Worker, Canvas and Wasm

Use examples/stardust for decoration and examples/worker-canvas for computation and drawing. Separate one-shot user computation from continuous animation: hiding may stop drawing without cancelling useful calculation.

Worker ownership and backpressure

Workers have no direct host bridge. The main page calls widgetHost, validates bounded input and sends business data to package-local Worker code. Bundle Wasm and scripts locally. Include task IDs and reject stale results.

Allow one in-flight computation. Continuous drawing may keep one in-flight message and one newest pending value, sending again only after consumption acknowledgement. Limit input/output size, deadlines and frequency. Terminate on error/timeout and wait for explicit retry, without infinite restart loops.

Lifecycle and fallback

Detect capabilities and actually verify initialization. API existence is not successful execution. Offer Canvas2D, a static frame or an unavailable explanation if OffscreenCanvas/WebGL2/Wasm initialization fails.

Draw one reduced-motion frame, lower energy-saver frequency and pause hidden/locked/suspended drawing. Resume with current state rather than accumulated frames. On pagehide terminate Workers, cancel frames/timers and remove listeners.

Wasm compilation may finish late; cancellation guards later instantiation/DOM updates and does not claim to stop engine compilation. Initialize audio after appropriate user interaction, respect host audio/lifecycle and release nodes/AudioContext when leaving.

Verify backpressure, cancellation, timeout, initialization failures and static fallback. See stardust, development and audio.