* feat(studio): mirror canvas z-order actions into timeline lanes, badge z overrides
Track order = default paint order; authored z = advanced override.
- timelineZMirror.ts: pure resolver mapping a successful z-menu action to a
timeline lane move — closest track in the action's direction that is free
over the clip's whole span, else a new lane adjacent to the crossed
neighbor; temporal-overlap scope (default pending product sign-off, see
module doc); visual zone only; same-file reference scoping; persistTrack
via the shared authored-space rules. null for non-clips (menu stays
z-only) and at-extreme/no-overlap cases.
- useCanvasZOrderTimelineMirror.ts: after the z commit resolves, the mirror
persists the lane move through the same machinery as a timeline lane drag
(optimistic store update, authoredTrack refresh, rollback); inserts reuse
commitTrackInsert's renumber via a shared buildTrackInsertEdits core. Both
writes share one coalesce key (zReorderCoalesceKey) and fold into ONE undo
entry (test proves it over the real history reducer). The mirror never
triggers the lane->z stacking sync, so it cannot fight the z values the
action just set.
- timelineZOverride.ts + TimelineClip badge: clips whose paint order
contradicts lane order among temporally-overlapping same-context visual
neighbors (laneIsAbove XOR paintsAbove, the stacking-sync predicates) show
a 'z' badge — authored z overrides are surfaced instead of silently
disagreeing with the timeline.
- Timeline.tsx track derivations extracted to useTimelineTrackDerivations
(600-line cap).
* fix(studio): fold mirrored z-order gestures into one undo entry across slow persists
Live verification caught the z write and the mirrored lane write splitting
into two undo entries: the mirror runs after the z persist's server round
trip, which exceeds editHistory's default 300ms coalesce window under real
latency (the unit test's deterministic clock sat inside it).
zReorderCoalesceKey now mints a per-gesture-unique key (monotonic seq, the
laneChangeGestureSeq precedent) and both records carry coalesceMs Infinity —
distinct gestures can never merge, and one gesture always folds regardless
of write latency. coalesceMs threaded through the persist chain alongside
coalesceKey. Also hardens the existing lane-drag move->z fold, which had the
same latent split. Fold test now simulates a 400ms gap (failed before the
fix, passes after); a two-separate-gestures test asserts two entries.
* feat(studio): flashless lane mirror, z-order menu icons, close-gap track menu
- Track-only batch moves (the z-mirror's lane hop and the insert renumber)
skip the GSAP fallback round-trip and the preview reload entirely — the
renderer never reads data-track-index, and the live DOM patch + optimistic
store update cover the UI. Mixed batches keep current behavior. Kills the
canvas blink on mirrored Bring/Send actions (live-verified: an
iframe-scoped marker survives the whole gesture).
- The four z-order menu items get 16px stroke icons (single layer diamond +
directional arrow for Forward/Backward; pierced two-layer stack for
Front/Back); labels unchanged — they are the industry-standard names.
- New track context menu on empty lane space: 'Close gap' (shifts the next
clip and every clip after it on that lane left by the clicked gap's width;
leading gaps count, so a single clip with empty space before it compacts
to 0) and 'Close all gaps' (whole lane contiguous from 0). Pure gap math
in timelineGaps.ts; persists through the drag path's atomic batch move
(one undo per action); refuses when a clip that must shift is locked;
items disable when there is nothing to close.
* fix(studio): rebind-only preview sync for unmutated timing edits, classical z-menu order
Timing edits that rewrote NO GSAP positions (gap closes and moves of
selector-addressed caption clips, zero-delta batches, comps without a
rewritable script) full-reloaded the preview — and the rerun-current-scripts
attempt was wrong for real compositions: re-executing init-style scripts
(three.js scenes, caption engines) is exactly the unsafe case, verified live
by doubled init warnings and a fallback reload anyway.
The correct observation: when mutated === false the existing __timelines are
still valid — only the runtime's clip visibility windows are stale, and the
live DOM timing attributes were already patched. So the no-mutation path now
runs applySoftReloadFinalization only (seek + __hfForceTimelineRebind +
manual-edits reapply), extracted from the soft-reload machinery — zero
script execution. This also un-blinks comps with no GSAP script at all,
which previously always remounted. Rewritten-script soft reloads,
cannot-soft-reload, otherFileChanged, and mutation failures keep their
existing behavior. gsapSoftReload's undo/redo restore section moved verbatim
to gsapUndoRestore.ts for the 600-line cap.
Also: z-order menu items reordered to the classical arrangement (Bring to
Front, Bring Forward, Send Backward, Send to Back).
Live-verified on a three.js-heavy composition: Close-all-gaps shifted 4
caption clips with correct cumulative amounts, the preview iframe was never
remounted (marker survived), and one undo reverted everything.
* fix(studio): bound forward/backward mirror to a one-element step
User-specified semantic: Bring Forward / Send Backward move the clip past
EXACTLY ONE element. The mirror's lane target is now bounded by the next
temporally-overlapping element beyond the crossed neighbor: a free lane
strictly between the two is taken (closest to the neighbor), and when they
are back-to-back a new track is inserted immediately beyond the crossed
element — never past the second one. Previously the resolver took the
closest free lane anywhere beyond the neighbor, which could carry the track
past a second element while the z action only stepped past one — a
track/paint contradiction our own zOverride badge would flag. Front/back
keep whole-set semantics (past everything; back stays above the audio
zone). End-to-end test pins the 3-stacked case through commitZMirrorLaneMove
to the persisted renumbered tracks.
* feat(studio): permanent gap-menu rows with hover and click-select gap highlights
- TrackGapContextMenu always renders both rows; an inapplicable action dims
with a tooltip ("No gap here" / lock reason / "No gaps on this track")
instead of vanishing into a one-item menu. Width badge only when a gap
exists under the pointer.
- Hovering an ACTIONABLE row highlights the strip(s) it would close in the
timeline: the single gap for Close gap, every current gap (leading included)
for Close all gaps. New resolveAllGapIntervals in timelineGaps.ts reports
present-state intervals (epsilon-tolerant, overlap-safe), distinct from
resolveAllTrackGaps' post-compaction starts.
- Click-selecting a single clip paints a quieter tint over its lane's gaps
(suppressed for marquee multi-selection and during drags; the gap-menu hover
wins on its own lane). Derivation lives in useTimelineGapHighlights with the
pure buildTimelineGapStrips exported and unit-tested.
- Strips render in TimelineCanvas with the drop-placeholder geometry (row top
+ clip inset), dashed accent for hover, faint tint for selection.
- Timeline.tsx stayed under the 600-line cap by extracting the scroll-viewport
plumbing (ResizeObserver width + shortcut-hint sync) into
useTimelineScrollViewport, behavior unchanged.
* feat(studio): stronger capcut-style timeline zoom steps
One button press / pinch gesture now moves the zoom meaningfully: step
factors 1.25x/0.8x -> 1.5x/(2/3) (kept reciprocal so in+out round-trips) and
pinch sensitivity 0.0035 -> 0.007. Addresses "zooming several times to get
anywhere" feedback; cursor anchoring unchanged.
* feat(studio): three-way z sync — layers drags mirror timeline lanes, panel tracks live z edits
Completes the layers/canvas/timeline sync triangle: the Layers panel was the
one surface whose reorders never reached the timeline, and the one that went
stale when the other two wrote z flashlessly.
- Layers drag -> minimal z + equal-jump lane mirror. handleReorder now uses
the canvas menu's realization core via resolveZOrderReposition (one
between-z write when a strict gap exists, band-safe scoped renumber
otherwise) instead of computeReorderZValues' all-sibling stamp — that
helper is deleted, completing the #2347 unification follow-up. The drop
then mirrors into a timeline lane move through the same machinery as the
canvas menu (new resolveRepositionLaneMove: the clip lands on a free lane
strictly between its NEW paint neighbors' lanes — nearest clip siblings in
the desired render order, decorations skipped — else a track insert at
that boundary; audio zone never crossed). Both writes share one
per-gesture zReorderCoalesceKey with an unbounded fold window, so a drag
is exactly ONE undo entry; useCanvasZOrderTimelineMirror's plumbing is
factored into useMirrorLaneMoveCommit and reused by the new
useLayerReorderTimelineMirror. A same-slot drop is a hard no-op (new
order-equality guard in resolveZOrderReposition).
- Panel staleness fix: flashless z commits (skipReload) reload nothing and
bump no refreshKey, so the panel's z-sorted order went stale while paused.
handleDomZIndexReorderCommit now bumps a store zEditVersion on apply AND
rollback; the panel re-collects on it. Verified live: the panel re-sorts
the instant a drag commits and again on undo.
- Layer click reveal (useLayerRevealOverride): clicking a layer that stays
hidden at the current frame (animation-parked opacity, non-clip
display/visibility hides, hidden ancestors) temporarily forces the chain
visible with live inline styles — exact priors restored on deselect, on
another reveal, on play, and on unmount; never persisted (file diff == 0
verified live). Clips keep the existing seek-into-window behavior; the
override applies on a short defer so a seek-revealed clip needs none.
- layerOrdering's unused hasExplicitZIndex probe (zero callers) removed.
Live-verified on a bed copy: a 2-position layers drag wrote exactly one
element (z 6->23 + data-track-index 15->2), the timeline lane moved without
a reload, and a single Cmd+Z restored the file byte-identically.
* feat(studio): full-track selection highlight, borderless gap hover strips
- Click-selecting a clip now lights the WHOLE lane minus its clips — leading
gap, inter-clip gaps, and the open space after the last clip to the rendered
end (new resolveLaneEmptyIntervals; displayDuration threaded into the strip
derivation). Still click-only: any drag/resize suppresses the strips, and a
marquee multi-select never shows them.
- The gap-menu hover strips drop the dashed border (user feedback) — fill only,
nudged to 0.18 alpha to keep the same visual weight.
* feat(studio): selected layer paints on top via a reader-transparent z lift
Clicking a layer in the Layers tab now shows the element as if it were at the
very top of the stack while selected — whatever its authored z or panel
position — extending the reveal override (which already forced hidden chains
visible) with a temporary inline z lift:
- liftElementToTop parks the TRUE effective z in data-hf-reveal-prior-z and
writes a far-top inline z; a static element gets a layout-preserving
position:relative with its prior parked in data-hf-reveal-prior-pos. Only
the RENDERER sees the lift: all three studio z readers
(readTimelineElementZIndex, getElementZIndex, readEffectiveZIndex) return
the parked prior while the attribute is present, so the canvas z-menu, the
zOverride badge, the lane mirror, the stacking sync, and the panel sort
keep reasoning on the element's real z.
- Strictly ephemeral: exact priors restored on deselect / another reveal /
play / unmount, each property only while it still holds the value the
override wrote (a later real edit is never clobbered). File diff == 0
verified live across a full lift/restore cycle.
- A z-reorder commit CONSUMES an active lift (handleDomZIndexReorderCommit
reads the parked position for its persist-position:relative static check,
then drops the attributes) — the committed z becomes the truth and the
later restore is a guarded no-op.
* fix(studio): flashless undo/redo — three full-reload causes in the soft-restore path
Cmd+Z blinked the canvas on essentially every undo. Three independent causes
in applyUndoRestoreToPreview, each sufficient on its own:
1. Master-view path gate: activeCompPath is NULL at the master view, so the
'paths[0] === activeCompPath' eligibility check could never match the
index.html restore and every default-view undo full-reloaded at the first
gate. Normalized to the codebase-wide 'activeCompPath ?? "index.html"'.
2. Nested identity innerHTML check: the diff compared each identified
element's innerHTML, but the composition root wraps every clip — any child
change re-detected at the root rejected the restore. Change detection now
compares only each element's OWN attribute surface; structure/text
integrity is still guaranteed by the normalize-residual whole-doc pass
(text nodes, added/removed elements, and un-identified attrs all remain
after normalization and force the full reload).
3. id-only identity: elements addressed by data-hf-id / selector (no DOM id)
fell outside the diff entirely. Identity is now id OR data-hf-id, with the
live sync resolving either.
Also stop re-running an UNCHANGED GSAP script: attribute-only restores (z,
lane, timing, style — the overwhelmingly common undo) now use the rebind-only
finalization (seek + __hfForceTimelineRebind + manual reapply, zero script
execution — the same path as flashless timing edits), instead of tearing down
and rebuilding live timelines or full-reloading when the script can't be
scoped. A restore whose script text genuinely changed still re-runs it via
applySoftReload, and structural restores (split/delete) still full-reload.
Live-verified on the bed (iframe marker): gap-close undo AND redo both keep
the iframe mounted, live DOM lands on the restored values, disk restored
byte-identically.
* feat(studio): left breathing pad before t=0, double zoom sensitivity again
TRACKS_LEFT_PAD (48px) — the horizontal sibling of TRACKS_TOP_PAD: empty lane
surface between the sticky gutter and the ruler's 00:00 / the first clips,
scrolling WITH the content.
- The lanes and the ruler realize it as a plain flow spacer between the
sticky gutter cell and the time-mapped content div, so every
content-relative computation (clip left = t*pps, beat lines, lane-menu
time, clip drag deltas) is untouched by construction.
- Canvas-space overlays shift by the pad: playhead (getTimelinePlayheadLeft),
gap strips, drop placeholder, snap guide, range highlight, marquee clip
rects, beat SVG; the insert line spans the pad.
- Every pointer->time inverse subtracts it symmetrically: seekFromX, razor,
range/marquee anchors, asset drops, and the zoom-anchor gutter basis; fit
pps and the display width account for the consumed viewport width.
- Live-verified: t=0 clip edge, the 00:00 tick, and the playhead line center
all sit at GUTTER + TRACKS_LEFT_PAD, and a ruler click lands the playhead
center exactly under the pointer.
Also doubles the timeline zoom sensitivity again (user feedback after
feel-testing the first bump): button steps 1.5x/(2/3) -> 2x/0.5, pinch
0.007 -> 0.014.
* fix(studio): left pad renders as true empty space, not lane surface
The pad before t=0 inherited each row's background and bottom border from the
row wrapper, so it read as track lanes. Lane visuals now live on the cells:
the sticky gutter keeps its own separator (header column stays delineated),
the time-mapped content div carries the row background + separator, and the
pad spacer stays transparent — bare shell background, no lines. The
new-track insertion line also starts at the pad's end instead of crossing it.
* fix(studio): no vertical line in the ruler band before 00:00
The ruler corner's right border drew the header-boundary line through the
ruler strip, so the band didn't read as starting at 00:00. Dropped it — the
boundary line belongs to the track rows below; the ruler stays completely
clean from the panel edge to the first tick, matching the empty left pad.
* refactor(studio): remove the timeline z-override badge
User decision: the "z" chip on clips never earned its place — dropped
entirely (timelineZOverride.ts + test deleted, TimelineClip badge rendering
and the zOverrideKeys derivation/threading removed). This also eliminates the
review's D2 finding at the root: the badge's cross-document comparison
(stackingContextId ?? null collides across source files in the expanded view)
produced false positives, and there is no longer a detector to mis-fire.
overlapsInTime/paintsAbove lose their export (the badge was their only
external consumer); the paint-order predicate itself is unchanged.
* fix(studio): collision-free expanded child lanes and host-window gap floors
Review findings D1 (blocker) and 4.
- D1: buildChildElements assigned expanded children synthetic display rows as
`host.track + index` — integers that can EQUAL a real clip's lane in another
file (host on 0 with two children puts child #2 on 1). Lane grouping merges
purely by track number, so the collision fused clips from different source
files into one display lane, and lane-scoped actions (the gap menu) then
batch-persisted a foreign file's clip. Children now take FRACTIONS strictly
between the host's lane and the next integer — structurally unable to
collide with any normalized lane, while still rendering as ordered rows
under the host. Regression test pins the reviewer's exact two-file scenario.
- Finding 4: gap math compacted toward absolute 0, but an expanded child's
display time is host-anchored — close/compact could drag it before its host
window and persist a wrong (even negative) local time. All gap functions
now take a lane FLOOR (laneGapFloor: 0 for ordinary lanes, the children's
expandedParentStart for child lanes — single-origin per lane post-D1),
threaded through the menu model, hover highlights, selected-lane strips,
and both commits. Close-gap shifts clamp at the gap's own left edge.
* fix(studio): scope mirror references, insert writes, and crossed-neighbor identity
Review findings 1, 2, and 3.
- Finding 1: buildTrackInsertEdits normalized the FULL display set and
persisted every shifted clip — writing host-lane numbers into OTHER
composition files when expanded children were showing. The renumber write
set is now the edited element's own source file (the sanctioned multi-write
converges one FILE to lane space, never neighbors' files); foreign clips
keep their authored tracks and re-derive display lanes. The locked-clip
refusal scopes the same way. Expanded-origin elements refuse the insert
outright (a new lane is a host-space renumber, meaningless in the child's
file), and the mirrors restrict an expanded child's lane candidates to its
own siblings' lanes — a sub-comp child still mirrors WITHIN its sub-comp
(persisting the sibling's authored track) but can never land on a host lane
with no same-file occupant. authoredTrackForLane's offset fallback rounds:
fractional synthetic rows must never leak fractions into data-track-index.
- Finding 2: the mirror comparison sets required only sameSourceFile, but a
file can contain several CSS stacking contexts and leaf z is only
comparable within one. Both resolvers now scope by samePaintScope — same
source file AND same stackingContextId (the file check also stops null root
contexts of different files from comparing equal in the expanded view).
- Finding 3: the crossed-neighbor key was derived without selectorIndex, so
duplicate class selectors (.sub) resolved to occurrence 0 — a different
clip. The key now carries getSelectorIndex, matching how z-reorder entries
derive theirs.
* fix(studio): z-to-lane gestures are one serialized transaction gated on durable persists
Review findings 5 and 7.
- Finding 5: commitDomEditPatchBatches resolved successfully even when the
server matched NO patch target — the z write never reached disk (the
preview reloads to reconverge) yet the lane mirror still ran, desyncing
track order from what actually paints. The commit now resolves a durability
report ({allMatched, changed}; the save queue and commit types are generic
over the result), and the mirror phase is skipped on allMatched === false.
- Finding 7: the z persist rides the DOM-edit save queue while the lane move
rides the timeline/SDK path — two queues, so a second rapid gesture's z
write could land BETWEEN the first gesture's z and lane phases. Every
z-to-lane gesture (canvas z-order menu AND Layers-panel drag) now runs
through runZLaneGesture: a single module-level tail that serializes the
COMPLETE two-phase transaction, with unit tests for ordering, the
durability gate, and queue resilience to failed gestures. The timeline
lane-drag's inverse (move-then-z-sync) shares its phases' await ordering
already; cross-gesture serialization for that path is noted as follow-up.
- LayersPanel's pure sort helpers moved to layersPanelSort.ts (600-line cap).
* fix(studio): multi-clip GSAP batch mutations roll back on late failure
Review finding 6. finishGroupTimingGsapFallback mutates files sequentially
per clip; a late per-clip failure left the earlier rewrites on disk with no
aggregate history entry — unreachable by undo. foldGsapMutationIntoHistory
already snapshots every touched path before mutating; on a mutation failure
it now restores each path whose disk content changed (all-or-nothing batch),
reports restore errors without masking the original failure, and rethrows.
Regression test drives a two-clip batch whose second rewrite fails and
asserts the first clip's write is restored byte-identically.
* fix(studio): scope mirror inserts to their lane zone
* fix(studio): unify source-scoped clip identity
* fix(studio): isolate track insert topology
* fix(studio): harden timeline paint synchronization
---------
Co-authored-by: Miguel Angel Simon Sierra <miguel.sierra@heygen.com>
Review 1 (restore commit):
- asset reveal now clears any open preview overlay (stuck-overlay repro:
preview on A, click already-added B — A stayed open over the reveal)
- duration readout rolls back on failed persist: captureDurationRollback
snapshots store + live root data-duration before the optimistic sync and
restores both in every move/resize/delete/group catch (golden's
previousDuration pattern)
- asset preview opened during running playback dismisses immediately (the
RAF loop bypasses the store, so the subscription alone never fired)
- persistTimelineBatchEdit resolves the target (findTagByTarget) before
treating identical output as a no-op — a mistargeted member now throws
like the single-element path instead of being silently dropped
- a post-mutation history-fold failure no longer suppresses the preview
sync: fold errors are surfaced separately and the rewritten script still
syncs (previously the preview kept stale GSAP positions with no recovery)
- timelineRevealScroll guards degenerate viewports (windowSize <= 0)
- CodeQL: encodeURIComponent(projectId) at all timelineTimingSync fetches
Review 2 (single-source-of-truth pass):
- createTimelineElementFromManifestClip — the one manifest->element
boundary — now carries authoredTrack and stackingContextId; expanded
sub-comp children preserve both (authoredTrack in their OWN file's space)
- authoredTrackForLane scopes occupants to the dragged clip's sourceFile
(a foreign file's authored values are a different coordinate space);
nearest-same-file-lane offset fallback
- optimistic store updates mirror the persisted track into authoredTrack
(and roll it back on failure), so consecutive drags before a reload
resolve from fresh data
- spill sub-lanes: documented decision — dropping onto a spill lane is a
legitimate same-track join (occupants share the authored track by
construction); false 'never a lane-move target' docstring rewritten
- single-element fallback persists vertical-only moves (early return now
requires neither start nor track changed; live DOM patch includes
data-track-index)
- canonical contextKey helper for stacking-context normalization
- new pipeline test crosses the REAL factory boundary (sparse authored
tracks -> factory -> expansion -> normalize -> drag commit -> persisted
attribute), no injected fields
Two legibility fixes for the canvas z-order menu, from user feel-testing:
- z-only commits no longer remount the preview iframe. The commit hook
already applies the inline z (+ injected position) to the live elements and
updates the store synchronously; the post-commit reloadPreview() was a
redundant full remount that read as a canvas 'blink' on every action.
commitDomEditPatchBatches gains skipReload, engaged only when provably
safe: every op is an inline-style patch AND the server reports every patch
matched — anything else falls back to the reload so the preview reconverges
with disk. The file-watcher's own reload stays suppressed by the existing
domEditSaveTimestampRef window, so the skip is real.
- Bring Forward / Send Backward step over the next VISIBLY overlapping
sibling. The nearest z-neighbor in a composition is often invisible at the
current frame (runtime hides time-inactive clips with inline
visibility/display; GSAP parks elements at opacity 0), so the step crossed
something the user couldn't see — 'enabled but nothing happens'. The
forward/backward set now filters on element-level computed visibility
(display/visibility/opacity, injectable for tests); enable/disable shares
the resolver so the menu is honest: actions disable when no visible
neighbor exists. Front/back keep the full painting family.
- The neighbor that was stepped over gets a 600ms accent flash, drawn in the
studio overlay layer (never in the iframe DOM), so the action shows its
work.
An adversarial review of the canvas context-menu z-order pipeline (Bring to
Front / Forward / Backward / Send to Back) found the resolver math sound but
the glue between the menu and the commit hook broken:
- The menu optimistically wrote style.zIndex AND position: relative to the
live elements BEFORE the commit hook ran. The hook decides whether to
persist position by checking getComputedStyle(el).position === 'static' —
always false after the pre-apply — so the position patch was never
persisted on the menu path and the reorder silently reverted at the
post-commit reload for any nested/static element (root clips survive only
because the runtime forces position:absolute). The same pre-apply made the
failure rollback capture the already-mutated values, restoring the broken
state on persist errors. The menu no longer pre-applies; the hook owns the
live writes (it already applied both synchronously) and now sees true
priors. Siblings without a persistable identity still get their z applied
live-only so a renumber stays visually coherent.
- The commit hook's entry.key store-sync plumbing had zero production
callers; the store zIndex went stale until full reload. All three callers
(canvas menu via PreviewOverlays, timeline lane z-sync, LayersPanel) now
derive and pass the timeline store key (new deriveTimelineStoreKey helper).
- patchElementBatch discarded the server's per-patch matched[]; unresolvable
siblings persisted partially and silently. Unmatched targets now warn and
report save-failure telemetry (z-reorder-unmatched) without rolling back
the matched subset.
- template/noscript elements counted as painting siblings, so renumber
fallbacks wrote z-index/position into <template> tags in the source file.
Excluded from the sibling family.
- The default undo coalesce key merged DISTINCT z actions within 300ms into
one undo entry; the action kind is now part of the key (LayersPanel drags
keep coalescing within a drag; explicit lane-move gesture keys untouched).
- rectsIntersect comment claimed touching rects intersect; the strict
inequalities say otherwise — comment fixed.
Vertical clip moves committed in the store but never survived: two persist
bugs plus a runtime renumber all fought the stable-track-lanes model.
- timelineMoveAdapter deliberately stripped the track from lane-reorder
persists ('z-only reorder path' — the old z-driven lane model). Lane =
authored data-track-index now: lane-reorder and track-insert both persist
the track; plain timing moves omit it to stay SDK-fast-path eligible.
- Display lanes and file tracks are different coordinate spaces:
normalizeToZones packs sparse authored tracks (1,2,... or gaps, or DOM-index
fallbacks) onto contiguous display lanes, and lane edits persisted the LANE
number — silently re-targeting the wrong row in any non-0-contiguous file.
Elements now record their authoredTrack when remapped; a lane change
persists the target lane's authored track (store stays in lane space).
- The runtime split same-track clips of different kinds (video vs caption
div) onto separate renumbered tracks at discovery, so authored indices
never round-tripped ('drop onto an existing track' bounced back). Removed:
data-track-index is honored verbatim (render never reads it); kind-based
row presentation belongs in the display layer if ever wanted.
Adversarial review fixes on the same pipeline:
- runtime: parseInt(attr) || fallback dropped authored track 0 for GSAP and
overlay clips (parseAuthoredTrack helper honors 0)
- single-clip move fallback persisted only data-start — lane changes snapped
back on reload (now passes the track to the patch builder)
- lane-change z-sync candidate ignored a multi-selection's time shift, so
patches were computed against stale overlap sets
- track insert around a locked clip persisted a colliding renumber (the next
normalize merged lanes); the insert is now refused with a warning
- computeStackingPatches compared leaf z across CSS stacking contexts, where
ancestor z decides paint order; the sync now partitions by
stackingContextId and never patches across contexts
Timeline geometry (user-reported):
- fit zoom leaves 20% trailing headroom (FIT_ZOOM_HEADROOM in
timelineLayout.ts; single fit-pps source, so ruler/lanes/playhead/drag all
inherit it)
- playhead line center now sits exactly on GUTTER + t*pps at every zoom
(wrapper had shrink-wrapped to the 9px diamond, off-centering the line);
ruler ticks center on their timestamp
- ruler: frame-mode steps snap to whole frames (no duplicate labels), hour
steps added for far zoom-out, tick positions computed as exact multiples
(no float drift)
The Studio stack rebuild (#2291) landed the remaining NLE layers but dropped
or regressed several final-wave behaviors from the reviewed studio-dnd stack,
and never repaired the stale timelineZones.ts that #2279 introduced. Restores:
- TimelineRuler: sticky under vertical scroll, full-height gridlines removed
(beat lines only), frame-number tick labels via a persisted timeDisplayMode
store preference (PlayerControls toggle now store-backed)
- timelineZones: stable track lanes — lane = authored data-track-index
ascending; z is paint order only (replaces the stale z-driven lane pack,
which broke track insert-band commits that contractually depend on it)
- persistTimelineBatchEdit: a batch member whose patch is a no-op (attributes
already at target values, e.g. in a track-insert renumber) is skipped
instead of aborting and rolling back the whole batch — this alone made
new-track creation (incl. the top insert band) fail silently
- useTimelineStackingSync: unresolvable clips read as NaN again so
timelineStackingSync's Number.isFinite exclusion contract holds (z=0
fabrications skewed stacking boundaries)
- timelineAssetDrop: drops land on the drop track (no overlap bump to
max-track+1), data-hf-id stamped, audio gets data-volume
- timing edits: soft-reload the server's rewritten GSAP script instead of a
full iframe remount (no all-clips flash on move/resize); full reload only
when no scriptText or the soft path can't apply, and one full reload when a
group edit touches non-active files (new hooks/timelineTimingSync.ts)
- duration: content-driven grow-AND-shrink on move/resize/delete, synced
optimistically to the store and the live root data-duration at release
(was a grow-only ratchet; shrink never updated the readout)
New UX: sidebar asset click opens a compact non-modal preview over the canvas
(dismiss on outside click, Escape, playback, or seek), and clicking an
already-added asset reveals its clip in the timeline (smooth minimal scroll
to its time and lane; vertical-only in fit zoom).
Verified by pointer-driving a real project: sticky ruler + gridline removal,
no iframe remount on move/resize (marker survives, GSAP tween positions
rewritten in place), duration readout 40->37->40 on shrink/stretch, and
top-insert-band track creation renumbering lanes correctly on disk.
What: new pure module timelineCollision — zone-aware drop placement
(clampTrackToZone, resolveZoneDropPlacement, resolveInsertRow,
resolvePlacement, lane/overlap predicates) with its full test suite.
Why: the no-overlap core of the NLE clip-drag engine; plain functions, no
DOM, no React, no store writes.
How: new files only; type-only imports from the existing playerStore.
First runtime consumer arrives with the drag-engine PRs.
Test plan: bunx vitest run timelineCollision.test.ts; tsc --noEmit; fallow
audit clean (all exports test-consumed).
* feat(studio): timeline leaf helpers — audio inspector, zoom math, UI prefs
What: extends three leaf modules to their final NLE-stack form, tests in the
same change: timelineInspector (isAudioTimelineElement, resolveBeatSourceTrack),
timelineZoom (zoom/pps math incl. computePinnedZoomPercent), and
studioUiPreferences (persisted editor prefs).
Why: leaf dependencies of the NLE timeline stack; landing them first keeps
the later glue PRs to wiring.
How: additive from the consumer side — every export main already uses is
unchanged (typecheck against main's consumers passes untouched); every new
export is exercised by a test in this PR.
Test plan: bunx vitest run on the three test files; tsc --noEmit in
packages/studio; fallow audit --base origin/main clean.
* feat(studio): seek-restore contract for player reloads
What: useTimelineSyncCallbacks gains resolveReloadSeekTime and revealIframe —
the pure contract for where the playhead lands after a preview reload
(pending seek > deep-link seek > store playhead, clamped) and for undoing
refreshPlayer's iframe hide. Test suite included.
Why: the NLE editor reloads the preview on every committed edit; this
contract is the difference between "playhead restores" and "jumps to 0".
How: additive exports on an existing hook file; main's consumers unchanged.
Test plan: bunx vitest run useTimelineSyncCallbacks.test.ts; tsc --noEmit in
packages/studio; fallow audit clean.
What: extends three leaf modules to their final NLE-stack form, tests in the
same change: timelineInspector (isAudioTimelineElement, resolveBeatSourceTrack),
timelineZoom (zoom/pps math incl. computePinnedZoomPercent), and
studioUiPreferences (persisted editor prefs).
Why: leaf dependencies of the NLE timeline stack; landing them first keeps
the later glue PRs to wiring.
How: additive from the consumer side — every export main already uses is
unchanged (typecheck against main's consumers passes untouched); every new
export is exercised by a test in this PR.
Test plan: bunx vitest run on the three test files; tsc --noEmit in
packages/studio; fallow audit --base origin/main clean.
* fix(skill): all file paths use capture/ subfolder prefix
Step-1 was updated to capture into <project-dir>/capture/ but all
file-read instructions across steps 1-6 still used bare paths
(extracted/tokens.json, assets/hero.png). Agents following the skill
looked for files in wrong locations, producing broken compositions
with 404'd images and fonts.
- step-1: all 12+ file-read paths prefixed with capture/
- step-2: tokens.json and asset-descriptions.md paths fixed
- step-3: visible-text.txt path fixed
- step-4: asset-descriptions.md, asset examples, directory tree expanded
to show capture/ children (screenshots/, assets/, extracted/)
- step-5: minor cleanup
- step-6: asset-descriptions.md path fixed, composition examples already
correct (../capture/assets/)
- techniques.md: Lottie, video, font paths all prefixed
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
* fix(skill): address Copilot review — font comment path, add videos/ to tree
- techniques.md: comment says ../capture/assets/fonts/ (matches composition context)
- step-4 file tree: add videos/ under capture/assets/
---------
Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Ular Kimsanov