fix(element): withhold paint until a pixel translate actually settles - #122
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DouweBos wants to merge 1 commit into
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fix(element): withhold paint until a pixel translate actually settles#122DouweBos wants to merge 1 commit into
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The withheld-paint reveal was bounded to one extra layout pass, so a translate that folds into the position later still painted the node at its untransformed origin for a frame. Wait for isTranslateSettled, bounded by a pass count so an undetectable translate can't strand the node invisible.
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What
LightningViewElementwithholds paint until a node's first layout resolves, andisTranslateSettledextends that so a pixel translate isn't revealed at its pre-transform origin. The reveal was bounded to exactly one extra layout pass:hadLayout ||short-circuits the check, so the second layout reveals unconditionally. A translate that folds into the position later than that — deeper in the async flex tree — still paints the node at its base position for a frame.The reveal now waits for
isTranslateSettledto actually return true, bounded byMAX_UNSETTLED_LAYOUTSso a translate the heuristic can't detect (percentage translates, right/bottom anchoring) still can't strand the node invisible.Why
Found while tracking down a drawer in the Plex RN client that is laid out on screen and translated off: at mount it flashed open for a frame before the translate landed.
Tests
Two cases added to
LightningViewElement.spec.ts. Both fail onmainfor the right reason — the node reveals on the second layout pass while still unsettled:Full package suite green (307 tests),
tsc --noEmitandoxlintclean.Note on formatting
Left the touched files as-committed rather than running
oxfmt— the repo's committed formatting predates oxfmt 0.45, so--checkalready fails on 5 files insrc/element/onmain. Running it here would have added ~190 lines of unrelated churn. Worth a separate formatting pass.