* fix(render): make WebGL video textures deterministic in headless render
WebGL compositions that sample a `<video>` as a texture (e.g. a faceted
crystal with clips mapped onto its facets) rendered with flickering,
non-deterministic facets: a video would intermittently show a stale frame or
go black, and the same frame differed between two renders.
Two gaps caused this:
1. No WebGL analog of the WebGPU `patchVideoTextureCompat`. Chrome's headless
compositor can't feed decoded `<video>` frames to the GPU, so the engine
injects a decoded `<img class="__render_frame__">` sibling per video each
frame. The WebGPU `copyExternalImageToTexture` path substitutes it, but
`texImage2D` / `texSubImage2D` did not — so WebGL uploaded a stale/black
frame. Add `patchWebGLVideoTextureCompat()` mirroring the WebGPU patch
(shared `resolveRenderFrameImage` helper).
2. Capture ordering. Per frame the runtime seeks (GPU adapters render on
`hf-seek`) BEFORE the engine injects the decoded frames, so the GPU render
read a frame that didn't exist yet. After injecting, the engine now calls
`window.__hfReseekGpu(t)` — a force-dispatch (`forceDispatchSeekEvent`) that
bypasses the same-time `hf-seek` dedup — so GPU compositions re-upload their
textures from the freshly-injected, decoded frames, deterministically.
Tests: unit tests for the texImage2D/texSubImage2D substitution and the
force-dispatch, plus a videoFrameInjector regression test asserting the
post-injection GPU reseek fires only when frames were injected. Verified
end-to-end: a WebGL prism with 8 live <video> facets renders byte-identical
across independent runs with no facet flicker.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
* test(render): add producer render-compat regression for WebGL video textures
A WebGL2 canvas samples a <video> as a texture every hf-seek (the natural
author pattern, distilled from the HeyGen prism). The render-compat harness
renders it and compares against the golden: with the video-texture fix the
render reproduces the decoded frames; revert the fix and the canvas renders
black, collapsing the comparison.
Golden verified to contain real, time-varying video content (not black), so a
regression is caught rather than passing vacuously.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
---------
Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Two follow-ups to the ancestor-visibility skip in `injectVideoFramesBatch`
and `syncVideoFrameVisibility`.
1. **Mask defence.** Both ancestor-hidden branches previously wrote a plain
`img.style.visibility = "hidden"`. `applyDomLayerMask` writes the
stylesheet rule `#${showId} *{visibility:visible !important}`, and CSS
cascade puts important stylesheet author above non-important inline
author — so a sub-comp host landing in the active layer's `show` set
would revive a stale `__render_frame__` and let it bleed onto the
layer composite. Write the hide via
`style.setProperty("visibility", "hidden", "important")` instead;
important inline beats important stylesheet.
2. **Caller cache hygiene.** `createVideoFrameInjector` unconditionally
wrote `lastInjectedFrameByVideo.set(id, frameIndex)` after calling
`injectVideoFramesBatch`, even for videos the page silently skipped due
to a hidden visual ancestor. On the next call at the same frameIndex —
common with source-fps < output-fps, paused source frames, or
non-frame-aligned host starts — the cache short-circuited the second
inject and the host's first visible frame painted blank because the
replacement `<img>` was never created.
Make `injectVideoFramesBatch` return `string[]` (the subset of ids it
actually painted) and have the caller cache only those. The cli-side
`snapshot.ts` consumer is unaffected: its local `InjectFn` types the
return as `Promise<void>`, which is structurally compatible with
`Promise<string[]>` under TS void-return assignment rules.
Tests: linkedom doesn't preserve `!important` in cssText, so the two new
mask-defence cases spy on the live `<img>`'s `style.setProperty` and assert
the 3-arg call shape. The cache-hygiene case stubs the page-side primitives
via `vi.mock`, drives the hook twice at the same frameIndex with a stubbed
"injected nothing" first response, and verifies the second call still
issues an inject. A counter-test pins the happy-path cache hit so a future
refactor can't trade the skip bug for a never-cache regression.
ukimsanov