VideoComposeSettings.structuralUpdateMode property

How a STRUCTURAL composition update — a layer added or removed, or a part’s sourceRect appearing/disappearing — is applied on the Spectrum arms, which rebuild their compiled pipeline for such changes. Non-structural updates (geometry, opacity, transitions) always apply in place regardless of this setting. Silently ignored by the other backends.

  • "glitch-free" (the default): make-before-break — the previous composition keeps rendering while the new pipeline is prepared, then output cuts over. Output never pauses and no frames are dropped, but the change lands a few frames late (or seconds late the first time a never-before-seen structure is compiled on a box; compiled pipelines are cached in memory and on disk, so that’s a first-time-only cost). - "frame-accurate": break-before-make — output pauses at the update point, input frames queue, and every queued frame is rendered with the new composition once the pipeline is ready. Choose when the exact frame the update applies at matters more than continuous output.

Signature:

structuralUpdateMode?: "glitch-free" | "frame-accurate";