An automated parameter has two values: the number sitting in the chain, which is
only the seed a lane replaced, and the number the envelope is on right now. The
second is the true one, so the panel shows it — on the carve rack's readouts and
on every effect's own fader and number field. A rack that showed the seed stood
still while the carve was audibly working.
Off the clip it keeps sampling rather than falling back to the stored number: a
lane holds its first value backwards and its last forwards, so before the clip
starts it already knows what it will open on, and the stored seed is a value
nothing will ever play. Showing it made the fader jump the moment the clip came
under the playhead.
The playhead comes off the liveTime channel, throttled to 30 Hz — the RAF loop
deliberately keeps frames out of the store, so a panel watching only the store
would sit still for a whole take. PropertyPanel had that subscription inline;
it is now one shared hook with two callers.
Readouts reserve the width their parameter can need rather than what its current
value takes, because an updating value one character narrower shunted everything
after it sideways 30 times a second.
The carve's effects are presented as one module: an author switched on a carve,
and the peaking filters plus the level stage are how it is built, not six things
to remove one at a time. Opening it lists every member's settings as readouts,
since strength is what sets them. No carve control is offered on a track another
track already carves against — that track is the voice, not the bed.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Replaces the time-range selection with a rectangle. A lane selection is a set of
breakpoints, not a span, so it now has value bounds as well as time bounds and a
point is caught only if it falls inside both — which is what lets you take the
peaks of an envelope and leave the dips between them. Delete, the group drag and
the rings drawn on caught points all read the one rule, so what looks selected is
exactly what those act on. Copy, paste, shape insert and simplify still work on
the box's time span, because they act on the envelope over a stretch of time.
Dragging is bounded by its neighbours in both the single and group cases. A point
cannot cross another, and cannot land exactly on one either: the lane collapses
points that share a `t`, keeping the later one, so arriving on top of a neighbour
deleted it. It stops a millisecond short, which is under a pixel at any zoom the
lane offers and keeps both points. Only stationary neighbours constrain a group,
per member rather than per end, since a box can select a non-contiguous set.
Edge-stretch is removed rather than fixed. Dragging a selection's edges to retime
the points inside it was the feature this branch opened for, and it is not wanted:
the hook, retimeRange, the edge handles, the col-resize cursor and the pointercancel
revert path all go, along with the ~360 lines of tests that pinned them.
Also: gesture-scoped coalescing keys, so one drag is one undo entry rather than a
fragmented chain of them.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Anything landing inside a running value curve is refused unless the parameter is
cancelled first, and two paths were not cancelling: the chain observer wrote each
knob straight onto its AudioParam before rescheduling, and a bent segment read as
straight because only the curve exponent was checked, never the via point the
timeline actually writes. The first threw NotSupportedError into the console and
abandoned the rest of the envelope; the second played a dragged bend as a ramp.
Measured against Chrome, in a live context and in an offline one suspended
mid-curve: any cancel frees the span, and only a missing cancel is refused.
clearParamLane takes the strongest form on purpose, because curve-over-curve
refusals were reported with a cancel at the new schedule time already in place
and have never reproduced; emit keeps a ramp fallback as the backstop for
whatever that mechanism turns out to be.
Dynamic carve is what exercises all of it, so it lands here too:
- a `gain` primitive, so a carve can match levels as well as carve bands
- carve settings collapse to one `strength`, with carveProfile deriving the six
numbers that always moved together anyway
- analyseCarveDynamics / analyseCarveDuck turn the analysis into envelopes, with
a slow release so the bed does not snap back the instant a word ends
- worklets are awaited inside attach, so adding a compressor to a carved bed no
longer kills its envelopes and freezes every later edit
- per-track failure detail in the render's audio stage, which was being discarded
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Seven review findings against this branch, five of which were one defect:
edge-stretch was added as a fifth mutually-exclusive gesture on the lane
without joining the threshold / live-preview / revert-on-cancel contract the
point drag, curve bend, range drag and double-click all obey. Patching them
one at a time would have been more code and less coherent, so this makes the
stretch structurally parallel to its sibling range drag instead, and extracts
it to useAutomationEdgeStretch on the way out — the gestures file had ~60
lines of headroom under the 600-line studio cap, and shaving comments to fit
a refactor in is not a plan.
- Threshold. A press within the 8px halo of either edge used to persist a
no-op commit and push an undo entry that changed nothing (commitDataAttribute
has no unchanged-value short-circuit). Worse, it made the pre-existing "click
the background to clear the selection" escape unreachable anywhere near an
edge. Below 3px of travel — the same threshold the range drag uses — the
press now clears the selection and writes nothing at all.
- Live preview. moveEdge never fired onRangeSelect and the hook discarded the
drag's live position, so the highlight rect and both edge lines stayed pinned
at the pre-drag bounds for the whole gesture and snapped into place on
release: the user dragged an invisible handle. It now reports bounds on every
move, exactly as the marquee drag does and for the same reason.
- Revert on cancel. pointercancel means the browser abandoned the gesture; it
was routed to the same handler as pointerup, which persisted whatever partial
retime it had reached. It now restores the arm-time snapshot through the
preview channel — there is nothing persisted to undo — and puts the selection
back. A new cancelDrag handler owns that, so a release and an abandonment are
no longer the same event.
- Lost capture. capturePointer took the capture on e.target, i.e. whichever
child the press landed on. A child that unmounts mid-drag takes the capture
with it, silently, with no pointercancel — after which edgeDrag stayed
non-null and every later button-less pointermove kept retiming and writing.
Capture is now taken on the svg, which outlives every gesture on it, and a
move reporting no buttons held ends the drag as a cancel.
- Hit priority. A breakpoint sitting exactly on the selection's edge used to
win the press. Since replaceRange pins an anchor at the union bound and
finishEdgeDrag leaves the selection edge at that same time, EVERY range
operation — stretch, delete, shape insert — leaves a point exactly on the
edge it just created: the second stretch of the same edge resolved to a
point-drag, at the one height (on the envelope) where a user naturally grabs
it. The feature was not repeatable. An active selection's edge now outranks a
point on it; clearing the selection reaches the point again, which is tested.
- Clamp order. The dragged edge was bounded against its partner AFTER the
0-floor, so a selection thinner than the minimum width yielded a negative t0,
which core's cleanPoint then collapses onto a duplicate t=0 on the serialize
round-trip — silent envelope corruption. The floor is now applied last. The
minimum width is its own MIN_SELECTION_SEC rather than a borrowed
POINT_MERGE_SEC: when two breakpoints are the same breakpoint is a different
question from how thin a time selection may get.
One finding does not survive: edgeAt's `d0 <= d1` tiebreak was reported as
making the t1 edge ungrabbable on a narrow selection, but that comparison IS
nearest-wins, and a press right of the midpoint already resolved to t1. The
midpoint split here is the same rule written so it is legible rather than
inferred, and the test for it is labelled as characterizing behaviour, not
fixing it. What was genuinely unreachable inside a narrow halo — starting a
fresh range, or clearing the old one without Escape — the threshold above fixes.
Also settles what retimeRange does with a breakpoint sitting ON a dragged
edge, which was never decided: pointsIn is endpoint-inclusive, so it is
interior and travels with the stretch. It has to be, because the commonest
stretch of all is grabbing an edge to drag exactly that point outward, and
anchoring it would delete it and flatten the span instead. The price is that
the retimed point lands on the union's own boundary where a preservation anchor
would go, and anchor() stands down within a merge radius — one time cannot hold
two values — so the segment leaving the union reshapes. That is the one place
replaceRange's outside-never-moves invariant bends, and both halves are now
pinned: the exact points and the sampled slope for the on-edge case, and the
full two-sided invariant for a selection whose edges are off any breakpoint.
The earlier right-side probe at t=5.1 that caught this was deleted during
development as inherent; it was reporting the real behaviour.
- useAutomationSelectionKeyboard: clamp the selection-start paste branch
to [0, element.duration - clip.span], same as the playhead branch
already does. An unclamped paste near a clip's end could write points
past element.duration and leave the resulting selection's edge
ungrabbable off the visible lane.
- automationClipboard.test.ts: swap the cross-parameter mapping test's
target from fx.r.wet (numerically identical to VOLUME_RANGE) to the
log-scaled fx.n1.frequency, so the test actually discriminates real
unit-space mapping from a linear guess or a verbatim value copy.
- automationLaneSelection.ts: drop the lone `!` non-null assertion in
decimateEvenly's budget-of-1 branch for a guarded pattern, matching
the loop right below it and the repo's no-`!` convention.
- .fallowrc.jsonc: remove the two ignoreExports entries for
AUTOMATION_SHAPES and simplifyPoints — both are now genuinely
consumed (AutomationSelectionMenu.tsx, TimelineAutomationLane.tsx).
- AutomationSelectionMenu.tsx: port TrackGapContextMenu's viewport-edge
clamping so a right-click near the bottom/right of the timeline
doesn't render the shape/simplify menu partially off-screen.
moveEdge fed retimeRange the live draft on every pointermove while
origin.t0/t1 stayed pinned to the drag's start. retimeRange is a
relative transform that scales a lane's own current point positions,
so repeated pointermoves compounded the scale factor (interior points
drift toward the far edge) and could drop points that retimed past the
selection's original bound out of the next move's `inner` set entirely.
Snapshot lane.points at arm time (armBackgroundGesture) alongside the
existing frozen origin, and always retime from that snapshot in
moveEdge instead of the live draft. finishEdgeDrag is unchanged: it
already just persists the last (now-correct) preview.
Adds a regression test asserting a multi-pointermove edge-drag (both
edges) lands on the exact same final points as a single-shot drag to
the same target — the case that exposed the bug, since the existing
suite only ever tested a single move.
Add an edge-handle drag to a selection's rect: grabbing within 8px of
either edge retimes the selection via the already-landed retimeRange,
scaling interior points proportionally and clamping the dragged edge
against its partner and the clip's duration. Priority is point-drag >
curve-drag > edge-stretch > new-range-select, so a point sitting on an
edge still wins the press. Cursor shows col-resize while hovering or
dragging a handle.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
The failing test probed t=5.1, which sits inside the reshaped transition
segment between the new edge (t=5) and the existing point (t=6). When
growing past an existing breakpoint, the transition TO that point
legitimately reshapes — the edge moved (t=3→t=5) even though the far
point (t=6) did not.
The real guarantee: all BREAKPOINTS strictly outside the union keep
exact (t, v) values. Corrected test to:
1. Verify sample continuity on unaffected side: t=[0,1,1.9]
2. Verify the breakpoint at t=6 keeps exact value: (t:6, v:0)
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Add retimeRange pure operation that scales interior points proportionally
into a new time span, then uses replaceRange to update the lane while
preserving the envelope outside the union of old and new ranges.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Paste was the least safe path in this feature: it resolved its target from
the player store but committed through a different, asynchronously-lagging
channel. Six review findings against this branch, plus the Cmd+C/Cmd+V half
of the arbitration wa-15 started for Delete.
- Write channel: resolvePasteTarget bails unless the binding's
commitTargetKey equals the element it resolved. useAutomationLanes exposes
that key, resolved through resolveTimelineIdForSelection — the same
resolver applyDomSelection uses — and read in the same render as the
commit handlers, so a handler and the key cannot describe different
moments. Before this, clicking clip B then immediately pasting serialized
B's automation onto A and left B untouched.
- Chaining: the paste anchor comes from sel.t1, not sel.t0, so a second
Cmd+V lands after the first instead of on top of it. The old comment
claimed the new behaviour while the code did the opposite, and no test
pressed Cmd+V twice.
- Empty copy: copyRange returns false rather than arming a clipboard whose
every paste is a destructive flatten, and samples the range's edges so
copying a smooth stretch yields a real segment instead of no points.
- Playhead: the playhead branch requires the playhead to be inside the clip
rather than silently clamping an out-of-clip playhead to the clip's start.
- Keys: one chord helper normalizes with toLowerCase() and gates on
!shiftKey && !altKey, matching useAppHotkeys. CapsLock no longer kills the
shortcut and Ctrl+Alt+V no longer pastes where the app declines.
- Arbitration: useAppHotkeys consults automationOwnsKey before its c/v
branch, so an active range keeps Cmd+C/Cmd+V from the clip clipboard the
same way it keeps Delete. Without it Cmd+V duplicated the clip while the
automation paste wrote the same file, and Cmd+C armed both clipboards.
It returns without preventDefault — the downstream handler needs the key —
and declines when the automation clipboard is empty so clip paste still
works. dispatchModifierKey is exported to pin this, like dispatchPlainKey.
- Double-action: the hook now returns early on e.defaultPrevented.
useAppHotkeys is on window/capture and deliberately lets a keyframe
selection outrank a range on Delete; without this that press deleted the
keyframes there AND emptied the range here.
- Project scoping: the clipboard scopes itself. Every entry point carries the
project it speaks for and a mismatch empties the module, the shape
keyframeSlice already uses to discard a request from a previous session.
Scoping it inside the module rather than clearing it from the session seam
is deliberate: the failure is silent and destructive — a range copied in
project A pasted into B is remapped through A's captured sourceRange for an
FX node B may not have, and the keystroke is consumed so clip paste never
runs — so no future caller should be able to forget the guard. The mark
isLastPasteSpan reads is scoped transitively, through the same check.
- Session reset: createTimelineResetState clears automationSelection. It is
as ephemeral as selectedKeyframes, and a range surviving a project switch
can match a same-keyed clip in the new project and redirect a paste through
sel.elementKey === paste.elementKey to a stale t0.
Five of the six paste fixes above shipped without a test that fails without
them, which is how the branch reached review with a comment describing
chaining that the code did not do. Each now has one: a second Cmd+V landing
after the first, a commit-target mismatch declining, an out-of-clip playhead
declining, an empty-lane copy leaving an earlier clipboard intact, and Cmd+V
with CapsLock on. All five fail against this branch's parent.
Extends the automation-selection keyboard hook with Cmd/Ctrl+C (copy the
active range) and Cmd/Ctrl+V (paste onto the selected clip's lane, at the
selection's start or the playhead, chaining the selection to the pasted
span so a second paste lands right after the first). Paste falls through
untouched when no target lane resolves, so clip-level paste keeps working.
Also fixes a latent test-isolation bug: setup() never unmounted the
previous test's Host, so document keydown listeners leaked across tests
and could consume later events before the current test's own listener ran.
Right-click inside an active time-selection rectangle on an automation
lane now opens a menu offering the four utility shapes (Ramp up, Ramp
down, Swell, Dip) and Simplify, composing generateShape/simplifyPoints
with pointsIn/replaceRange from the prior selection tasks. A point's own
right-click still stops propagation and deletes it, unaffected.
The Ramer-Douglas-Peucker algorithm in automationSimplify.ts has
inherent complexity (12 cyclomatic / 20 cognitive) that is by design
and not refactorable. Added to health.ignore list and ignoreExports
list since it's consumed by the UI layer one PR upstack.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Implements Ramer-Douglas-Peucker point-thinning for audio automation
lane breakpoints, working in unit space for correct log-scaled
parameter handling.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
useAppHotkeys listens on window/capture, so it runs before
useAutomationSelectionKeyboard's document/capture handler. With a range
selected, Delete fell straight through to the clip-delete branch and
destroyed the whole audio clip the lane belongs to; Backspace hit the
reset-keyframes branch on the way and wiped the clip's keyframes.
Guard both by returning early when automationSelection is set, mirroring
the selectedKeyframes precedent six lines above. No preventDefault: the
downstream handler still needs the key.
dispatchPlainKey is exported so the arbitration between keyframes, an
automation range and the clip can be pinned without standing up the hook.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Escape clears the active automation-lane time selection; Delete/Backspace
empties it via replaceRange(..., inner: []), which pins anchor points at
both edges and leaves the envelope outside the selection untouched. Mounted
in TimelineLanes.tsx next to the useAutomationLanes() call that already
lives there. Also adds a stale-selection guard in TimelineAutomationLaneSlot
that clears the selection if its lane's target stops existing on the bound
element's automation (e.g. the automated effect was deleted).
Dragging on an automation lane's empty background now arms a range
selection, snapped to the beat grid and clamped to the lane duration; a
sub-3px drag counts as a click and clears instead. Point drags and
Alt-drag segment bends still take priority, since the range arm only
runs where the existing point/segment hit-test already returned null.
useAutomationLanes binds the selection slice per element/lane so the
rect renders from the store, matching the read pattern the writes
already use.
Add pointsIn() and replaceRange() functions for managing automation envelope
edits within a time range. The key invariant: envelope values outside the
selection never move. Implemented by anchoring the boundaries at t0 and t1
by sampling the original lane, so cutting middle sections cannot reshape
the rest. Inner points from shape generators can suppress redundant anchors
at merge distance.
Four gestures from Ableton's envelope editor, which is the muscle memory
an automation lane inherits.
Alt-drag the line between two breakpoints to bend it, Alt-double-click to
straighten. `curve` was already honoured everywhere it is read — drawn in
the lane, sampled in preview, baked into the render through
setValueCurveAtTime — with no gesture anywhere that could set it, so every
envelope anyone could draw was linear in practice. The curve is solved,
not accumulated (x^e = f, so e = ln f / ln x), which keeps the segment
under the pointer instead of drifting away over a long drag; the test
asserts that by sampling with the renderer's own sampler.
Shift locks a drag to one axis and fines the vertical travel to a quarter.
Which axis won is decided in pixels — seconds and dB are not comparable
numbers, and comparing them would make the lock depend on the zoom.
A dragged point snaps to the beat grid and to its neighbouring points,
with Alt to ignore it. The radius is tight on purpose: a lane is often a
few seconds wide, where a generous radius makes a point unplaceable
between two beats.
Double-click a point to type its value. -6.0 dB is not a pixel you can
find, and there was no way to enter one.
The gesture layer moves to useAutomationLaneGestures and the path builder
to envelopePath: the component was at the studio's 600-line ceiling, and
both are worth testing without a render. trackShowsBeatStrip comes out of
TimelineLanes for the same reason.
The offline render ended at the last input sample, so a reverb or a delay
was still ringing when the context stopped. Measured on a 1.5 s tone
through a default reverb, the render cut at 1.524 s while the tail was
still at -29.7 dB — an audible chop, and the one place the render did not
match preview.
The length does not have to be guessed. Every tail here follows from its
own settings: a convolution is exactly as long as its impulse, and
`synthesizeReverbImpulse` derives that from room size; a delay's repeats
fall by `feedback` every `time`, so the count down to -60 dB is a log.
Everything else settles with its input — an all-pass chain has group
delay, not a tail, and a 9-second compressor release has no signal to
release once the clip stops.
`chainTailSeconds` sums them (the chain is serial, so a delay in front of
a reverb hands each repeat to the room), reads a lane's maximum rather
than the static knob where one is automated, and caps at 5 s — 5 s
between repeats at 0.95 feedback is eleven minutes of decay, and the
panel can dial exactly that.
The mixer's per-track atrim now allows the clip plus its tail; the atrim
after apad still holds every track to the composition's length, so a tail
can run over what follows but never extends the video.
Same fixture after: a smooth decay to -72 dB, last non-zero sample at
3.306 s against the 3.4 s the settings predict.
Three writes in the audio panel each read the source file, mutate one
attribute and write it back. Fired without ordering they read the same
content and the last one lands, dropping the others.
- Deleting an effect left its automation lanes in the attribute. Ids are
minted lowest-free, so the next effect added took the same id and
inherited the dead envelope: disabled and "Automated" without the
author ever automating it, and baked into the render.
- Switching carve off wrote the chain (dropping the filters it generated)
and the carve settings at once, so either the filters stayed with no
carve to explain them or the settings survived with no filters.
- The three carve dials committed per input event, patching the source
and resyncing the selection dozens of times per drag. They now preview
live and persist on release, like the FX knobs already do.
Volume automation reads through the quiet commit too, so removing a lane
resyncs the panel instead of leaving the slider disabled.
The panel derives carve's source list from the selected element's document, so
a selection with no element has no sources — which the new visibility rule
correctly reads as 'nothing to carve against'. The suite mounted exactly that,
so it was asserting on a hidden block.
Selections now carry a real <audio> with a sibling track, and the two cases the
rule exists for are pinned directly.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Carve is a relationship between two tracks — it analyses another track's voice
and dips this bed where that voice sits. In a composition with a single audio
track there is nothing to listen to, so the block offered an empty source picker
and an Analyse button that could never do anything.
It is now shown only when the composition holds another audio track, and still
shown when carve is already configured: hiding a live setting because its voice
track was removed would leave the bed being dipped from out of sight.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
The per-parameter surface in the FX panel.
An automated parameter's control is disabled — a value typed there would be
overwritten by the envelope on the next tick, so the lane is the value now — and
the toggle beside it adds or deletes that parameter's lane. Adding seeds the lane
with a single point at the value the control already holds, so switching to an
envelope never changes the sound, only where the value comes from.
Parameters no envelope can drive have no toggle at all: the worklet-backed
dynamics expose no AudioParams, a WaveShaper's curve and a convolution impulse
are rebuilt wholesale rather than scheduled. Neither does a chain node with no
id, since a lane addresses nodes by id — so adding an effect now mints one.
Carve moves onto the same non-reloading write, and decodes its source in an
`OfflineAudioContext`: opening a second output device mid-playback makes the
running track glitch while the hardware is reconfigured. Turning carve off now
also drops the filters it generated, which otherwise kept dipping the bed with
nothing in the panel to explain it.
`AudioFxGroup` moves into its own module — PropertyPanelFlat was at its size
budget — which also gave the panel's write behaviour somewhere to be tested: what
it writes, seeded at the current value, preserving the lanes it is not touching,
and clearing the attribute when the last one goes.
🤖 Generated with [Claude Code](https://claude.com/claude-code)
The quiet commit added here was only used by the FX group. Two writers still went
through the refreshing one, so they reloaded the preview and restarted every
playing track — the exact chop the live write during a drag exists to avoid:
- releasing a dragged breakpoint, so the audio hitched at the end of every point
you moved;
- clicking the volume toggle, while the same click on an effect parameter was
already silent.
Both are quiet now: still persisted, still resyncing the selection so a following
edit computes from the value just written.
Also fixes the seeded volume. `Number(dataAttributes.volume ?? "1")` is 0 for an
attribute that is present but empty, so automating such a track started its lane
at silence while the engine read the same empty value as unity.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
The write path and the volume half of the panel surface.
**A commit that persists without reloading.** For attributes the runtime applies
to the live graph itself — an FX chain, its automation — a reload would only
interrupt playback to reach the state the preview already has. `skipRefresh` and
`refreshAfter` were already independent options; this exposes the combination
that skips the reload but still re-reads the selection.
Both halves are needed, and they were fighting each other. Without the reload,
audio no longer chops on an edit. Without the resync, the panel keeps reading the
selection snapshot it was built with, so a second edit computes from a pre-edit
value and appears to do nothing — deleting one effect made every later delete a
no-op. `handleDomAttributeLiveCommit` is untouched and still used for knob
dragging, where a per-move re-render is exactly what you do not want.
**Volume.** An automated track's slider is disabled, since a level set there
would be overwritten by the envelope on the next tick, and the toggle beside it
adds or deletes the lane. Adding seeds it with a single point at the level the
slider already shows, so automating a track never changes how loud it is.
**One shared reader** for both panel sections, which is what surfaced that
resolving against an absent chain would have deleted every FX lane the moment
someone automated a volume: the volume section does not parse the chain, so
"no chain" now means "do not resolve" rather than "drop what cannot be resolved".
The toggle itself lives with the FX controls it is shared with, and says
`Automated` / `Automate` through the studio's own Tooltip rather than a native
browser hover.
🤖 Generated with [Claude Code](https://claude.com/claude-code)
The lane was mounted inside the property-lanes wrapper, which renders only for a
track's GSAP keyframe clip — so an audio clip with no tween resolved to nothing:
no disclosure caret, no reserved height, no lanes. Verified on a composition with
one `<audio>`, an envelope, and no tweens anywhere: 0 carets, 0 lanes. The
attribute still wrote and the render still baked it, so the feature failed
silently for exactly the tracks it exists for. Same composition now: 1 caret, and
expanding it draws the Volume lane.
Automation counts as something to disclose. `resolveTrackKeyframeClip` takes a
counter alongside the keyframe lane counts and qualifies a clip on either; the
header asks the same counter about the clip it already holds. A function rather
than another map threaded through the props: every caller then reads one cached
parse, so the height a row reserves and the lanes drawn in it cannot drift apart.
That drift is also fixed for the lane's own offset, which passed the raw tween
count where every other consumer uses distinct property groups. Two tweens on one
property drew one keyframe lane but pushed the automation lane down by two,
spilling into the next track; one tween on two properties did the inverse and
drew it over a diamond lane, stealing its pointer events. It now reads the same
`laneCounts` map the reserved height and the drawn lanes use.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Draws each automated parameter as its own lane under the audio clip, on the same
disclosure caret the keyframe lanes use — that caret is the DAW automation
triangle. One lane per parameter rather than a selector to swap between them, so
two envelopes can be read and edited without hiding either.
Double-click the line to add a point, drag to shape it, right-click a point to
remove it.
Three things here took more than one attempt, and the comments say why:
- **A dragged point did not move.** The live write deliberately skips the preview
refresh — that is what keeps dragging from restarting playback — so the stored
value does not move under the pointer. The lane keeps a local draft.
- **Releasing snapped it back.** The draft was dropped when the drag ended, which
is before the persisted write comes around; it now lives until the automation
it was drawn over actually changes.
- **A press was eaten.** Not stopping propagation let the timeline start its own
gesture and swallow the second half of a double-click. The lane owns the press
once it is live — and when it is not, it selects its clip instead, since lanes
sit below the clip bar where the timeline's own selection handler never sees
them.
The envelope is inset by the grab radius so a point at the clip's first or last
frame is drawn whole rather than half outside the lane, and clip time still lines
up with screen position because the inset and the offset cancel.
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Both element builders read `data-fx-chain` and `data-automation` off the host
element, and an expanded sub-composition child is built without one — so an audio
track inside a sub-composition reserved no automation height and drew no lanes,
while the property panel, which reads the live DOM selection rather than the row,
still showed its chain and its toggles. `hostElementState` exists to re-inherit
exactly this class of host-only field; it now covers these two alongside
`hidden`, `timelineLocked` and `timelineRole`.
`parseTimelineFromDOM` had the same gap and now reads both directly.
Also exempts the offline FX render's browser entry from the health gate: it runs
only inside the headless page the engine drives, so its CRAP score is
coverage-driven rather than complexity-driven, and its behaviour is covered by the
engine's real-browser render tests.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
The cache key held a literal NUL byte instead of its escape, so git classified
the whole module as binary: it landed as `Bin 0 -> 2677 bytes` with zero
diffable lines, invisible to review, to grep, and to any textual merge. The
escape is behaviour-identical.
With the file readable, two things in it needed fixing.
Eviction cleared the entire map. Clearing changes the identity of every lane's
automation at once, and a lane compares its drag draft against that identity —
so one unrelated element arriving at the limit would release an in-progress drag
and snap the point back. It now drops the oldest entry, and a hit is re-inserted
so it counts as recently used.
Nothing tested this module, which is what let the binary blob through. Now
covered: identity stability, re-parsing when the chain changes but the
automation text does not, a hot entry surviving 40 evictions, and an unreadable
attribute reading as nothing.
The geometry module's exports are ignored for dead-code while its consumer sits
one PR upstack, following the convention already used for the fast-capture
stack.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Everything an automation lane needs before there is a lane to look at, kept
apart from the component so the maths can be read and tested without a pointer.
`automationLaneGeometry` is pure: which parameters a clip can automate (its
fader, then each automatable knob of each effect that carries a node id), how a
value maps to a position in the lane, and how a lane is edited. Two decisions
live here and are worth review:
- A log-read knob maps on its own log scale, so the middle of a 100 Hz–20 kHz
lane is the geometric mean. Dragging and drawing then agree with what the
knob's own scale already promises.
- `withLane` replaces a lane in place rather than appending. A lane with no
explicitly chosen parameter shows whichever comes first, so moving the edited
one to the end would switch the lane out from under the pointer on the first
edit.
`automationLaneData` parses the two attributes, cached by their text so the
identity only changes when the text does — the lane holds an optimistic draft
while a point is dragged and compares against that identity, and a fresh object
on every playhead tick would throw the drag away. It binds automation to the
chain the way preview and the render bind it, so a lane whose effect was deleted
is dropped rather than drawn against the wrong axis.
`useAutomationLanes` routes edits through the DOM edit session, targeting the
selected element because that is what the attribute commit path writes to.
Row height reserves each lane at its own height rather than counting it as
another keyframe lane, and `TimelinePropertyLanes` gains a footer slot so the
lanes share the keyframe disclosure — and its `aria-controls`.
`TimelineElement` moves to its own module: playerStore had reached the 600-line
studio ceiling exactly and could not carry another field. It is re-exported from
there, so no importer changes.
🤖 Generated with [Claude Code](https://claude.com/claude-code)
A structural edit — an effect added, removed, bypassed, or a filter's pole
count switched — was dropped. `buildFxChain`'s update reports false when the
change is not merely new values, and the attribute observer ignored that, so
the edit only took hold when the persisting write reloaded the composition.
That reload restarted every playing track, which is what was heard as the
audio chopping.
The graph is now swapped in place: the old effects are detached, the new ones
built and connected between the same source and gain, and any lanes
re-scheduled onto the new nodes. The source node is never touched, so playback
does not restart.
A track with no chain is watched too, rather than wired through and forgotten,
so adding its first effect is heard the same way. That means the function
always returns a disposer instead of null for the empty case.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
The envelope was scheduled onto the transport's gain AudioParam, but the
runtime rewrites that gain every tick from `data-volume` and the GSAP-seeked
value — so it was erased within a frame. Volume automation was correct in the
render and inaudible while previewing.
The lane now feeds the per-tick path where the probed volume keyframes already
sit, checked ahead of them so the two cannot fight, and the transport no
longer schedules volume at all: one mechanism instead of two racing.
The cost is honest — in preview the level steps per tick rather than per
sample, exactly as the existing keyframe path does. The render still bakes it
into the PCM sample-accurately, and FX parameters are still scheduled on their
own AudioParams, since nothing rewrites those.
Parsed lanes are cached by attribute text: the runtime asks once per tick per
track, and parsing there would run the JSON parser 60 times a second for a
value that only changes on an edit.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
The offline render schedules FX lanes with the same scheduler preview uses,
inside the OfflineAudioContext that already runs the same graph builders. The
input WAV is the clip's own audio from its first sample, so clip-local time
is offline time and the envelope needs no offset.
Volume lanes take the existing PCM bake rather than a second mechanism: the
lane is converted to keyframes, so a straight fade stays two of them and only
a bent segment is sampled — the baker interpolates linearly and would
otherwise quietly straighten the curve. A volume lane supersedes keyframes
probed from the timeline, which `lint` already warns about.
A browser test sweeps a lowpass from below a 2 kHz tone to well above it and
measures both ends. Parsing the envelope is not the same as scheduling it,
and only running the real thing tells the two apart.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Schedules each lane onto the AudioParams behind its knob using native ramps
and value curves. Nothing evaluates the envelope per frame: it is handed to
the audio thread once, so it stays sample-accurate however busy the main
thread is, and the offline render will schedule it the same way.
Timing comes from the transport, so an envelope survives seeking into the
middle of a clip, a clip that has not started yet, and a playback rate that
compresses clip seconds into context seconds.
A straight line is only scheduled as a ramp when nothing bends it — no
curvature, a linear parameter scale, and no unit mapping. Log-scaled
parameters and mapped ones are sampled instead, since a delay knob in
milliseconds and a wet/dry pair moving in opposition are not linear in the
parameter they drive.
Lanes with nowhere to write are skipped rather than reported: a one-pole
filter exposes no frequency param, and the worklet effects expose none at
all. Editing an envelope mid-playback re-aims it at the live playhead rather
than restarting the track.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Marks the knobs an automation lane can drive and has each graph builder hand
back the AudioParam behind them, so a scheduler can write to a running effect
without knowing what the effect is.
A knob is not always one AudioParam. A wet/dry mix is two gains moving in
opposition, and a knob in milliseconds drives a delay time in seconds, so
each target carries the mapping out of the knob's own declared unit.
What stays unautomatable is stated where it is decided: a WaveShaper curve, a
convolution impulse and a one-pole filter's coefficients are all rebuilt
wholesale rather than scheduled, and the four worklet effects take values by
postMessage rather than through AudioParams.
The registry flag is written by hand, so a test builds every effect and
checks the exposure both ways — nothing flagged is missing, nothing exposed
is unflagged. A flag that lied would offer a lane that silently did nothing.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Adds the data model behind Ableton-style automation lanes: breakpoint
envelopes over track volume or one knob of one effect in the track's FX
chain, stored on the element as `data-automation`.
Times are clip-local, so an envelope travels with the clip when it moves —
the clip-envelope model rather than arrangement automation.
`sampleAutomationLane` is the single interpolator. The lane drawing, the
preview scheduler and the render bake all call it, so the picture and the
sound cannot disagree about the curve. Log-scaled parameters interpolate in
log space, matching what their own knob already promises.
FX nodes gain a stable `id`, minted by count rather than randomly so the
document is the same on every machine. Lanes address nodes by id, so
reordering a chain never re-points a lane at a different effect, and a lane
whose effect was deleted is dropped rather than left to reattach.
Also warns when a track carries both a volume lane and a GSAP volume tween,
since only the lane is heard and the tween silently does nothing.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Clears the health findings the FX stack left behind: the chain-node render
callback was a 70-line closure over half of FxSection's state, and the two
reorder arrows were the same button written twice.
Also drops two exports with no consumers, and registers the audio FX runtime
stub as an entry point — it is bundled by file path, so nothing imports it.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
An AudioWorkletNode cannot be constructed before its processor is registered —
it throws, and the surrounding chain is lost with it. `attachElementFxChain`
built the chain first and only then called `ensureAudioFxWorklets`, so every
worklet-backed effect (compressor, limiter, gate, bitcrush) threw on
construction and the track fell back to dry. Instrumenting the preview showed
`hf-compressor: InvalidStateError` with addModule never called at all.
When the module has not landed yet the track now plays dry and the graph is
swapped in once registration resolves, so the effect arrives a moment late
instead of never.
Registration is also tracked per context rather than in one module-level
promise. A processor registered on one AudioContext does not exist on another,
so the shared promise made every context after the first believe it was ready
when it was not — the studio's transport owns its own context, which is exactly
that case.
With the worklets actually running, the compressor's per-sample log10 and pow
became real audio-thread work. Samples below the knee have a gain of exactly
unity and need neither, so the envelope is now compared in the linear domain
and the transcendentals only run for samples that are actually being
compressed.
Dragging a knob wrote the chain through the persisting attribute path on every
input event. That path refreshes the preview, which reloads the composition and
reschedules audio — so a single drag reloaded dozens of times and playback
stuttered the whole way.
Drags now go through `onSetAttributeLive`, the same path colour grading uses for
scrubs: it coalesces undo entries and sets `skipRefresh`, so no reload happens.
The persisting write fires once, when the gesture ends — pointer-up or blur for
a slider, Enter or blur for a typed value. A select commits immediately since
there is no drag to wait for.
While dragging, the control is driven from local state. Waiting for the value to
round-trip through the element attribute made the knob lag behind the pointer.
For the change to be audible without a reload, the graph now follows the
attribute: the chain installed by the transport observes the element and
re-parameterises itself in place, so a value change lands on the next
128-sample quantum. A shape change (effect added, bypassed, pole count) cannot
be patched into a running graph, so it still waits for the next schedule rather
than cutting the audio mid-play.
The regression test drags a slider through several values and asserts the
persisting handler is untouched until release.
Splices an element's FX chain into the playback graph so preview stops being
silent about effects, and wires the carve button that was previously inert.
The chain goes between the decoded source and its gain stage: effects see the
raw signal and volume automation rides on their output, matching the order the
offline render uses. Since preview and render call the same graph builders,
what is heard while scrubbing is what gets written.
The splice lives in the transport rather than on the `<audio>` element. The
transport plays each track from a decoded AudioBuffer and mutes the element to
avoid doubling, so capturing the element with createMediaElementSource would
have processed a stream nothing is listening to — it looked like it worked
because the call succeeded, and the audio was unchanged.
A chain that cannot be built plays dry rather than silencing the track, which
is the right failure in preview: the author keeps working and hears the source.
The render still refuses, because shipping the dry signal there would be wrong.
Carve now analyses for real: it decodes the chosen voice track, ranks its bands
and writes the resulting peaking filters onto this track. Generated nodes are
tagged `fromCarve`, so re-running replaces the previous carve instead of
stacking another set on top of hand-added effects.
Known limitation: the graph is built when a source is scheduled, so a knob
turned mid-playback takes effect on the next play or seek rather than
immediately. Live re-parameterisation needs the transport to hold the handle
and forward updates.
Adds `audioFx` to the editing-affordances contract and renders the FX panel in
the inspector when an `<audio>` element is selected.
The section is audio-only. A `<video>` carries its sound on a separate
`<audio>` element, so an FX chain on the video would have nothing to process.
Chain and carve settings are written straight back onto the element as
serialised attributes, the way colour grading carries its config, so
persistence is an ordinary attribute write and needs no new server route. A
chain that cannot be parsed renders as empty rather than breaking the panel,
and the attribute is left untouched until the user changes something.
The collapsed group summarises what is on the track ("2 effects + carve") so
the state is visible without expanding it.
Wired into PropertyPanelFlat rather than PropertyPanel: STUDIO_FLAT_INSPECTOR_ENABLED
defaults to true, so the flat inspector is what actually renders.
Controls for the whole chain: add, remove, reorder, bypass, and every knob each
effect declares.
Nothing in the panel knows what a compressor is. The registry supplies each
parameter's range, step, unit and scale and the panel renders what it finds, so
adding an effect or a knob upstream needs no change here, and the panel cannot
offer a value the renderer would reject — a typed-in figure is clamped into the
declared range on the way through.
Frequency and time controls span three or four decades, so those declare a log
scale and the slider maps exponentially; a linear slider would spend most of
its travel somewhere useless.
Reorder is a first-class control because chain order changes the sound: a
reverb before a compressor is not the same as after.
Carve gets its own block rather than an entry in the add menu, with a picker
for the voice track to listen to. It processes this track based on another one,
which is how a sidechain control works — it lives on the track that changes,
and names the source.
`processCompositionAudio` reports per-track failures in its result, but an FX
failure it cannot degrade past — a browser that will not launch, a chain that
will not build — rejects instead. `runAudioStage` had no try, so that rejection
escaped to the orchestrator as an unclassified pipeline exception, losing the
stage/owner/retryable classification this stage exists to attach, and skipping
its abort check on the way out.
It now lands in `audioError` alongside every other cause, while an abort still
keeps its own shape rather than being reported as an audio problem.
Not done here: committing the generated `audio-fx-runtime-inline.ts` so a fresh
clone typechecks packages/engine without building first. The bundle is built from
the stub, and the stub changes three times across this stack — so the artifact
differs per branch and would conflict on every restack. Its model,
position-edits-render-inline.ts, is committed only because it is stable. Building
before testing is this monorepo's existing contract (studio's tests need core's
dist too), so the gap is not specific to audio FX and is better closed by a build
ordering gate than by committing a per-branch artifact.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
