* fix(engine): motion blur works over video by holding each video frame across samples
Each output frame's injected video frame is now held for every sub-frame
sample and probe of that frame, so footage stays as shot and only the
layers over it blur. The refusal for sessions with a before-capture hook
is removed.
Fixes#5144
* fix(engine): trim held-video comments, pin the new test-classification hash
* fix(engine): a blurred frame at a sub-composition cut keeps its video
Each sample now decides which videos show at its own time, like every other
layer, and only a video on screen at the output frame's time keeps that
frame's picture. Before, the visible set was taken at the frame's time while
sub-composition hosts were hidden at the sample's time, so the samples just
before a cut showed no video and the cut frame dipped toward black. The
before-capture hook takes the held time as an optional third argument, and
the early injection is gone: the GPU re-render now always runs at the page's
own time.
* style(engine): one doc comment for the before-capture hook
* fix(engine): a video animating its own style stays in step when blurred
The injector copies a video's own style only when its frame changes, so the
first injection of each blurred frame now runs at the frame's own time
before the samples. A video sliding by its own transform no longer sits a
quarter frame behind with blur on.
* test(producer): a two-line header for the motion blur over video test
* test(producer): reach the cut fixture by path, not a URL fallow reads as an import
Miguel Ángel
3b89bfe8a7