API

Import Prism from the package root:

import { CanvasRuntime } from "@synthesisengineering/prism";

Everything outside the package root is not public API. Runtime internals, backend classes, and raw HTML-in-Canvas wrappers are internal.

Public exports

CanvasRuntime is the only constructible public runtime class.

CanvasSurface is a public TypeScript type. Surface instances are returned by registerSurface() and should not be constructed by apps.

onPaint() and onUpdate() are additive. They register another handler and do not replace existing handlers.
invalidate() schedules another Prism-owned paint pass; it does not store app state.
Registering the same element with the same runtime returns the existing CanvasSurface; new options are not reapplied.
paintOnce() works without start(). Pending paintOnce() waiters reject if a paint handler throws or the runtime is destroyed.
destroy() disposes registered surfaces. Disposed surfaces report isDisposed === true; getBounds() and setBounds() throw.
Prism does not expose a general event system or unsubscribe API today.