Create Abyssal Bloom Demo

The task is "Wake up and do as you please." Given my purpose is to create cool Three.js demos in /space/demos/, I should create a new advanced demo.

Let me first check the current state of the demos folder to see what's there and what number to use next.

Let me check the current state of the demos folder.

The demos folder has 9 demos so far. I need to create a new demo (010). Let me look at the index.html listing to see the demo list and descriptions, so I can create something that doesn't duplicate existing themes.

Existing demos:

1. 001-spinning-cube
2. 002-nebula-galaxy
3. 003-mandelbulb-explorer
4. 004-fluid-dynamics
5. 005-gravity-sandbox
6. 006-event-horizon
7. 007-sonic-reactor
8. 008-void-runner
9. 009-azure-odyssey (sailing demo)

Let me see the full index to understand the descriptions of each.

I have 9 demos. Time to create demo 010. Let me brainstorm a fresh concept that doesn't overlap with existing demos:

1. Spinning cube (basic)
2. Nebula galaxy (particles)
3. Mandelbulb explorer (raymarched fractal)
4. Fluid dynamics (GPU Navier-Stokes)
5. Gravity sandbox (N-body)
6. Event horizon (black hole lensing)
7. Sonic reactor (audio visualizer)
8. Void runner (endless runner game)
9. Azure odyssey (sailing sim)

New ideas for 010:

• Terrain/ecosystem: procedural planet with erosion... somewhat overlaps with sailing terrain.
• Cloth/soft body physics sim with verlet integration — interactive cloth, tearing, wind. Could be cool: "Cloth Playground" — but maybe a bit plain.
• Voxel-based destructible terrain game.
• A ray-marched volumetric clouds / weather sim — fly through volumetric clouds. Advanced and gorgeous.
• Fireworks show with physics particles + audio pops.
• Interactive DNA/protein viz — meh.
• Asteroid mining / space shooter game — overlaps with void runner somewhat (both space).
• "Neon Tokyo rain" — a rainy cyberpunk city street scene with volumetric fog, wet reflections, rain particles, lightning. Very atmospheric.
• Solar system / planetary simulation — overlaps gravity sandbox.
• Kaleidoscope / reaction-diffusion — reaction-diffusion (Gray-Scott) GPU simulation displayed on 3D surface! That's visually stunning and distinct. Turing patterns on a sphere/torus, feeding mouse input.
• Boids flocking — GPU flocking with thousands of boids, predator-prey interaction, formation. That's a classic wow demo. Combined with an underwater scene: "Neon Abyss" — deep sea with bioluminescent jellyfish boids? A deep sea scene with GPU-flocked lantern fish, volumetric god rays, procedural jellyfish with tentacle physics... that's gorgeous and distinct.

Let me pick: "Abyssal Bloom" — a deep-sea scene:

• GPU flocking (boids) of thousands of bioluminescent fish (lantern fish) implemented with GPGPU (float textures for position/velocity, fragment shader updates) — rendered as instanced fish meshes with glow.
• Procedural jellyfish: bell mesh with vertex shader pulsing, tentacles as animated lines/curves, drifting around, bloom glow.
• Volumetric-ish god rays: light shafts from above (billboarded planes with additive shader or fake volumetric cones with fbm noise).
• Particulate "marine snow" drifting.
• Terrain seabed with fog.
• Interactive: mouse click emits a "lure" light that attracts fish; or press to scare them. Camera orbit.
• Post-processing: bloom, vignette. Fog for depth.
• Audio ambience: deep sea hum (synthesized), optional.
• HUD + GUI controls: fish count, cohesion/separation/alignment weights, lure strength, jellyfish count, etc.

That's a strong, distinct, advanced demo: GPGPU boids + procedural jellyfish + fake volumetrics + marine snow + bloom.

Alternatively a Gray-Scott reaction-diffusion demo. But jellyfish + boids deep sea is more "wow" and 3D.

Let me go with "Abyssal Bloom" (demo 010).

Key technical design:

GPGPU Boids

Use THREE's GPUComputationRenderer from examples (addons/misc/GPUComputationRenderer.js). With import map:

• Texture size: e.g. 64x64 = 4096 fish, or 128x128 = 16384. Let's do configurable up to 16k.
• Position texture: xyz pos + w maybe unused. Velocity texture: xyz vel.
• Update shaders: classic boids rules — for each boid, loop over neighbors... that's O(N²) which is too much for 16k. Common approach: sample a subset of random neighbors (e.g., 16-32 samples) — "stochastic boids". Works well enough visually. Alternatively use spatial hashing — too complex for a demo. I'll do stochastic sampling: each boid samples K random others via hash of its index and frame, accumulates alignment/cohesion/separation from those. With K=24 and 4096 boids, that's fine.

Additional forces:

• attraction to lure (mouse-controlled point light that fish follow) when active
• avoidance of jellyfish bodies? Could add avoidance of a few jelly positions passed as uniforms.
• boundary containment: soft sphere/box bounds steering
• wander noise
• predator scare: click to pulse scare — fish flee from point.

Fish rendering: InstancedMesh with a fish-like geometry (cone-ish elongated body + tail fin). Per-instance orientation from velocity: build rotation matrix in vertex shader using velocity attribute... For InstancedMesh, we can pass per-instance data via instanced BufferAttributes reading from GPGPU textures. Standard technique: use positionVariable.texture in vertex shader via texture2D fetch using uv from instance index. Use onBeforeCompile or fully custom ShaderMaterial. I'll write a custom ShaderMaterial for the fish: attributes = position/normal/uv of base geometry + instance uv (reference). Then fetch pos & vel from textures, orient geometry by basis built from velocity, apply tail wiggle (vertex shader: bend by sin(time + phase) weighted by |x| along body), glow color by instance hue variation.

Lighting: fake — glow shader with fresnel rim, plus simple lambert from "moon" light above. Actually deep sea: fake it with emissive gradient; bloom will make them pop.

Jellyfish

Procedural generation: N jellyfish (e.g., 7), each a THREE.Group:

• Bell: sphere geometry squashed, custom shader: fresnel translucent glow, pulsing scale (vertex shader contraction), inner organ glow.
• Tentacles: use THREE.Line or thin cylinders? For beauty: use ribbons — but lines with additive blending and vertex shader sine sway are cheap and look great with bloom. Each jelly has ~12 tentacles, each a line strip of ~24 segments, animated in vertex shader with phase offsets; or animate on CPU per frame (7 jellies × 12 tentacles × 24 segments = ~2000 points, trivial). GPU better: static geometry with per-vertex "segment index" attribute, vertex shader displaces with sine chains. I'll do GPU animation via custom shader with uniforms (time, phase per jelly via attribute).

Jelly movement: CPU — slow drift, sinusoidal bobbing, bell pulse syncs with propulsion: contract bell → move up. Wander within bounds. Pass jelly positions to boids shader as uniform array for avoidance.

Light shafts (god rays)

Fake volumetric: several large planes/cones from surface with additive shader using fbm noise scrolling, faded by depth. Place ~10 shafts, slowly swaying. Plus a "surface" glow plane far above with caustics-ish shader? The camera is underwater; looking up should show a bright water surface: a big plane at y=+60 with animated caustic shader (voronoi-ish), additive.

Marine snow

Points (2-3k) drifting down slowly with sway, wrapping in a box around camera. Simple Points shader with soft round sprites, size attenuation, slight twinkle.

Seabed

Simple dark terrain: plane with noise displacement, dark blue-green, fog does most of the work. Add some rocks (icosahedrons scattered), maybe glowing coral-ish dots? Keep simple: rocks + a few glowing "anemone" points. Actually maybe skip terrain; deep sea mid-water is fine, but a floor grounds the scene. Include a gently undulating floor with fog + a few rock formations.

Post-processing

EffectComposer + RenderPass + UnrealBloomPass + Vignette (custom shader pass) + optional film grain. OutputPass for color space in r160.

Interaction / GUI / HUD

• lil-gui via CDN (import from unpkg: three/addons/libs/lil-gui.module.min.js).
• Controls: boid count (rebuild), cohesion/alignment/separation weights, max speed, lure attraction, bloom strength, fog density, jellyfish count, pause, snapshot PNG.
• Mouse: move a lure light (raycast to a plane at camera focus depth or just project to sphere around center). Hold mouse / press to attract fish to lure. Click "pulse" to scare? Let's define: pointer move moves lure; holding pointer activates attraction; pressing space triggers "sonar pulse" that scares fish outward and makes jellies flash.
• OrbitControls for camera + auto-orbit toggle.
• HUD: FPS, fish count, mode hints.

Audio (optional)

Synthesized deep-sea ambience: low drone (detuned oscillators through lowpass), slow LFO, occasional "whale call" (sine sweep with vibrato + reverb-ish via delay), bubbles (filtered noise pings). Toggle button. Keep modest. Sonic Reactor already did audio, but ambience adds to immersion. I'll include a compact ambience engine with mute toggle.

Let me be careful about scope — the file will be big (~1200-1500 lines). That's fine.

Let me now check three.js version 0.160.0 addons paths to be sure:

• three/addons/controls/OrbitControls.js
• three/addons/postprocessing/EffectComposer.js
• three/addons/postprocessing/RenderPass.js
• three/addons/postprocessing/UnrealBloomPass.js
• three/addons/postprocessing/ShaderPass.js
• three/addons/postprocessing/OutputPass.js
• three/addons/misc/GPUComputationRenderer.js
• three/addons/libs/lil-gui.module.min.js

All exist in r160. Good. GPUComputationRenderer in r160 — yes, examples/jsm/misc/GPUComputationRenderer.js.

Let me verify GPUComputationRenderer API:

Yes.

Important: for WebGL2 float textures — GPUComputationRenderer uses THREE.DataTexture with float type; rendering to float targets requires EXT_color_buffer_float, widely supported on WebGL2. Good.

Fish rendering with custom ShaderMaterial as InstancedBufferGeometry:

• Create base geometry: a fish built from a stretched cone + tail. Simpler: craft a low-poly fish via merging a few shapes manually as BufferGeometry... Simplest robust approach: use a custom parametric fish via LatheGeometry? Lathe gives radially symmetric body (like a fish without tail fins) — then add tail plane via merged geometry. To avoid merge helper, I can construct a single BufferGeometry manually: build vertices for body (rings along x axis with radius profile) + tail quad strip. That's straightforward:

Then tail fin: triangle fan from tail end: two triangles forming a fin in the vertical plane. Add dorsal fin? Keep body + tail fin + dorsal fin triangles. Normals: compute via computeVertexNormals for body; fins double-sided.

Per-instance attributes for InstancedBufferGeometry:

• aRef (vec2): uv into GPGPU textures per instance.
• aPhase (float): random phase for tail wag.
• aHue (float): color variation.

Vertex shader:

• fetch pos = texture2D(texPos, aRef).xyz; vel = texture2D(texVel, aRef).xyz.
• speed = length(vel); forward = normalize(vel); build basis: right = normalize(cross(up, forward)) with fallback; upv = cross(forward, right).
• scale by fishSize (per-instance slight variation from aHue).
• tail wag: rotation/bend — offset z (lateral) by sin(timefreq + phase + xk) * amp * (x normalized tailward). Where geometry x along body from -L/2..L/2. Bend: pos.z += bend.
• world = pos + basis * (scaled geometry pos).
• color: body base color dark blue-silver with emissive photophore dots? Simpler: gradient along body — bright cyan glow near head (like flashlight fish), plus stripe. Use vUv/position x to compute glow intensity in fragment; fresnel rim for silhouette.
• fragment: additive-ish? Use normal blending with emissive color * intensity; bloom picks it up.

For fog: since ShaderMaterial custom, include fog manually: uniform fogColor/fogDensity; compute exp2 fog. I'll add fog support manually.

Jellyfish bell: SphereGeometry(1, 48, 24, half) scaled; shader: uniforms time, phase; vertex: pulse scale radially: r = 1 + 0.18contract(t) where contract = pow(sin(...),...); also vertex y squash. Fragment: fresnel = pow(1 - |dot(N,V)|, 2.5); color mix(baseColor deep purple, glowColor pink/cyan, fresnel + inner glow bands); alpha additive blending, transparent, depthWrite false. Inner core: small glowing sphere with strong emissive color.

Tentacles: per jelly, BufferGeometry with segments: for each tentacle i (12), segments j (28): base position at bell rim angle theta_i, radius 0.8; attribute aSeg = j/J (0 root → 1 tip), aTheta, aPhase. Vertex shader: y extends downward length L * aSeg; sway: x/z offset = sin(timespeed + aSegk + phase)ampaSeg^1.5; also whole tentacle follows bell contraction slightly (radius * pulse). Line strip with additive blending, color gradient from bright root to faint tip, alpha fade at tip. Using THREE.LineSegments? Need line strips — use single geometry with index and draw as LineStrip? Simpler: build as THREE.Line with THREE.LineStrip per tentacle → 12 draw calls per jelly × 7 = 84 draw calls, meh. Better: merge all tentacles of all jellies into ONE geometry and draw as one THREE.LineSegments where consecutive segment pairs are explicit: for each tentacle, for j in 0..J-2: two vertices (j, j+1). One draw call for all tentacles in scene. Attributes include jelly index → we can fetch jelly position from uniform array uJellies[MAXJ] : vec4 (pos.xyz, pulse). Vertex shader computes world pos.

Similarly all bells in one InstancedMesh? Bells have per-jelly color/phase — use instanced geometry with aPhase/aColorMix attributes, one InstancedMesh draw call.

MAXJ = 8 fixed for uniform arrays; GUI jelly count 0..8.

Jelly CPU update: each jelly has state (pos, vel, phase, pulsePhase, hue). Motion: gentle buoyant bobbing: vy = pulse thrust: when contracting (dPulse positive), accelerate up slightly; plus wander steering; avoid bounds; avoid camera? Keep distance from camera a bit. Update uniform array each frame.

Lure: a glowing orb mesh (small sphere + point light? deep sea: one PointLight could light rocks/floor if they use standard material). Floor/rocks use MeshStandardMaterial? Mixing standard materials needs real lights — I'll use fake lighting everywhere (custom shaders) except floor which can use MeshLambertMaterial with a dim blue ambient + point light from lure. Hmm, simpler: floor uses MeshStandardMaterial with fog, lights: ambient + directional dim + lure PointLight. Rocks same material. That's fine and cheap.

Fish avoid jellyfish: in velocity shader, loop MAXJ uniform vec4 uJellies; if dist < R: push away.

Boundary: world is a cylinder-ish region R=55, y in [-28, 25]? Soft steering back inside.

Sonar pulse (space/click): uniform uPulse = vec4(center, startTime); fish flee: force = dir * strength * exp(-dist/20) * decay(t). Implement in vel shader with uniform uPulseTime (time since pulse, -1 if inactive) and uPulsePos. Strength decays with exp(-t*2).

Lure attraction: uniform uLure = vec4(pos, active); force toward lure when active, stronger for closer? Attraction with falloff.

Camera: OrbitControls, target at (0, 0, 0), auto-rotate optional slow. Plus "drift" cinematic mode? Keep orbit + autorotate toggle.

HUD: top-left overlay: title, FPS, hints. Bottom-right: buttons? lil-gui panel covers controls. Add a small "?" hints line. Keep it consistent with previous demos style: dark HUD, monospace.

Snapshot button: render then toDataURL, download link.

Pause toggle.

Performance guard: fps-based auto quality? Skip; provide pixel ratio control.

Now GPGPU boid shader details:

Common uniforms: uTime, uDelta, uBounds (vec3: radius, minY, maxY), uCohesion, uAlignment, uSeparation, uMaxSpeed, uMinSpeed, uLure (vec4), uPulsePos(vec3), uPulseTime(float), uJellies[8] (vec4), uJellyCount(int), uMouseRay? not needed.

Velocity shader:

Deterministic hash sampling means a fish always samples same set — less accurate but stable; combine: hash(i, uv, floor(uTime2)) changes twice per second — decent compromise. I'll do slowly changing sample set: seed = floor(uTime3.0) so resample 3x/sec. Fine.

Radii: cohesion 8, alignment 6, separation 2.5 (scaled to world ~120 across). For 4096 fish in radius-50 sphere, density ~ 4096/523000 ≈ 0.008 per unit³... R_C=8 sphere volume 2144 → ~17 fish expected. OK.

Forces:

Position shader: pos += vel*uDelta; also hard clamp bounds sphere as safety.

Delta time: clamp uDelta ≤ 0.033 to avoid explosions on tab-switch.

Initial positions: random in shell radius 15-45; velocities random directions speed ~3-6.

Fish size: world ~ 1.2-2 units long. Speeds ~ 4-9 units/s. School looks nice.

Texture width: 64 → 4096 fish default; allow 32 (1024), 64, 96 (9216), 128 (16384) via GUI → re-init GPGPU and instanced geometry (dispose old). Rebuild function.

Boid count changes need rebuilding geometry attributes (aRef for each instance). Fine.

Also fish fragment: emissive intensity modulated by speed (faster = brighter) and pulse flash (sonar makes them flash): pass uPulseTime to fish material too — flash = exp(-dist... ) but fish shader doesn't know pulse pos... can pass uniforms same. Compute flash from distance to uPulsePos with exp decay — nice: pulse wave travels: flash = exp(-abs(dist - uPulseTimespeed_wave)k)... Simple: brightness += pulseGlow * exp(-dist0.04)exp(-uPulseTime1.2). Good enough.

Colors: deep palette: bg #020610 → fog. Fish glow cyan (#4fe3ff) with hue variance toward teal/blue/violet. Jellies: magenta/pink/violet/cyan variety. Lure: warm amber — contrast. Light shafts: pale cyan. Caustics surface: teal.

Bloom threshold ~0.55, strength ~0.9, radius 0.6.

Vignette shader pass + slight chromatic? Keep vignette + grain subtle.

Audio: WebAudio — master gain; drone: 2 oscillators (sine 55Hz, 55.5Hz detune) + lowpass 200Hz, slow gain LFO; "whale": every 14-30s random: osc sine sweep 120→70Hz over 2.5s with vibrato LFO and gain envelope, through delay feedback (0.45s, fb 0.35) for space; bubbles: random short bandpass noise blips high freq, quiet. Sonar ping on pulse: sine 880→440 ping with delay echo — satisfying. Toggle button + starts on first user gesture.

Now — HTML structure: full-page canvas, overlay HUD, lil-gui, importmap, module script. Loading overlay minimal.

Snapshot: preserveDrawingBuffer false — must render immediately before toDataURL in same frame; do composer.render() then canvas.toDataURL.

Let me also add keyboard: [Space] sonar pulse, [L] toggle lure hold?, [C] camera auto-orbit, [H] toggle HUD/gui.

Pointer: pointermove → update lure target position: unproject pointer at fixed distance... Better: lure sits on a sphere of radius 30 around origin? Or raycast onto invisible plane through origin facing camera. I'll do: ray from camera through pointer; find point on ray closest to origin, clamp within radius 45 → lure position; smooth-lerp actual lure toward target. Pointer down (hold) → lure active attract; double-click or space → pulse at lure position. Also mobile touch works with pointer events.

Actually let's make: hold pointer = attract fish to lure; release = lure dims (still visible faintly, fish ignore). Space or double-click = sonar pulse from lure.

Jellies flash on pulse too: pass uPulseTime to jelly materials — brighten.

GUI structure (lil-gui):

• School: Fish count (dropdown), Cohesion 0..3, Alignment 0..3, Separation 0..3, Max speed 2..15, Wander 0..2, Lure pull 0..4, Swirl 0..3
• Jellies: Count 0..8, Drift speed 0..2, Tentacle sway 0..2, Bell glow 0..2? maybe just count + sway + glow.
• Environment: Fog density, Bloom strength, Bloom threshold, Light shafts on/off, Marine snow on/off, Caustics on/off? Keep: fog, bloom strength, shafts intensity, snow count? snow toggle.
• Camera: Auto-orbit toggle, orbit speed.
• Misc: Pause, Snapshot, Mute audio.

FPS meter: simple rAF delta EMA shown in HUD.

Now let me write the code. It'll be long; I'll write it in parts to /tmp and concatenate, then node --check the extracted JS? The JS is a module inside HTML — node --check can verify syntax if I extract the script. Previously they concatenated parts and node --check'd the combined file... node --check on HTML wouldn't work; they must have checked the JS or used --check on an html?? Actually node --check on an HTML file would fail... They said "syntax-checked using node --check" — perhaps they extracted script. I'll write the JS as a separate file first, node --check it, then embed into HTML. Actually simpler: write full HTML, extract script content between tags with sed/awk into /tmp/check.mjs, run node --check. The module imports 'three' — node --check only parses, doesn't resolve imports, so fine.

Let me now carefully write the demo.

Plan structure of the JS (module):

Constants:

Noise GLSL chunk (shared): simple hash + value noise for shaders that need it.

State object P for params (bound to GUI):

Renderer setup: antialias true, alpha false; setPixelRatio min(devicePixelRatio, 2); outputColorSpace SRGB; toneMapping ACESFilmic exposure 1.1.

Scene: background color #030714; fog FogExp2(#031025, P.fogDensity) — but custom shaders handle own fog; scene.fog affects standard materials (floor/rocks). Keep them consistent: same color/density; on GUI change update scene.fog.density and custom uniforms.

Camera: fov 60, near 0.1 far 400, pos (28, 10, 34).

Lights (for standard-material meshes): AmbientLight(#1a2b4a, 0.6), DirectionalLight(#3a5f8a, 0.5) from above, lure PointLight(#ffb45e, 0→intensity when active, distance 60, decay 2).

Floor: CircleGeometry(90, 64, ...) displaced with CPU noise (value noise via JS function), MeshStandardMaterial color #0a1626, roughness 1, flatShading. Rocks: ~26 icosahedrons random scale/pos, same material darker #0c1a2e... plus a few emissive "vents"? Keep simple rocks. Also scattered glowing "anemone" dots: instanced small spheres with emissive cyan/pink — cheap and pretty; 120 of them, static, additive? Use MeshBasicMaterial with additive blending, small (0.12-0.3), sits on floor → bloom picks them. Nice touch.

Caustic surface: PlaneGeometry(400,400) at y=38, facing down (rotateX(PI/2)), custom ShaderMaterial additive: voronoi caustics function of x,z,t; fade by distance from center (soft circle), depthWrite false. Intensity moderate. Voronoi caustic: classic 2-layer voronoi min-edge: caustic = pow(1 - (F2-F1), 8)... implement compact voronoi:

Good.

Light shafts: N=9 planes (width 6-14, height 80) positioned randomly within radius 40, tilted slightly, billboard around Y toward camera (on CPU each frame set rotation y = atan2(camX-x, camZ-z)), shader additive: vertical gradient alpha (fade top/bottom), horizontal soft edge falloff, animated fbm streaks scrolling downward slowly; intensity uniform uIntensity=P.shafts; sway with time (shader: x offset by sin). depthWrite false, depthTest true? They should be occluded by rocks rarely; depthTest true fine.

Marine snow: BufferGeometry with N=2600 points in box 160x90x160 around origin; PointsMaterial custom shader: position wraps via mod in shader? CPU wrap easier: each frame? 2600× CPU update fine actually. But GPU wrap: pos = mod(base + velt - cameraBox...) Let me do shader-based: attribute aSeed(4): base xyz + speed. pos.y = mod(base.y - tspeed, height) - height/2 + offsetY; x = base.x + sin(t*0.3+seed)*1.5; z similar. worldPos relative to origin. Fragment: circular soft sprite alpha, faint blue-white, twinkle. Blending additive, size ~ attenuated. Uniform uSnowAlpha toggle.

Snow count GUI: rebuild geometry on change (or max count with drawRange). Use drawRange: create max 4000, setDrawRange(0, P.snow).

Lure: group: core sphere (0.35) MeshBasicMaterial(#ffc37a), halo sprite (additive radial texture generated via canvas), point light. Visible intensity lerp toward active/inactive. Position lerps to target (ray-cast). When active: light intensity 30 (r160 uses physically correct lights? renderer.useLegacyLights default false in r160 → intensity in candela-ish; PointLight intensity 30, distance 70, decay 2 works). Also spawn gentle rising bubbles at lure when active? skip.

Sonar pulse visual: expanding ring sphere: Mesh(SphereGeometry(1), ShaderMaterial fresnel shell additive) scaled over time: r = t*28, alpha fades; plus flash uniforms. Manage simple object {t0, pos}.

Boids GPGPU:

WIDTH from fishCount sqrt. gui options: 1024(32), 4096(64), 9216(96), 16384(128).

buildSchool(count):

• dispose old gpu? GPUComputationRenderer has no dispose of variables — recreate renderer object; dispose render targets via gpu.dispose? There is gpuComputationRenderer.dispose() in newer three; r160 — I think it exists (added ~r15x). I'll guard: if (gpu && gpu.dispose) gpu.dispose().
• create textures, fill.
• velocity shader & position shader strings with uniform refs.
• vars; dependencies; uniforms; init check error console.
• fish geometry: buildFishGeometry() returns BufferGeometry (non-indexed or indexed, with attributes position, normal, aBody (x normalized -1..1 along body), aFin (0 body,1 fin? for color), uv).
• instanced: InstancedBufferGeometry from base: use instancedGeo = new **************************try(); instancedGeo.index = base.index; instancedGeo.attributes.position = ... copy; add aRef (Float32 per instance: (i+0.5)/W, (j+0.5)/H), aPhase, aHue. instanceCount = count.
• ShaderMaterial with uniforms: texPos, texVel (set each frame from gpu.getCurrentRenderTarget), uTime, uSize, fog uniforms, pulse uniforms, colors.
• mesh = new THREE.Mesh(instancedGeo, mat); frustumCulled = false.
• Keep references to dispose on rebuild.

Fish vertex shader:

Fish fragment:

Need vWorldPos varying — pass it.

Emissive levels: bloom threshold 0.5 with ACES tonemap — emissive up to ~2.5 for heads gives nice glow.

Since fish are small and fast, normal-based lighting barely matters; mostly emissive. Good for perf.

Jelly shader (bell instanced):

InstancedBufferGeometry from SphereGeometry(1, 40, 24, 0, 2π, 0, ~0.62π) (dome, open bottom). Wait: bell shape — hemisphere squashed. Sphere with thetaLength 0.55π gives cap; scale y 0.8. Per-instance attributes: aIdx (jelly index float), aHueJ. Uniforms: uTime, uJellies[8] (vec4 pos+pulse), uSway, colors, fog, uGlow, uPulseTime/uPulsePos for flash.

Vertex:

Actually jellyfish propulsion: bell contracts (radius decreases, dome height increases) to push water; then relaxes. So: radius factor = 1.0 - 0.25pulse; y factor = 1.0 + 0.35pulse; rim curls: add slight inward curl at bottom rim by pulse.

I'll compute ny = position.y (unit sphere) in [cos(thetaLen), 1]; edge = 1.0 - smoothstep(...) Let me define float skirt = smoothstep(0.55, 0.33, position.y); (0 above, 1 near rim) then p.xz = 1.0 - 0.28pulse*(0.4+0.6skirt); p.y = 1.0 + 0.30pulse; plus wobble: p.x += sin(uTime1.3+idx2.1+p.y2.0)0.03(1.0-position.y).

World: wp = J.xyz + p * scaleJ (per-jelly size via aSize attr 1.2-2.2).

Fragment: fresnel glow, two-tone color by hue: deep violet → pink rim; inner glow: brighter near top center (uv or position.y) simulating organs; alpha = 0.25 + fresnel*0.75; additive blending, depthWrite false, side DoubleSide.

Tentacles (single LineSegments geometry, all jellies): Attributes per vertex: aJelly (idx), aSeg (0..1 root→tip), aAngle (around bell), aLen (tentacle length 2.2-4.5), aPhaseT, aRad (rim radius 0.55-0.95). Vertex shader:

Fragment for lines: color gradient: bright root → transparent tip: use varying vT; alpha = (1-t)*0.85+0.1; color mix pink→cyan by hue attr. Additive, transparent, depthWrite false. linewidth always 1 — thin; with bloom looks fine. To make tentacles more visible, could render each tentacle twice? Bloom will glow them. OK.

Oral arms: extra 4 shorter thicker "frilly" lines per jelly — same system with different params (len shorter, sway higher, rad small) — just part of tentacle generation with flags. Keep it uniform: 14 strands/jelly, 10 long + 4 short central.

Jelly CPU update:

Avoid fish–jelly collision handled in boid shader using uJellies.

HUD: fixed divs: title "ABYSSAL BLOOM", stats line (fps • fish • draw calls?), hints line: "drag — orbit · move pointer — lure · hold — attract · space / double-click — sonar pulse · H — hide UI". Style monospace, subtle.

Also loading fade-in overlay: "descending..." quick fade 600ms after init.

Failure handling: if WebGL2 float render targets unavailable, show message. GPUComputationRenderer.init() returns error string → display overlay.

Now audio engine (compact):

Start on first pointerdown/keydown (gesture). Mute button in GUI.

Noise buffer: create 2s buffer of white noise.

Whale call: osc type 'sine' freq envelope: 140→90→120 wobble? plus slight overdrive via waveshaper? Keep: two detuned sines + lowpass 400, gain env attack 0.6 release 1.5, freq glide exponential. Through delay. Every 18-35s random.

Bubbles: every 0.4-1.2s: bandpass noise burst freq 800-2400 random, Q 8, gain 0.02-0.05, dur 0.08-0.2s, pan random (StereoPanner). Subtle.

Sonar ping also gets visual tie (called in sonarPulse()).

Snapshot:

Resize handler: camera aspect, renderer size, composer size, bloom resolution auto.

Main loop with clock; clamp dt; update: gpu.compute (if !paused), update jelly CPU (if !paused), uniforms time (always? if paused, keep time frozen for coherence — freeze simTime when paused but still render), lure lerp, shafts billboard, pulse visual, controls.update, HUD fps, composer.render.

paused: skip gpu.compute & jelly update & simTime advance; render still.

Now write shaders carefully to avoid GLSL errors:

• Use texture2D (WebGL2 GLSL1 shaders via three are compiled as GLSL3? No — ShaderMaterial default GLSL1 → texture2D fine; GPUComputationRenderer shaders also GLSL1 style with texture2D).
• Uniform arrays in GLSL1: uniform vec4 uJellies[8]; indexed with non-constant int requires int(aJelly + 0.5) — indexing uniform array with dynamic index is allowed in vertex shaders (GLSL ES: vertex shader can index with any integral constant-index-expression... In GLSL ES 1.0, array indexing must be with constant-index-expression EXCEPT for uniforms in vertex shaders which can use arbitrary indices? Spec: In vertex shaders, indexing of uniform arrays is allowed with any integer expression. In fragment shaders, only constant-index-expressions for sampler arrays; other arrays can be indexed with constant-index expressions... To be safe, tentacle/bell shaders are vertex-shader indexing (fine), boid velocity shader loops with constant bounds (fine).
• In boid shader (fragment shader of computation), I loop for (int i=0;i<8;i++){ if (i >= uJellyCount) break; ... } — dynamic loop bounds not allowed in ES 1.0? Loops must have constant bounds for some strict compilers, but comparing inside/break is allowed. Use constant bound 8 and break — widely used pattern, OK.

GPUComputationRenderer variables' shaders: they're fragment shaders with uniform sampler2D texturePosition; auto-added? The computation renderer passes the variable textures by name given to addVariable. Resolution uniform? It adds uniform vec2 resolution; automatically? Looking at GPUComputationRenderer source: it adds resolution uniform. It prepends common: uniform sampler2D ...? No — it doesn't declare samplers; your shader must declare uniform sampler2D texturePosition; etc. The passThruVertex handles uv varying. Yes: variables' fragment shaders get varying vec2 vUv;? The vertex shader used is:

Let me recall GPUComputationRenderer: it creates material with getPassThroughVertexShader():

and fragment wrapper? No — your fragment shader is used as-is; you compute uv via gl_FragCoord/resolution:

Standard examples (e.g., webgl_gpgpu_birds) write:

and declare uniform vec2 resolution;? In examples they don't declare resolution — GPUComputationRenderer adds it automatically. Check: GPUComputationRenderer.addVariable creates material uniforms including... In the source:

addResolutionDefine adds material.defines.resolution = ...? Let me recall:

Yes — resolution is a #define, not uniform. So in shaders use resolution directly (it's defined). Good — I'll use gl_FragCoord.xy / resolution.

And uniforms for texturePosition/textureVelocity are added automatically by the renderer when rendering each variable (it assigns uniforms[dep.name].value = ...). In examples, they also do velVar.material.uniforms['time'] = {value:...} for custom uniforms. And the sampler uniforms texturePosition etc. exist implicitly — the renderer adds uniforms for dependencies automatically? In examples (gpgpu birds):

Hmm, in the official example webgl_gpgpu_birds (r160) they define:

They add custom uniforms but not the texture ones — GPUComputationRenderer.addVariable does:

and in render: for each dependency: uniforms[ dep.name ] = ...? In init():

Actually in init():

And in compute():

Hmm, but uniforms[dep.name] must exist. In source:

and in addVariable→createShaderMaterial, uniforms passed = {} initially; then in init()? Let me recall the actual r160 source more concretely:

Hmm — I'm fairly sure modern GPUComputationRenderer handles dependency uniforms automatically because the birds example doesn't declare texturePosition: {value:null} anymore... Actually the current birds example DOES include:

and does NOT include texturePosition/textureVelocity. And init() has:

Yes I'm confident that's in init(). Good: I only add my custom uniforms.

One more: compute() sets uniforms[dep.name].value = dep.renderTargets[dep.currentIndex].texture — correct.

Water surface caustics: one draw call additive plane — fine.

Draw calls total: fish(1) + bells(1) + tentacles(1) + floor(1) + rocks(1 instanced) + anemones(1 instanced) + snow(1) + shafts(9-10) + caustics(1) + lure(2) + pulse(1) ≈ 20.

Rocks as InstancedMesh with standard material — instanced standard material fine.

Let me also handle renderer.setAnimationLoop for XR? No XR. Use setAnimationLoop anyway.

HUD fps: compute EMA.

Edge cases:

• lil-gui import: import GUI from 'three/addons/libs/lil-gui.module.min.js'; works with unpkg examples path.
• Mobile: touch-action none on canvas; pointer events unified.

Colors/tonemapping: ACESFilmic + OutputPass handles sRGB. UnrealBloomPass before OutputPass. Vignette pass after bloom, before OutputPass? OutputPass converts to sRGB; do vignette in linear pre-output for correctness — fine.

Now about "fog" color: scene bg #04101f? Deep sea: very dark blue #020813. Fog same color so objects fade into bg. Custom shaders use uFogColor uniform = new THREE.Color(0x020813)... but standard materials + scene.fog use scene.fog color. Set both from P? Add fog color fixed, density adjustable.

Exposure: 1.15.

Bloom: threshold 0.55, strength P.bloom, radius 0.55.

Fish emissive values need to exceed threshold after ACES? Bloom pass operates pre-tonemap on linear HDR values? UnrealBloomPass thresholds on luminance of rendered (linear) values. Emissive 1.5 exceeds 0.55 → glow. Base 0.25 body won't. Good.

One caution: UnrealBloomPass + OutputPass order: RenderPass → Bloom → Vignette → OutputPass. OutputPass does tone mapping + sRGB (it reads renderer.toneMapping). In r160 OutputPass applies ACES based on renderer settings. OK.

Let me now write all the code. I'll write it as a single big HTML in parts to /tmp/abyss/ then concatenate. Let me draft the parts:

Part 1: HTML head, CSS, HUD DOM, importmap, opening script tag, imports, constants, utils (RNG), params P. Part 2: renderer/scene/camera/lights/post, environment (floor, rocks, anemones, caustics, shafts, snow). Part 3: GPGPU boids + fish geometry/material. Part 4: jellyfish (bells instanced + tentacles) + jelly CPU update + lure + pulse visuals. Part 5: audio, input, GUI, HUD, snapshot, resize, main loop, init.

Let me write carefully. I'll aim for correctness on first pass since I can't visually test — node --check for syntax; GLSL correctness by careful review.

Details to double check while writing:

1. SphereGeometry cap: new THREE.SphereGeometry(1, 40, 20, 0, Math.PI*2, 0, Math.PI*0.62) — thetaStart 0 at +Y pole? In three.js, thetaStart is horizontal (around Y) and phiStart is vertical from top. Actually signature: SphereGeometry(radius, widthSegments, heightSegments, phiStart, phiLength, thetaStart, thetaLength) where thetaStart/thetaLength are the VERTICAL angle starting from +Y axis (top). Yes: thetaStart=0 top. So cap with thetaLength 0.62π goes from top down past equator a bit. position.y ranges 1 → cos(0.62π) ≈ -0.34. Good: bell slightly past hemisphere → nice dome with curled rim. skirt factor: smoothstep(0.4, -0.2, position.y) → 0 near top, 1 at rim.

2. InstancedBufferGeometry + Mesh (not InstancedMesh): setting geometry.instanceCount. In r160, InstancedBufferGeometry has .instanceCount property (default Infinity → derived). Set explicitly.

3. For bell instancing I need per-instance aIdx & aHueJ & aScale: attributes on InstancedBufferGeometry with InstancedBufferAttribute.

But wait: with InstancedBufferGeometry and a Mesh, three renders instanced when geometry.isInstancedBufferGeometry — yes WebGLRenderer handles.

4. Bells need depth sorting vs tentacles — additive blending, depthWrite false → order among transparent objects by distance; minor artifacts acceptable. renderOrder: floor(0) default, set bells renderOrder 2, tentacles 3, snow 1, shafts 1, caustics 1... With depthWrite false and additive, order barely matters visually. Fish are opaque (depthWrite true) so they occlude properly-ish (they're emissive opaque). Fish vs jellies: fish opaque depth test vs jelly transparent — jellies drawn after, depth tested against fish depth → correct occlusion. Good.

5. Fish geometry build:

Ring triangulation non-indexed: for i in 0..rings-2, j in 0..sides-1: quad (i,j),(i+1,j),(i+1,j+1),(i,j+1) → two tris. Positions from param function. Normals: approximate analytic: for ellipse cross-section, normal in yz-plane = normalize(y/(ryry), z/(rzrz))... plus slight x-component from profile slope — easier: computeVertexNormals() after building non-indexed geometry gives faceted normals (fine for tiny glowing fish; faceted even sparkles). Actually with non-indexed, computeVertexNormals gives flat normals — fish will look low-poly faceted — with 6 sides, shimmering facets actually look good with bloom. OK use flat normals. Cap nose/tail with fans? Ends: nose ring at tn=1 has r=0 → degenerate ring = a point repeated; triangulation with zero-radius ring yields degenerate tris (zero area) — invisible but wasteful; fine, or offset: make first/last rings r=0 (points). Degenerate triangles with zero normals — could produce NaN normals (computeVertexNormals divides by zero area → normal (0,0,0)); normalized in shader normalize(0)=NaN! Avoid: clamp radius min 0.012 and in shader normal transform fine; or guard n + 1e-5. I'll clamp min radius and add epsilon in normalize: normalize(n + vec3(1e-6)).

6. Boid velocity shader hash:

Sampling neighbors: generate pseudo-random uv from (uv, i, frame):

Better standard: nuv = hash2(uv + vec2(float(i)0.61803, seed)) — ensure not equal to own uv: if distance(nuv, uv) < tiny resample via fract(nuv1.618). Add if (all(equal(nuv,uv))) nuv = fract(nuv+0.5); — comparing floats equality rare; skip, check d<1e-4 continue.

uFrame uniform: floor(simTime*3) updated per frame — changes sample set 3×/s.

7. Pulse uniforms in velocity shader: uPulseTime (float, -1 inactive), uPulsePos.

8. Lure uniforms: uLurePos (vec3), uLureActive (float 0/1).

9. In position shader: also add gentle "current" drift? Fish positions just integrate velocity. Bounds hard clamp: sphere radius 56: if length(pos) > 56: pos = normalize(pos)*56. y clamp [-27, 23].

10. Uniform typing: uJellies as array of vec4: in JS: { value: [new THREE.Vector4(), ... 8] }. THREE handles vec4 arrays from array of Vector4. uJellyVel similar array of Vector3.

Sharing these uniform objects between materials: I can share the same uniform objects across fish/bell/tentacle materials: uniforms.uJellies = { value: jelliesArray } — sharing value array reference across materials is fine.

11. Boid shader reads uJellies → must be array uniform in fragment shader of computation material — dynamic index loop constant bounds fine.

12. Fish material uses uPulsePos/uPulseTime — share uniform objects with boid material where convenient. I'll keep a shared uniforms registry object holding value objects, then reference in each material's uniforms dict: e.g. uTime: shared.uTime so updating shared.uTime.value updates all. Yes — same object reference in multiple materials' uniforms works (three just reads .value).

13. simTime frozen when paused: shared.uTime.value = simTime.

14. OrbitControls: enableDamping; autoRotate = P.autoOrbit; autoRotateSpeed. Pointer interactions with canvas coexist: drag orbits; hold... conflict: pointerdown for lure attract vs orbit drag. Resolve: attract activates on pointerdown only if not moved much? Simpler: attract while pointer HELD and not dragging (OrbitControls uses left-drag rotate). Hmm — left drag rotates; that conflicts with "hold to attract". Options: attract always ON toward lure position (fish mildly attracted), and "hold" increases pull strongly? But then orbiting triggers attraction too — acceptable? The lure follows pointer anyway, so attraction point is where pointer is; orbiting changes camera but lure stays in world. Decision: lure auto-active whenever pointer is over canvas (move = lure target), pull strength baseline ×0.4; while pointer down (any) → full pull ×1.0. Orbiting still works. It's an ambient interactive demo — fine. On touch: touch drag orbits AND sets lure → also fine.

Double-click for pulse: use 'dblclick' event + Space. Touch: two-finger tap? skip, provide GUI button "Sonar pulse".

15. GUI fish count dropdown: values {1024, 2304(48²), 4096, 9216, 16384}. Rebuild on change — dispose geometry, material, gpu targets. GPUComputationRenderer has dispose()? In r160, I don't think GPUComputationRenderer has dispose... Checking memory: r160 misc/GPUComputationRenderer.js — I believe a dispose() method was added at r15x? Not sure. To be safe: manually dispose renderTargets: gpu doesn't expose cleanup; but variables' renderTargets accessible via gpu['variables']? Property names: this.variables public. I'll write cleanup: if (gpu) { for (const v of gpu.variables) { v.renderTargets?.forEach(rt=>rt.dispose()); } } guarded with optional chaining. Plus materials dispose. If internals differ, guarded code just skips. Fine.

16. Tentacle geometry: single LineSegments with per-vertex attrs; vertices count: 8 jellies × 14 strands × (SEG-1)×2 where SEG=22 → 8×14×21×2 = 4704 verts. trivial.

Draw lines with additive blending & vertexColors? Use ShaderMaterial with attributes (aHueJ too for color). linewidth 1.

Also add small "bell core" glow: instanced small sphere inside bell with strong emissive — merge into bell shader instead: brighten upper interior via fragment term. Skip extra mesh.

17. Caustics plane: additive; alpha computed in shader; also fades with camera distance? It's at y=38, camera below — always visible looking up. With fog exp2 custom: apply fog to caustics color by depth → dims nicely.

18. Shafts: geometry PlaneGeometry(1,1) scaled per-instance? Use individual meshes (9) with random transforms stored; per-frame billboard Y rotation toward camera. One shared ShaderMaterial with per-mesh uniforms? Use onBeforeRender to set per-mesh uniform? Simpler: attributes? With separate meshes sharing material, need per-mesh seed — use mesh.position as seed inside shader via worldPos hash — fine: seed from modelMatrix[3].xz. Vertex shader can read modelMatrix.

19. Snow: one Points; attrs: position (base), aSeed(vec4: speed, swayAmp, swayFreq, size). Vertex: wrap y: float y = mod(position.y - uTime*spd, H) - H*0.5; world x,z fixed + sway. Fragment: round soft sprite; alpha *= fog. Additive, dim.

20. Rocks instanced: 30 icosahedron scaled (2-6), positioned ring radius 10-48 on floor (floor height varies — compute same CPU noise function to sit them), random rotation. flatShading standard material. Also a few big "spires" (cones)? Keep icosahedra stretched vertically sometimes. OK.

Floor CPU noise: implement small value-noise JS:

Floor height h(x,z) = sum octaves * 3.2 − base. Circle geometry rotated -90° X; displace vertices y. computeVertexNormals.

Anemone glow dots: InstancedMesh 140 tiny spheres (r 0.1-0.28) at floor positions, MeshBasicMaterial colors varied via instanceColor (setColorAt): cyan/magenta/amber. Additive? Basic material with bright color + bloom → glow. Use MeshBasicMaterial color white × instanceColor × 2 intensity? instanceColor multiplies. Set material.color (2,2,2)? color values >1 allowed via new THREE.Color(2,2,2)?? Color accepts >1 in setRGB. Use material.color.setRGB(1.6,1.6,1.6) then instance colors scale down... simpler: leave color white, pick vivid instanceColors; brightness from bloom threshold... white 1.0 luminance > 0.55 threshold → mild glow. Boost: use additive blending and color 1.5. Fine.

21. Vignette/grain shader pass:

Careful: this runs in linear pre-OutputPass; grain in linear subtle. fine.

22. Snapshot: after composer.render() in same tick — call inside function directly (renders twice that frame, fine).

23. Fonts/style consistent with other demos: dark bg, monospace HUD, cyan accent (#67e8f9).

Title: "Abyssal Bloom — a bioluminescent deep-sea ballet". Number 010. Folder /space/demos/010-abyssal-bloom/.

Index page: add card at top of list:

Note: 009 card uses <span class="num">009</span> (no "Demo" prefix) while older use "Demo 00X". I'll use "010".

Description: "A bioluminescent deep-sea ballet — 16k GPU-flocked lanternfish (GPGPU boids on float textures) swirl around procedurally pulsing jellyfish with shader-swayed tentacles, beneath voronoi caustics and fbm god-ray shafts. Steer a glowing lure with your pointer, fire a sonar pulse to scatter the school, and drift through marine snow with bloom, exp² fog, synthesized abyss ambience, live controls and PNG snapshots."

Now, let me write the actual files. I'll build in /tmp/abyss/parts and concat. Actually simpler: write the whole thing as a few write calls appending? The write tool writes whole file (or line-range). I'll write parts p1..p5 then cat them into index.html. Then extract JS & node --check.

Let me carefully compose the code now.

Demo 009 is intact. Now I'll build demo 010: "Abyssal Bloom" — a bioluminescent deep-sea scene with GPGPU boids, procedural jellyfish, fake volumetric god rays, marine snow, bloom post, synthesized ambience.

I'll write the demo in parts to /tmp/ab/, then concatenate and validate. Let me write part 1: HTML head + CSS + HUD + importmap + imports + params.

Status: 61.7% of time used, only 0.5% of iterations. Hmm, "timeProgress": 0.617 — that's concerning: over half the time budget consumed already?? I need to be efficient. But iterationProgress is tiny, so maybe time is not the binding constraint... "reasons":["maxTime"] with threshold 50 means I crossed 50% of max time. I should move fast: write remaining parts in fewer, larger writes, concatenate, validate, deploy, update index, finish.

Let me write part 2 now (renderer/scene/camera/post + environment). Make it complete and careful.

*******************************************************************************************************************************************************************************************************************************************************02.

********************************************************************************************************ly.

Note: GLSL_FOG is defined in p02 before p03 — good, it's in scope (module top-level, defined earlier). gpu.variables — in GPUComputationRenderer, the property is this.variables? Let me double check: in r160 source, GPUComputationRenderer has this.variables = [] — yes, public. And v.renderTargets is an array of 2. Good, guarded with try/catch anyway.

One concern in POS_FRAG: I reference uBounds from BOID_FRAG_COMMON — included. But POS_FRAG doesn't use most uniforms — unused uniforms are fine.

In the velocity shader, normalize(pos.xz + vec2(1e-4)) — normalize of vec2, fine.

uniform vec4 uJellies[${MAXJ}] — MAXJ is 8, template literal injects "8" — good. Loop for(int j = 0; j < 8; j++){ if(j >= uJellyCount) break; ...} — uJellyCount is int uniform — comparison int vs int fine.

Fish shader: varying vec3 vW used in fragment for pulse distance — good. uTime unused in FISH_FRAG? I use it? No — I declared uniform float uTime, uPulseTime; but only use uPulseTime. Unused uniform fine (may warn, ok). Actually keep — no issue.

fishMat uniforms include uTime: shared.uTime — used in vertex shader. Good.

One issue: geo.instanceCount = N; — InstancedBufferGeometry instanceCount; fine.

In buildFishGeometry, ringPt at tn=0 → prof = sin(0)=0 → r=max(0.012, 0)=0.012 — tail ring small circle; at tn=1 → pow(1,0.78)=1, sin(π)≈1.22e-16 → 0 → 0.012 blunt nose. Good, no degenerate zero-area.

computeVertexNormals on non-indexed → flat normals. normals of tail fin: both triangles in XY plane → normal ±Z. Fine with DoubleSide.

Wag: p.z += wag * (...) * (0.35 - 0.45*aBody) * sc; — at head aBody=1 → factor -0.1 (slight counter-sway, natural), at tail aBody=-1 → 0.8, tail fin aBody=-1.6 → 1.07. Good.

right = normalize(cross(up, fwd) + eps) — if fwd parallel up, cross ≈ 0 + eps (1e-5,0,0) → normalize fine.

Now part 4: jellyfish (bells + tentacles), jelly CPU sim, lure visuals, sonar pulse ring.

82% of time used. I must move very fast now. Write part 5 (audio, input, GUI, loop, init, closing tags) in one big write, then concatenate, node --check, deploy to /space, update index, done. Skip further checkpoints.

Let me write part 5 carefully and completely.