.

Wait — one more thing about the camera Y: initial camera = new OrthographicCamera(0, SIM_W, SIM_H, 0, -1, 1) then applyView overrides. Fine.

But hold on — with camera.top = view.y + vh/2 and bottom = view.y - vh/2, the deposit pass: deposit shader ignores camera (raw clip). Display ignores camera. Brush ignores camera. So the camera ONLY matters for pointer math. ✓ And quadCam is a separate fixed ortho (-1..1) — actually irrelevant too since all shaders write gl_Position directly. Fine.

Also should double check three's ShaderMaterial in WebGL2 accepts texture2D calls — yes, three prepends #define texture2D texture for GLSL3 conversion... Actually for WebGL2, three's WebGLProgram prefixes fragment shaders with:

when using ShaderMaterial? Yes — three converts GLSL1-style shaders automatically (it defines texture2D, textureCube, etc. for ES3). ✓ All existing demos rely on this.

GLSL dynamic vec3 indexing t[species]: ES 3.00 allows indexing vectors with dynamic indices? Vector indexing with a non-constant integral expression — allowed in ES 3.0 (vectors can be indexed with any integer expression). ✓

Also int species = int(floor(a.w + 0.5)); ✓. In DEPOSIT_FRAG same pattern ✓.

Let me now verify GPUComputationRenderer.dispose in r160 — fetch source. Then apply fixes with replace operations on the part files, re-assemble, re-check syntax, deploy, update index page.

Confirmed:

1. GPUComputationRenderer defines resolution as vec2(sizeX, sizeY) (compute texture size) — my TORUS chunk's uniform vec2 resolution in AGENT_FRAG would conflict. Must fix.
2. dispose() exists ✓.
3. createTexture uses FloatType RGBA ✓.

Now apply fixes to part2 (AGENT_FRAG), part3 (camera Y, worldSize uniform, actualAgents, dispose), part4 (remove needsUpdate, stats actualAgents).

Fix 1 — part2 AGENT_FRAG rewrite. Replace the whole AGENT_FRAG block:

with a version without TORUS, using worldSize uniform, and resolution (the injected define) only for agent-texture uv.

Also TORUS chunk is still used by TRAIL_FRAG (which has its own resolution uniform ✓) and defines wrapPos/torusDelta — TRAIL_FRAG doesn't use wrapPos... it only declares uniform vec2 resolution which trailMat provides. Fine, keep TORUS for TRAIL_FRAG.

Now fix part3:

1. applyView Y flip: top = view.y + vh/2, bottom = view.y - vh/2.
2. posVar uniforms: replace resolution: { value: new THREE.Vector2(SIM_W, SIM_H) } with worldSize: {...}.
3. buildAgents: track actualAgents (module-level), dispose deposit material on rebuild.
4. reseed: remove unused const size line.

Now fix buildAgents: track actualAgents, dispose old material properly, and the reseed leftover. Let me look at the current buildAgents block:

Add let actualAgents = 0; there. And in buildAgents:

→ add material dispose + set actualAgents = sizesize at end. The return statement returns sizesize — set actualAgents there.

reseed:

→ remove the unused line.

**************************************************************************************************************************************************************************ts.

********************************************************************************************************************************************ne.

Syntax OK. Now do a final consistency review of the full assembled file — quickly grep for the key identifiers to make sure everything is wired (worldSize, applyView, actualAgents, no leftover needsUpdate, no TORUS in AGENT_FRAG, screenToWorld). Then deploy to /space/demos/011-physarum-garden/index.html and update the main index.

All checks pass:

• needsUpdate: 0 occurrences ✓
• worldSize wired in shader + uniforms ✓
• actualAgents tracked and displayed ✓
• uniform vec2 resolution only in TORUS (173, used by TRAIL_FRAG), DEPOSIT_VERT (255), BRUSH_FRAG (284) — all my own materials, no conflict ✓
• AGENT_FRAG has no TORUS/resolution-uniform ✓
• screenToWorld present ✓

Wait — line 173 is TORUS chunk which is only included in TRAIL_FRAG now. Let me double check TORUS is still referenced by TRAIL_FRAG (it declares resolution used for uv normalization) ✓ (grep showed TRAIL_FRAG still has ${TORUS}? I didn't remove it — only AGENT_FRAG was rewritten. ✓)

One more check: screenToWorld formula — with camera.top = view.y + vh/2 > camera.bottom, formula y = camera.top + (cy/H)*(bottom - top): cy=0 → top (world high Y) at screen top ✓ matches visuals.

Deploy now: copy to /space/demos/011-physarum-garden/index.html, then update /space/demos/index.html inserting a new card at the top of the demo list (after the "" comment).

*******************************************************************************************************************************************************************************************************************************nt.

The comment line has 8 spaces before it, and the anchor 10 spaces. My search had 8 spaces for the comment but the actual line is <!-- New demos are added here --> — wait, sed shows <!-- New demos... with 8 spaces? cat -A shows: <!-- New demos are added here -->$ — 8 spaces. And my search string started with 8 spaces for the comment... Actually in my replace call, I wrote <!-- New demos are added here -->\n <a class=.... The mismatch may be due to the num span format: existing cards use <span class="num">010</span> not "Demo 010". But that part wasn't in my search text... My search was two lines: comment line + anchor line. The anchor line in file: <a class="demo-card" href="./010-abyssal-bloom/index.html"> (10 spaces). My search had 10 spaces too. Hmm, maybe my comment line had different spacing — in the replace call I typed 8 spaces. Let me just do a simpler single-line replace anchored on the anchor line only.

Still no match. There may be trailing whitespace or different line endings. cat -A showed <a class="demo-card" href="./010-abyssal-bloom/index.html">$ — no trailing spaces, ends with $. And <span class="num">010</span>$. Hmm, but the replace tool says not found. Maybe there's \r (carriage return)? cat -A would show ^M for \r — it didn't. Maybe the file changed between reads (s3fs caching)? Let me check the exact bytes with grep -P or od. Or maybe indentation is actually different — sed showed 10 spaces before <a. Let me count precisely: <a class=\"demo-card\" — in cat -A output: " <a class="demo-card" href="./010-abyssal-bloom/index.html">$" — I count 10 spaces. And span line: 12 spaces. That matches my search...

Wait — maybe the issue is the two lines aren't adjacent? Line 100 is the anchor, line 101 the span. They appear adjacent in sed output (lines 100-101 shown). Hmm.

Could there be a hidden character? Let me od the region or use grep -c to count the anchor line alone. Maybe quotes are different (e.g., ")? No, cat -A shows plain quotes.

Let me try replacing just the single anchor line without the span line.

Interesting — the od output reveals: line 100 <a class="demo-card" ... — count the spaces: after \n there are 10 spaces then <a. od shows: \n < a — that's positions: \n then 10 spaces? od -c each char: after \n at 0000055ish, spaces... hard to count exactly but cat -A showed 10. My search string used 10 spaces. Hmm wait, actually looking at od: \n then — between \n and <a I see what appears to be 10 spaces (od columns are tricky). Then the anchor text matches exactly.

Wait, maybe the issue: my search string had \n between the two lines, plus 12 spaces before <span. od shows \n then spaces then <span class="num">010</span>. That all matches...

Unless the replace tool has an issue with the file being on s3fs, or my search contained a subtle difference: I typed href="./010-abyssal-bloom/index.html"> — matches. <span class="num">010</span> — matches.

Hmm, wait — maybe my search text had 10 spaces but the file has... let me count from od: bytes 0000053-0000057: > \n then spaces start at some offset. od line 0000040 e r e - - > \n — this row covers 16 bytes: e,r,e,space,-,-,>,\n,space,space,space,space,space,space,space,space (8 spaces). Next row 0000060: < a ... hmm od -c rows are 16 bytes. Row 0000040 (octal offset 32): bytes 32-47: e r e ' ' - - > \n ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' — that's 8 spaces at end (bytes 40-47). Row 0000060 (octal 48): bytes 48-63: ' ' ' ' < a ' ' c l a s s = " d e m o - c — 2 more spaces then <a at byte 50. So total 8+2 = 10 spaces. ✓ matches my search.

So why did the tool fail? Possibly the tool normalizes or the s3fs read is stale? Or maybe... my first replace attempt also failed identically. Both times "search text not found".

Maybe the issue: the replace tool reads the file fresh, and the file might have CRLF? No, od shows \n only.

Hmm, let me try a different approach: use sed/python in shell to do the insertion. Python is more reliable here.

Card inserted at the top of the list. Now final verification:

1. Verify the deployed demo file is intact (wc, tail).
2. Maybe do a headless render test? No browser available presumably. At least verify CDN URLs resolve (import map URLs).
3. Then finish.

Let me do a final sanity check: verify the deployed file tail, verify CDN reachability quickly (three module, lil-gui), and confirm the closing tags exist.

Everything is deployed and verified:

• /space/demos/011-physarum-garden/index.html: 35,838 bytes, proper closing tags, syntax-validated module script
• /space/demos/index.html: updated with card 011 at top
• All CDN URLs return 200

One more prudent check: run a quick headless smoke test if a browser is available? Probably not in this environment. Let me check quickly if chromium/puppeteer exists — if not, skip. Actually, time budget: I've used ~50%+ already. The code was carefully reviewed for GLSL/three.js correctness. Let me do one more targeted self-review of the trickiest remaining bits by reading the final file's stepSim + animate once more to be safe, then finish.

Actually, let me do a fast grep-based review of the full deployed file for a couple of specific remaining concerns:

1. In stepSim, u.trailMap.value = trailA.texture — set every step ✓.
2. In animate, display uses trailA after swaps ✓.
3. params.brushSpecies === 4 pan: in pointermove, when panning, view.x -= (wx-pwx) — with the corrected Y mapping, wy decreases as you drag down; view.y -= (wy - pwy) → view.y increases → content moves down with the pointer ✓ correct grab behavior.
4. The wheel zoom handler: uses screenToWorld before/after — ✓.

One more possible issue: in paintStroke, pal computed each call from palette — fine.

And in the agent sense shader, food = min(t.r, min(t.g, t.b)) — food painted white contributes equally to all channels, so min detects it ✓. Species overlap also creates min>0, mild food-like attraction at crossings — acceptable organic behavior.

Also deposit for food: brush food paints directly into trail ✓.

Everything looks good. One last check — make sure there's no leftover TORUS unused warning issue: TORUS chunk is included in TRAIL_FRAG ✓ (grep line 173 was TORUS's uniform vec2 resolution;, and TRAIL_FRAG includes ${TORUS}). TRAIL_FRAG uses resolution for uv normalization ✓ and trailMat provides the uniform ✓. wrapPos/torusDelta in TRAIL_FRAG are unused — GLSL compilers warn but don't error on unused functions... Actually unused functions are fine.

DEPOSIT_VERT (255) and BRUSH_FRAG (284) declare their own resolution uniforms with values provided ✓.

I'm confident. Done — call _success.