Particle Galaxy Skill

Produce a single self-contained index.html that renders a real-time particle system full-screen, with a clean typographic overlay on top. The signature move: compute each particle's position on the GPU so the CPU never loops over particles.

Why this is a powered artifact

OpenDesign detects getContext('webgl2') and renders this file in powered preview — a cross-origin-isolated iframe with allow-same-origin. The full GPU pipeline is available; you do not need to work around the opaque sandbox.

Resource map

webgl-particle-galaxy/
├── SKILL.md      ← you're reading this
└── example.html  ← a working 50,000-point WebGL2 galaxy (READ FIRST)

Workflow

Step 0 — Read the reference

Read example.html end to end. Note the shape: no vertex buffer — the vertex shader reads gl_VertexID, hashes it into a stable per-particle seed, and derives a log-spiral orbit with an inner-fast rotation curve. Points are drawn with gl.drawArrays(gl.POINTS, 0, N) in one call, additive-blended (blendFunc(ONE, ONE) with premultiplied color) so overlapping points glow.

Step 1 — Pick the motion

Choose a field the vertex shader can expres…