[obiot]

Description

A camera draws a renderable only if it and every container above it share a layer with the camera's cullMask. Particles stayed on layer 1 whatever their emitter was on. So the way to give an effect a camera of its own, putting the emitter on a layer and giving that camera a cullMask of just that layer, drew the emitter and none of its particles. (Leaving an emitter out of a camera already worked, because the container check covers its children.)

emitter.visibilityLayer = SPACE;   // 2
spaceCamera.cullMask = SPACE;      // before: no particles drawn

The fix follows the emitter's existing blendMode pattern:

• a particle is born on its emitter's visibilityLayer (in Particle#onResetEvent, so a pooled particle no longer keeps the layer of its last life);
• the emitter fans a change out to the particles already alive on its next update. This costs one number compare per emitter per frame.

A getter on Particle reading the parent's layer would have been simpler, but TypeScript rejects an accessor overriding Renderable's plain property (TS2611).

Also:

• Changelog: a Fixed entry.
• TSDoc: a "Visibility layers" section on ParticleEmitter.
• Skills: the camera skill's visibilityLayer / cullMask section and a symptom row in the particles skill.

Found while building the Starsweep example, whose 3D star-dust background is drawn by a second, Camera3d, camera on its own layer.

Type of change

• Bug fix
• New feature
• Documentation update
• Performance improvement
• Refactoring (no functional changes)

Checklist

• I have read the Contributing Guide
• My code follows the existing code style (pnpm lint passes): Biome clean, tsc clean, no new ESLint warnings
• I have tested my changes locally (pnpm test passes): camera-cull-mask and every particle-* spec pass (207 tests)
• I have added tests that cover my changes (if applicable): three in tests/camera-cull-mask.spec.js; the two behaviour tests fail without the fix
• The build succeeds (pnpm build): left to CI

Related issues

None.

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Generated by Claude Code

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