fix(slideshow): make slide holds deterministic (no auto-progress)#1596
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vanceingalls wants to merge 2 commits into
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fix(slideshow): make slide holds deterministic (no auto-progress)#1596vanceingalls wants to merge 2 commits into
vanceingalls wants to merge 2 commits into
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playTo() played the player and relied on being paused at holdAt = target + 0.2s (~6 frames). If a timeupdate was coarse or missed, playback overran the hold — sometimes into the next fragment/scene, the intermittent auto-progress. Bound the repaint to a single frame instead: seek to the exact target, play, and pause on the FIRST timeupdate at/after the target. timeupdate only fires from the playback clock (never on seek), so the first tick is a genuine painted frame — one tick forces a repaint but can't overrun. Pause before the change handlers so no second tick advances the playhead. Verified headless: slide holds with currentTime stable over 6s; every next lands and holds (1→2 frag0→2 frag1→3), no drift. 106 player tests pass.
Supersedes the single-frame play-nudge: that left a backgrounded audience window playing (waiting for a throttled timeupdate to pause it) → drift and the 'one side doesn't move' desync. - SlideshowController: navigation is now a pure synchronous seek (no sustained playback, no auto-progress). fragmentIndex is advanced by the caller, not on a played tick. Removed holdAt/holdTarget/onTime and the timeupdate subscription. - Player: _tryDirectTimelineSeek now seeks with suppressEvents=false so the composition's root-timeline onUpdate fires — imperative scene-visibility decks (slideshows) repaint on a paused seek, not only while playing. (Direct-timeline seek is the bare-player/present path; the runtime path already repaints.) Verified two-window headful: presenter + audience both land on the same scene, paused, no drift; audience visibly shows the correct slide. 268 player tests pass.
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Follow-up to #1585 / #1594 (both merged). Fixes the intermittent auto-progress flakiness in slideshow presenter mode.
Root cause
playTo()played the player and relied on being paused atholdAt = target + 0.2s(~6 frames at 30fps). If atimeupdatewas coarse or missed, playback overran that window — sometimes into the next fragment or scene. That's the flaky auto-progress.Fix
Bound the repaint to a single frame: seek to the exact target, play, and pause on the first
timeupdateat/after the target.timeupdatefires only from the playback clock (never onseek), so the first tick is guaranteed to be a genuine painted frame — one tick forces the repaint a bare paused seek can't produce…Verification (headless)
currentTimestable over 6s (paused, no drift).nextlands and holds: 1/11 → 2/11 (frag0 @9.3) → 2/11 (frag1 @9.6) → 3/11 @22.5 — each still stable after a 2.5s wait.One file (
SlideshowController.ts); removes the now-unusedRENDER_NUDGEconstant.🤖 Generated with Claude Code