Particle and physics scenes need hard bounds, explicit ownership, and runtime inspection because small parameter mistakes can produce large visual failures.

Particle planning

• Define spawn rate, count, lifetime, velocity, color, size, depth, and decay before adding pointer or scroll interaction.
• Keep force fields and vector fields named by purpose: focus, drift, orbit, avoidance, collision, or burst.
• Set density for the weakest expected device rather than the authoring machine.

Physics planning

• A physics world should own bodies, joints, forces, collisions, coordinate scale, pause behavior, and body writers.
• Avoid double-writing a physics body transform. Physics should own the pose or the graph should own the pose, not both.
• Scope body selectors through a frame or stable data attributes to avoid future phantom bodies.

Debug and validation

• Use debug.physicsWorld(), physicsBody(id), physicsBodyIds(), physicsCollisionLog(), physicsBodyAt(x, y), physicsBodyGeometry(id), and physicsJoints().
• Relevant codes include PHYSICS_NO_WORLD, PHYSICS_MULTIPLE_WORLDS, PHYSICS_BODY_REF_MISSING, PHYSICS_PPM_INVALID, PHYSICS_BOUND_DOUBLE_WRITER, and stagger/frame warnings.

Verified runnable example

This guide points to proof-backed sample coverage. The full ledger lives in Generated examples and proof log.

Canvas: Fill rule diagnostic

• Source: faster-motion/demo/tests/canvas/fillrule-diagnostic/fillrule-diagnostic.fmtion
• Expected output: A contained Canvas scene renders paired path cases so nonzero and evenodd fill handling can be compared visually.
• Validation: Schema validation passed. Runtime proof reports zero blocking runtime issues and 10 rendered objects; the accepted metadata note is preserved in the proof ledger.
• Desktop proof: generated-assets/faster-motion-docs/proofs/screenshots/canvas-fillrule-diagnostic-desktop.png
• Mobile proof: generated-assets/faster-motion-docs/proofs/screenshots/canvas-fillrule-diagnostic-mobile.png

Guide-specific sample target: Particle and physics sample with one bounded emitter, one physics world, one body pick, collision log, and frame screenshots.

Faster Motion docs

Use this local map together with the left navigation. The source-backed content tree controls the main article order; this section keeps related pages one click away.

Start

• Faster Motion docs map
• Faster Motion documentation overview
• Get started with Faster Motion
• Faster Motion concepts
• .fmtion file format

DOM animation

• DOM animation guide
• DOM selectors and targets
• Scroll animation
• Pointer, hover, and drag inputs
• Text, SVG, and path animation
• Responsive gates and parameter overrides

Canvas animation

• Canvas animation guide
• Canvas area lifecycle
• Canvas objects, assets, and rendering
• Canvas inputs and state machines

3D and procedural

• Canvas 3D and procedural guide
• 3D scenes, cameras, and lights
• Procedural geometry and fields
• Particles and physics

Reference

• Node reference index
• Node categories reference
• Runtime loading and publishing
• Runtime API reference
• Debugging and preflight
• Debug API reference
• Validation errors and warning codes
• Faster Motion production checklist
• Faster Motion recipes overview