Georg/ai.interactive.fiction
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Reuse spanning-aware prepared plan at activate (kill pre-playback pause)

Browse Source 
A spanning block stalled ~2.1s before it began playing: activate ran prepareRevealBlock
with forceRebuild, synchronously redrawing the start spread (and preloading the
continuation spread) on the main thread, because the lookahead plan had been built with
right-only timing before pagination committed the overflow.

Build the start-spread plan spanning-aware during lookahead instead: when the preview
layout shows the block overflows, derive its timing across both preview spreads (via the
revealSpreadSourceOverride) and cache it. activate then reuses that plan — the same fast
cached-plan path non-spanning blocks already use — with no synchronous redraw. forceRebuild
is kept only as a fallback when a block spans but was not prepared spanning-aware (e.g. an
immediate prepare with no preview layout), and an evicted plan still rebuilds correctly
because pagination is committed by then.

Verified live: the spanning block's pre-playback gap dropped from ~2088ms to 139ms (equal
to non-spanning blocks), while the right line still reveals over its area share (~3.3s),
the continuation still animates from the start, and there are no fast-forwards or problems.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
This commit is contained in:
Georg Tomitsch
2026-06-19 00:10:25 +02:00
parent 47af10d60c
commit 28d5e51c92
3 changed files with 61 additions and 34 deletions
Download Patch File Download Diff File Expand all files Collapse all files
public/js/book-texture-renderer-module.js
+19 -6
View File
@@ -916,17 +916,30 @@ class BookTextureRendererModule extends BaseModule {
this.revealPublishBlockIds = new Set([id]);
const spread = detail.spread || this.currentSpread || this.pagination?.getCurrentSpread?.();
const sides = ['left', 'right'];
const published = this.drawSpread(spread, sides, {
phase,
publishEvent: options.publishEvent !== false
});
this.preloadAdditionalRevealSpreads(id, spread);
// When the caller supplies the (not-yet-committed) preview spreads for a spanning
// block, derive this spread's reveal timing across all of them so the cached plan
// already spans both pages. activate can then reuse it instead of forcing a
// synchronous rebuild on the critical path.
const spanningPreview = Array.isArray(detail.previewSpreads) && detail.previewSpreads.length > 1;
const previousOverride = this.revealSpreadSourceOverride;
if (spanningPreview) this.revealSpreadSourceOverride = detail.previewSpreads;
let published = null;
try {
published = this.drawSpread(spread, sides, {
phase,
publishEvent: options.publishEvent !== false
});
} finally {
this.revealSpreadSourceOverride = previousOverride;
}
if (!spanningPreview) this.preloadAdditionalRevealSpreads(id, spread);
if (phase === 'prepare' && published) {
this.pageCache?.rememberPreparedRevealPlan?.(id, {
...published,
blockId,
wordTimings,
totalDuration: detail.totalDuration || 0
totalDuration: detail.totalDuration || 0,
spanningTimingPrepared: spanningPreview === true
});
}
this.markPipelineTiming('prepareRevealBlock:end', {