Decouple viseme timing from 32ms audio chunks by introducing an independent
FVisemeTimelineEntry timeline evaluated at render framerate. Playback-time
envelope tracking from consumed queue frames replaces arrival-time-only
updates, with fast 40ms decay when queue is empty.
- Viseme subsampling caps at ~10/sec (100ms min) to prevent saccades
- Full-duration quintic smootherstep crossfade (C2 continuous, no hold phase)
- Dead zone lowered to 0.15 for cleaner silence transitions
- TotalActiveFramesSeen cumulative counter for accurate timeline scaling
- Absolute cursor preservation on timeline rebuild
- Moderate Lerp smoothing (attack 0.55, release 0.40)
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
j.foucher
e57be0a1d9