# PLAN The post-1.0 roadmap. Seventeen queued items consolidated into overlapping areas and sequenced into a Phase → Wave → Track hierarchy that implementation specialists can be dispatched against directly — **plus Phase Γ**, which did not come from those seventeen (it came from a direct interview, 2026-08-01) and is scoped in `docs/product/instrument-control-surface.md`. ## What this doc is, and how it relates to the others - **`docs/PLAN.md`** (this file) — the active on-deck specification list. Each track is written so a specialist brief is writable from this file alone: goal, consolidated source items, surface boundary, behavior, acceptance criteria, open questions, prerequisites. - **`docs/TODO-1.0.md`** — retained as the **verbatim-provenance appendix**. It holds Daniel's raw asks and every answer round, unedited; where this plan compresses a behavior bullet, that file is the backing record. Items are cited here by number (e.g. "consolidates items 1, 8, 14"). It is not a work queue any more; this file is. - **`docs/TODO.md`** — deferred follow-ups with recorded rationale, unrelated to the seventeen (with one flagged intersection: see "Flagged for awareness" below). - **`docs/COMPLETED.md`** / **`docs/ARCHIVE.md`** — doc-keeper's. When a track here finishes, its point is removed from this file and appended to `COMPLETED.md` with any deviation between landed code and spec noted. - **`docs/product/`** — the product-design reasoning behind prior phases. Grep for a cited section rather than reading a file whole. **Worktree slug convention:** `p-w-t-`. Greek phase letters transliterate: **Θ → `th`**, **Ξ → `xi`**, **Γ → `g`**. So Θ-W1-T1 dispatches into `pth-w1-t1-zone-retirement` and Γ-W1-T1 into `pg-w1-t1-knob-interaction-law`. ## Decision state Everything carried forward from `TODO-1.0.md` is classified **[verify]** (answerable by reading code or running the DAW) or **[propose]** (a design call made at implementation review with a proposal, not a Daniel call); that classification is preserved per question, attached to the track that will answer it. Θ-W3-T1's two genuine **[Daniel]** questions — which no amount of code-reading could answer — are both ruled on and the track has landed; see `docs/COMPLETED.md` for the full narrative. **Reload tier = Grouping B** (continuous knobs live: filter cutoff/Q/ morph/drive/mod amount/key-track, every envelope stage time and level; root note, loop span, and start frame still trigger a full reload). **Mid-stage rule = candidate (iv), hold normalized stage position** (φ = elapsed/duration held fixed across a duration change, then advancing at 1/newDuration). **Phase Γ opened six [Daniel]-class forks (Γ-F1…Γ-F6) and all six are ruled** (Daniel, 2026-08-01) — the rulings are folded into the tracks below and indexed in `docs/product/instrument-control-surface.md` §8. **Γ-F6 closed with a correction to the analysis, not merely a ruling**: dynamic reported latency is routine for VST3 instruments and REAPER handles it as a matter of course; what makes the mandated restart expensive *here* is self-inflicted (`setActive(true)` calls `reloadInstrument`), so the cost is ours to reduce and the reduction is filed in `docs/TODO.md` rather than designed around. **Γ-F3 was subsequently REVERSED and a seventh fork opened, both by Daniel's later rulings of 2026-08-01.** Γ-F3 (*"the stage-time ceiling stays 2.0 s"*) is replaced by *"extend the stage lengths to 10s"* — the ceiling moves in Γ-W1-T1. And **Γ-F7 is OPEN**: the VST3 parameter *order* (signal flow, or the editor's visual rows), a forever commitment that cannot be closed by proposal at review. It blocks nothing until **Γ-W4 dispatches**, which is the last track of the last wave of the phase. **Exactly one track in this plan carries an unanswered [Daniel]-class question: Γ-W4-T1, and it is Γ-F7.** ### Flagged for awareness — not blocking, but decision-grade 1. **Item 15 has an unresolved cross-artifact seam, and it is the phase's largest unknown.** The instrument is a read-only bank consumer by invariant (`src/shell/instrument/CLAUDE.md`), and the one previous attempt at an instrument→extension relay (S13) closed with a **DEGRADED** spike verdict and was deferred (`docs/TODO.md`). Resample requires that crossing. Ξ-W2-T1 opens with the architecture decision and this plan names the candidates rather than assuming the deferred relay shape; see that track. Consequence to hold: if every candidate fails verification, item 15's "one click from inside the VST" framing is what gives, not the read-only invariant — the fallback is a bindable extension-side action. 2. **The "Γ before Ξ-W2" ordering is VIOLATED, it was never Daniel's choice, and Γ now owns the correction.** Daniel, 2026-08-01: *"xi was started before I spun you up, we'll have to correct phase xi inside gamma. wasn't a choice."* Ξ-W2-T1 (`resample-bake-chain`) ran ahead of this plan's sequencing claim, so the bake's settled reset scope — which enumerates parameters **by name** — ships incomplete: it cannot name rate, pitch offset or the limiter flag, none of which existed when it was written. **This is no longer a scheduling constraint to honour. It is a correction obligation with a named owner: Γ-W3-T2 `bake-reset-amendment`.** The classification costs no Daniel decision — `docs/product/instrument-control-surface.md` §3.4 pre-classifies all three against Ξ-W2's own ratified rule (all **reset**) — but the amendment must be written **against what Ξ-W2-T1 actually shipped, not against what this plan predicted it would ship.** Ruling 1 adds a second correction of the same shape, homed on Γ-W4-T1 rather than here: see item 3. 3. **The one-way doors are now IN-PHASE, and the sweep for them is a delivered artifact.** Ruling 1 (Daniel, 2026-08-01) schedules VST3 parameter reporting **inside Phase Γ**, as Γ-W4-T1. Everything that participates in a parameter's normalization therefore freezes at the end of this phase rather than at the start of some later one, and anything that ought to move must move first. - **The taper** (Γ-W1-T1) — known, and the reason this phase was ordered as it was. - **The stage-time ceiling 2.0 → 10.0 s** (Γ-W1-T1) — Γ-F3 **reversed** by Daniel's *"extend the stage lengths to 10s."* A range endpoint is normalization exactly as much as the curve between the endpoints is. - **Two further doors that need action, both new**, both landing on Γ-W1-T1: every default must have an **exact normalized preimage** (a host's reset-to-default has no `resetDeckParam` bypass to use), and the filter's four `*Norm` controls **must not be re-tapered** (their laws are already wire-frozen in payload v9). - **Six more constants freeze without needing to change**, and three are already frozen for unrelated reasons; the complete sweep, with dispositions and with what was checked, is `docs/product/parameter-automation.md` §8. **That doc is no longer scoping-only — §§6–10 are the specification Γ-W4-T1 is built from.** ## Phase-wide acceptance criteria These bind every track in all three phases and are stated once here rather than repeated per track. **Phase Γ adds five of its own**, stated in its phase header. ### Structural (root `CLAUDE.md`, Daniel 2026-07-28) - **More directories is a must; more files is good; ~600-line file ceiling.** The ceiling is the *bar*; a responsibility seam is the *method*. Bisection-to-hit-the- number is rejected. `sampler_core.cpp` (956 lines) is the standing documented hot-path exception — Θ-W1-T1 re-seams it, and any surviving over-ceiling TU must carry the same explicit justification. - **Templates where earned** — compile-time dedup with zero runtime cost, off the hot paths. Not for types that differ in name only. - **SOLID is great, but saved CPU is better.** No dispatch-stack blowouts anywhere; prefer static polymorphism where the types are compile-time-known. ### Performance guardrails Root `CLAUDE.md`'s five extension-side guardrails (peaks envelope compute, audition, realtime-capture tick, JSON, `FxBypassGuard`) are unchanged by this plan; no track here touches them. The instrument adds a sixth surface that binds every Θ track: - **`process()` — the per-voice-per-sample path — takes no new indirection.** The filter tick, the envelope evaluation (staged *and* spline), the pitch-shift read, and the loop read all sit on it. Concrete, inlineable types only: **no `IEnvelope`, no `IFilter`, no virtual per-voice `tick()`**. A filter with two modes is a branch-predictable switch or a compile-time-known dispatch, never a vtable. Spline evaluation is a binary search over a point array, not a polymorphic curve object. - **No allocation, no file I/O, no bridge call in `process()`.** The off-audio-thread `reloadInstrument` + atomic pointer swap stays the only way new state reaches the audio thread. Every new parameter this plan adds follows that path. - **A split that would add a hot-path indirection is out of scope — rework it or drop it.** ### Product invariants - **Capture and placement are separate acts.** No track here may place a timeline item. Item 15's bake explicitly must not, and one of its candidate architectures uses a *temporary* arrange mutation — that candidate must leave the arrange byte-identical. - **Prune is the single, exclusive file-deletion authority.** Item 15's "replace" never deletes bytes; item 17's consolidation may not weaken any protection prune has today. - **The instrument never writes the bank.** Item 15 is the first feature that needs to, and it resolves that by *asking the extension*, not by breaching the invariant. - **Migration bar: a project saved before a change reopens sounding identical.** Holds everywhere except item 16's genuinely-multi-zone case, where Daniel deliberately relaxed it. - **Every pure module gets a `_tests` target** that runs without REAPER or a DAW. New pure modules in this plan are not optional-test. --- ## Phase Θ — ReaSampler 9000: one parameter set, a filter, shapeable envelopes, a legible editor **Ships:** the instrument with the zone system retired, a resonant HP/LP filter stage in the voice path, curve-shapeable and spline-drawable envelopes on all three EGs, Gate-mode loop sustain, and a re-laid, high-DPI-clean editor — plus the two extension drag/drop defects that block getting captures into it. **Consolidates items** 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 16. **All seven waves have landed — Phase Θ is complete.** W1 through W7 each carry their own landed note above; see `docs/COMPLETED.md` for every track's full narrative. Θ-W7 was opened after Θ-W6-T1 shipped, to fix two rendering defects Daniel found by eye; it did not exist in the plan when this phase was originally scoped. **The organizing constraint.** Three surfaces in the instrument are single-writer by nature and dictate the wave shape: 1. **The parameter model** (`zone_params.h` + `component_state_io`) — every parameter addition touches both. Two tracks adding parameters concurrently is a merge fight and two competing `ComponentState` version bumps. 2. **The voice render path** (`sampler_core.cpp`) — filter insertion, envelope evaluation, loop read, and the Trigger tail all live there. 3. **The Sample face** (`editor_paint_sample.cpp` 516 lines / `editor_input_sample.cpp` 583 lines) — every UI item repaints it, and both are already at the ceiling. Parallelism in this phase therefore comes from **splitting the Sample face into bands** (done once, in Θ-W1-T1) and from **extension-side work being genuinely disjoint** — not from running two parameter-model tracks at once. Where a wave has one track, the collision is real and the serialization is the correct answer. --- ### Θ-W1 — Collapse and re-seam **All three tracks have landed** — Θ-W1-T1 (`zone-retirement`), Θ-W1-T2 (`capture-handoff-bugs`), and Θ-W1-T3 (`filter-dsp-port`) — see `docs/COMPLETED.md` for the full narrative of each. Between them: the zone subsystem is retired, the wave's two responsibility seams (the `sampler_core` split, the Sample-face band split) are in place, the two extension-side capture-handoff defects are fixed, and the filter DSP has landed as a standalone pure module — Θ-W2-T1 has since wired it into the voice path (see below). --- ### Θ-W2 — Filter in the voice path; waveform and chrome bands **Depends on W1 for:** the one-parameter-set model and the `sampler_core` seam that T1 writes the filter into; the `filter` module T1 wires up; the Sample-face band split and band-stack allocator that T2 and T3 fill; and W1-T1's key-range answer, which decides what T3's piano strip displays. Authoring any of this against the per-zone model means writing storage plumbing W1 deletes. **All three tracks have landed** — Θ-W2-T1 (`filter-voice-path`), Θ-W2-T2 (`stereo-waveform-lanes`), and Θ-W2-T3 (`toolbar-and-piano-strip`) — see `docs/COMPLETED.md` for the full narrative of each. Between them: the filter sits in the per-voice signal path with its own deck, the waveform band shows both channels in stereo mode behind a type-enforced full-height overlay contract, and the chrome band's toolbar and piano strip are cleaned up per spec. The three tracks were disjoint by band — T1 owned the parameter model and the deck band, T2 owned the waveform band, T3 the chrome band — and none re-allocated the band stack. --- ### Θ-W3 — Live parameters, then the staged envelope system **Depends on W2 for:** the filter envelope's existence — items 1, 8, and 14 govern *three* envelopes, and the filter is the third; and for the Filter deck, which must exist before it can receive a corner radio switch and inner curve dials. T1 additionally depends on W2-T1 for the filter itself: the filter is the first control set where the latched-at-note-on delivery model fails audibly, and it is what made the defect visible. **Both tracks have landed** — Θ-W3-T1 (`live-parameter-delivery`) and Θ-W3-T2 (`staged-envelope-curves`) — see `docs/COMPLETED.md` for the full narrative of each. Between them: every continuous playback control (filter cutoff/Q/morph/drive/mod amount/key-track, every stage time and level on all three envelopes) now reaches a sounding voice live instead of latching at note-on, and the envelope-overlay editor grew from an amp-only fixture into the shared graphical surface for all three envelopes — a corner radio switch per deck (none active by default), curve-shapeable segments on every sloped stage (0.1–10 exponent, an inner dial paired with an overlay knot), the release-right-anchored AHDSR layout against the pitch envelope's 1:1 AHD, and the Trigger amp/filter fade pair folded into a Trigger AHD, consolidating what were two staged-shape mechanisms into one. The Trigger × Preserve end-of-sample click is fixed; the landed fix is wider than scoped, also ringing out Gate × Preserve × source-exhaustion, previously a hard cut. The ordering was deliberately serial — T1's live-delivery mechanism landed first so T2's new curve exponents and Trigger AHD fields were authored directly into it rather than backfilled afterward. --- ### Θ-W4 — Loop sustain and the velocity deck **Depends on W3 for:** the envelope system both tracks compose with — T1's loop-sustain is the Gate-mode sustain the AHDSR releases out of, and T2's bipolar pitch/filter curves modulate targets whose envelopes W3 just reshaped. T2 additionally depends on W2-T1 for the filter's existence and on W2-T3 for the preview button's toolbar position. **Both tracks have landed** — Θ-W4-T1 (`gate-loop-sustain`) and Θ-W4-T2 (`velocity-deck-and-bipolar-curves`) — see `docs/COMPLETED.md` for the full narrative of each. Between them: loop points are now a usable feature, with a Gate-mode loop acting as the sustain and a parameterized crossfade at the seam; and the three velocity-curve popups (amp, pitch, filter) now live together in a new VELOCITY deck group, with the pitch and filter curves bipolar and flat-by-default so their modulation is off until drawn, while the amp curve stays unipolar and unchanged, and the preview button's text is replaced by a drawn play-triangle glyph. Params payload reached v11 with T1's loop block and v12 with T2's velocity→pitch curve appended after it. --- ### Θ-W5 — Spline EGs **Depends on W4 for:** the bipolar velocity-curve domain (W4-T2) — the spline algorithm is **singly implemented and multi-referenced**, so its enhancement must land against the final consumer set, and the last consumer to change domain is the pitch/filter velocity curve; and for the Gate-mode loop (W4-T1), since "Gate is unavailable in Spline mode" is only a real, testable rule once Gate has something to be unavailable *for*. It also depends on W3's radio switch, which is how a spline contour reaches the overlay at all. **Θ-W5-T1 has landed** — `spline-egs` — see `docs/COMPLETED.md` for the full narrative. It shipped a free-drawn alternative to every staged envelope: pitch, filter, and amp EGs can switch Staged → Spline and have their contour drawn directly on the waveform overlay. The one shared monotone-spline implementation gained hard points — sharp corners, no smoothing on either adjacent segment — flowing to every consumer including the existing velocity→amp transfer curve, no fork. Both Staged and Spline state persist simultaneously (saved-but-inactive, lossless round-trip); params payload reached v13, and v12 projects still load. Gate is unavailable while a Spline EG is active; the contour is a pure time function over the full sample length, normalized and drawn 1:1 with the sample's time axis. Point grammar converged on left-click add / right-click delete / control-click hard-smooth toggle, one grammar across both spline consumers. Staged segment knobs and their inner curve dials render disabled and reject edits while Spline is active. Point-count ceiling: 128, a musical bound rather than a performance one. A follow-on change in the same track reworked deck cell width: `-1` in `cellIds` now means one cell's width, reserved and redistributed, rather than a blank cell holding geometry — a Trigger face that drops Sustain and Release gets wider cells instead of dead slots; group widths, row packing, deck height, and Gate-mode cell widths are unchanged. --- ### Θ-W6 — Editor legibility pass **Depends on W5 for:** the last change to a drawn surface. Item 13 is an audit whose output is a disposition list over "every class of drawn surface," and item 10's sizing pass is judged by eye over the finished layout — running either while the spline contour, the disabled-knob state, or the deck inventory was still moving would have meant auditing and then re-auditing. Θ-W5-T1 has landed (see `docs/COMPLETED.md`), so that surface has stopped moving and this dependency is satisfied. The source doc names this sequencing as an observation (item 13 after the layout/knob work); this plan adopts it as the boundary. **One track.** Both items repaint essentially every surface in the editor; concurrent tracks would collide everywhere. **Θ-W6-T1 has landed** — `legibility-and-antialiasing` — see `docs/COMPLETED.md` for the full narrative. It shipped both halves together: knobs grew 28→40 px (inner curve dial 14→20), the deck cell 48×58→60×74, and the label band 12→16 px, now drawn in `Font::Label` rather than `Font::Micro` — group captions and toggle segments deliberately stayed `Font::Micro`, since bumping them would outgrow row 1's headroom at the floor width. The editor's default/minimum size grew 840×620→980×680 to fit the wider deck at floor width; an existing saved instance's window grows on open, and the floor is validated by a derived test rather than literals. All fourteen time-constant labels now read in ms (display-only; internal representation untouched) — `holdFraction` knobs, `Len %`, and the bank panel's duration readout stayed out of scope. Double-click resets each ring independently — outer ring resets the value, inner dial resets the exponent to 1.0 — reaching the chrome's preview-velocity knob too via a shared `inKnobFace` rule. The antialiasing audit fixed knob arcs and needle, the inner dial arc and needle, staged and spline envelope slopes, the spline contour, the velocity-popup trace, the waveform outline, and the preview triangle; node handles, curve knots, knob discs, buttons, piano keys, loop markers, borders, gradients, and text were already clean. The disposition table is a standing artifact in `docs/product/visual-design-language.md` §8. The piano-key open question is answered: not aliasing — every key is an axis-aligned `LICE_FillRect`, so the earlier width defect was integer-division residue in the tiling, not a sloped edge. High-DPI host scaling itself is unverified (deferred, see `docs/TODO.md`). All visual outcomes remain pending Daniel's by-eye sign-off on `dev`. --- ### Θ-W7 — Arc-and-spline antialiasing fix **Depends on W6 for:** a drawn surface to find a defect on — this wave did not exist in the plan; it was opened after Daniel found two rendering defects by eye once Θ-W6-T1 shipped, so the audit's own output is what surfaced them. **One track.** **Θ-W7-T1 has landed** — `arc-and-spline-aa` — see `docs/COMPLETED.md` for the full narrative. The stacked-`LICE_Arc` knob and dial rings never reached an opaque core (peak alpha measured 138/255), and the staged/spline envelope and velocity-curve traces were fully aliased rather than gapped, from integer `cy` quantizing the slope. Both defects, plus the two needles, now route through one pure analytic thick-stroke rasterizer — coverage in a new `core/ui/stroke_aa`, the single LICE blend in a new `shell/instrument/editor_stroke` — replacing `LICE_Arc` and `LICE_ThickFLine` outright. Measured: arc peak alpha 138/255 → 255/255, arc perpendicular-weight ripple 67% → 5%, spline weight ripple 29% → 3%, at a cost of +0.09 ms per full editor repaint. Daniel then ruled every sub-2 px stroker width up to 2 px, since the stroker only guarantees an opaque core at width ≥ 2 px; the knob track arc, the inner-dial needle, and the deck's mini velocity trace each moved 1.0 → 2.0 px. `docs/product/visual-design-language.md` §8 is corrected — a false "keeps every ring antialiased" claim is deleted, the rows are re-dispositioned with measurements, and the audit's methodological lesson (verifying which primitive was called is not verifying what it rasterized) is recorded as a standing blockquote. All visual outcomes remain pending Daniel's by-eye sign-off on `dev`. --- ## Phase Ξ — The resample loop **Ships:** one consolidated, fully robust provenance/usage tracking system, and on top of it the one-click in-sampler resample — dial → bake → dial again, with the bank as the medium each iteration passes through. **Consolidates items 15, 17.** **Why these two and not more.** Item 17 is a **prerequisite of meaning** for item 15's bank-side half: the replace-vs-add rule is "does provenance-tied usage exist," which denotes nothing until the consolidated lineage records exist. Item 17 is otherwise independent of the editor chain — which is what makes Ξ-W1 concurrency-safe with Θ. **Ξ-W2 onward requires Phase Θ complete.** Item 15 presupposes the processing surface it bakes — "filtering, pitching, amp all set up nice" is the instrument items 1, 2, 3, and 14 build — and its settled reset scope enumerates the filter parameters, the spline contours, and the loop points by name. Baking a processing chain that does not exist yet is not a schedule preference; the feature is not expressible. Phase Θ landed as of Θ-W7-T1 (see `docs/COMPLETED.md`); this gate is satisfied. --- ### Ξ-W1 — Consolidated tracking, and the programmed-note model #### Ξ-W1-T1 — `tracking-consolidation` **Landed** — see `docs/COMPLETED.md` for the full narrative. The provenance/usage territory is now one system: a new `src/core/tracking/` directory holds `origin_ledger` (the record family — `OriginRecord`/`OriginKind`, the insertion-ordered `OriginLedger`, its JSON codec, and the `Fresh`/`Loaded`/`Unreadable`/`FutureVersion` load classification) and `tracking_authority` (the one decision surface: `pruneProtection` and `tiedUsageExists`), retiring `core/model/owned_manifest`. Both prune's protected set and the resample's replace-vs-add decision are computed from one borrowed `TrackingState`, so the two safety-critical consumers cannot drift apart. `sample_usage` deliberately **stays in `core/wire`** — the consolidation is of the decisions, not the codecs. The deferred persisted-instance-identity fix was **not** folded in — the deferral is restated in `docs/TODO.md`, its one home. This track landed `OriginRecord`'s birth-time `parentSampleId` chain as the lineage mechanism, but **Ξ-W2-T1's "naming and lineage" open question (jointly held with this track) is unaffected and still theirs to close** — display naming and user-readable iteration lineage were not decided here. #### Ξ-W1-T2 — `note-program-model` **Landed** — see `docs/COMPLETED.md` for the full narrative. The programmed-capture- signal model is a new pure module directory, `src/core/instrument/note/` — a fourth peer of `engine/`/`map/`/`ui/` under `core/instrument/` — holding `musical_division`, `tempo`, and `note_program` (`Velocity`, the denominated `OffsetAmount`, the anchored `StartOffset`/`EndOffset`, `NoteProgram`, `resolveNote`). **Both open questions below are answered, for Ξ-W3-T1:** negative offsets are legal in both directions (sign uniform, positive is later in time; only an inverted window is refused, reported via `ResolvedNote::windowCollapsed`), and the denomination seam is confirmed — note length stays musical-division-only, and an offset stores the denomination it was entered in. --- ### Ξ-W2 — The bake chain **Depends on Ξ-W1 for:** the consolidated lineage records that make replace-vs-add computable (T1) and the programmed-note record the offline pass renders (T2). **Also depends on all of Phase Θ** — see the phase note above. **This wave ran AHEAD of Phase Γ, and that was not a choice.** The plan asserted Γ must land first so the bake's reset list would be complete on the day it shipped; Ξ-W2-T1 was already live. The consequence is owned, not absorbed: **Γ-W3-T2 `bake-reset-amendment`** completes the list afterwards, and **Γ-W4-T1** adds the host-notification obligation once parameters exist. Neither is this wave's work, and neither is a defect report against it. **One track.** The bake is one gesture and one chain; the architecture decision at its head governs every step after it. #### Ξ-W2-T1 — `resample-bake-chain` **Goal.** One click bakes the dialed sound into a bank capture, re-points the instance at it, and hands the instrument back at neutral — the dial → bake → dial-again loop, run without leaving the sampler. **Consolidates item 15 (the chain; the popup UI is Ξ-W3-T1).** **Surface boundary — owns:** whichever seam the architecture decision selects (see below), plus `shell/capture/capture_orchestrator` (a resample entry point alongside `captureAndIndexOne`), `core/model/bank_model` + `owned_manifest` at the add boundary, `shell/actions` (a new action, if the decision needs one), and the instrument-side bake trigger. **Does not own** the capture-signal popup's UI — that is Ξ-W3-T1. ##### The architecture decision — this track's first deliverable, before any chain work Item 15 requires a click **inside the VST3 editor** to cause a **bank write**, and the instrument is a read-only bank consumer by invariant. The one prior attempt at this crossing (S13) closed **DEGRADED** and was deferred. Resolve this before building the chain. Two orthogonal choices: **Decision 1 — how the click crosses to the extension.** - **(1a) Ext-state request key + extension-side timer poller**, with a claim/clear nonce — the shape S13 spiked and deferred. It needs a new instrument WRITE seam into ext-state, though the `rsusage_`-prefixed guarded write already establishes the precedent that such a seam can exist without weakening the read-only-*bank* invariant. Known cost: the cross-process handshake race the S17 spec rejected. - **(1b) Direct action invocation over the VST-host bridge — the lead candidate.** A REAPER-hosted VST3 already resolves REAPER API functions **by name** over the host callback (that is how the instrument reads `GetProjExtState`), and can fetch its own host context — the track/take/project it was instantiated in. If `NamedCommandLookup` and `Main_OnCommand` resolve the same way, the editor can invoke the extension's bake action **synchronously**, with no request key, no poller, and no nonce — which dissolves the S13 problem for this case rather than re-litigating it. **[verify]** against `vendor/reaper-sdk/sdk/` (`reaper_plugin.h`, `video_processor.h`, `reaper_plugin_functions.h`) that both resolve over the callback, and that calling them from the editor's UI thread is safe. This is a verification task, not an assertion — do not build on it until confirmed. - **(1c) No crossing — a bindable extension-side action only.** Fallback. It abandons Daniel's "from directly inside the ReaSampler 9000" framing, so it is the answer only if (1a) and (1b) both fail. If it is taken, say so explicitly rather than quietly shipping a panel button. **Decision 2 — what actually renders the audio.** - **(2a) Headless voice-engine render, extension-side.** The extension reads the instance's component state, reconstructs the engine from the shared pure core, renders the programmed note, and banks the result through the normal capture add-path. Exact and fully deterministic. **Trade-off:** the extension currently links `component_state_io` but deliberately **not** `sampler_core`/`pitch_shift` — `component_state_io` was split out precisely to avoid pulling the voice engine into the extension. This reverses that. - **(2b) REAPER offline render of the hosting track**, with the programmed note. Reuses `OfflineRenderBackend` and with it the whole precision-invariant apparatus — exact bounds, bit-identical repeats, relative paths, tail control — for free. **Trade-offs:** it needs a *temporary* arrange mutation to program the note (the realtime backend's temp-track-created-and-removed-cleanly is the precedent), and the existing scope model has no "this one FX only" scope, so post-instrument track FX would be baked in unless a new bypass scope is added. The arrange must be byte-identical afterward. - **(2c) The instrument renders, the extension banks it.** The instrument produces the audio (it already owns the engine) into a temp file or shared buffer; the extension moves it into the bank and indexes it. Splits the work along the existing ownership line — but adds a handoff artifact and its cleanup. **Recommended sequence for the decision:** verify (1b) first — if it holds, the crossing is nearly free. Then pick between (2a) and (2b) on the strength of the "only-the-instrument, not the track chain" requirement: Daniel's ask says "send a trigger or gate **through the sampler** offline," which favours (2a) or (2c) unless (2b) gains a single-FX bypass scope. Record the verdict in this track's review, and if the verdict is DEGRADED, escalate rather than improvise — the fallback is (1c) + (2a). **Behavior — the chain.** - **One gesture, whole chain.** A single click performs: offline pass → capture → bank update (replace or add-distinct) → instance re-point → parameter reset. **One action from the user's side, not a wizard.** - **Offline pass through the instrument's own processing.** The audio is produced by sending a trigger or gate through the sampler **offline** — the instrument's own voice path, with filtering, pitching, and amp exactly as dialed. The recapture is of that processed output, not of the raw source. - **The recapture is a bank capture like any other** — project-relative, indexed, browsable from any surface that browses the bank, recorded in the owned-file manifest, and governed by the same safety rules as every file the system creates. - **The note is the capture's root.** The rendered note is the capture's root note — which is exactly why **the root-note parameter is not reset by resampling**: capturing at root is what makes root survivable, and resetting it would detune every subsequent iteration. - **Gate's hold and tail come from the programmed window.** The programmed note length is the Gate hold bound — the gate holds for the note length, then releases; a Gate loop cycles within the held span and the render still terminates. The **end offset** is the home of the tail policy: captured time past the note's end is where the release rings. - **Replace, or add distinct.** When nothing else references the source capture, the recapture **replaces** it as the bank entry; when other references exist, the original entry stays and the recapture is **added as a new distinct capture**. "Other reference" means **any usage of the source capture tied to it by the provenance/recapture system** — Ξ-W1-T1's records. Read plainly: the reference universe is the resample system's own lineage records, **not** the prune-protection universe. Bank multi-membership, items placed in the arrange, and a plain hold by another instance outside any recapture lineage do **not** force add-distinct, and need not for safety — the superseded file survives until prune, and prune's protection universe is unchanged and broader. - **Replacement never destroys audio bytes.** "Replace" means the bank entry now denotes the recapture; the superseded file is not deleted. Prune remains the system's only file-deletion authority — resample writes a new file and retires the old one to reclaimable-by-prune status; it never overwrites or deletes it. Until a prune reclaims it, the pre-bake audio survives on disk — **the iterate loop's built-in recovery floor.** - **The instance re-points** at the new/corrected bank capture and plays the baked sound. - **Parameters reinitialize to default** — destructive to the dialed settings **by design**: the processing now lives in the recaptured audio, and neutral controls are the starting point for the next iteration. - **Reset scope: only what the bake baked in.** Ratified by Daniel, not derived: - **Reset** (their effect is in the audio): the envelope contours — staged and spline alike — the filter parameters, master gain, the pitch envelope/engine settings, the velocity transfer curves (their effect at the programmed velocity is in the audio), and the loop points (they shaped the render, and old positions are meaningless against new audio). - **Survive** (mapping facts, not present in the audio): the **root note**, whatever remains of key mapping (key-tracking; any key-range concept Θ-W1-T1 settled), and the VOICE group (polyphony behavior leaves no trace in a single rendered note). - **No timeline item, ever.** Resampling is a capture act: it writes a file to the bank and updates the index; nothing is placed in the arrange view. Any framing that auto-inserts the recapture is invalid — and if architecture (2b) is chosen, its temporary programming item must leave the arrange byte-identical. - **Undo/recovery: a plus, not a requirement.** Welcome if it falls out cheaply; the feature ships without it. The guaranteed recovery path is the superseded file surviving on disk until a prune reclaims it. **Acceptance criteria.** - On a dialed-in instrument, one click yields all of: a recapture in the bank, the instance holding that recapture, and the baked-in audio parameters at their defaults — with the root note and the other surviving mapping parameters untouched. - **The bake is audible and faithful:** after the click, playing the programmed capture note (root, at the programmed length, offsets, and velocity, in the active mode) through the now-neutral controls sounds as the dialed instrument sounded just before the click — the processing has moved from the controls into the audio. - **A Gate-mode bake terminates on its own:** the gate holds for the programmed note length, then releases — even with loop-sustain active, the render ends. No indefinite capture. - **After the bake the root note is unchanged** — iteration never detunes; the next bake plays the same root. - **Sole-reference case:** the bank afterwards shows the recapture where the source capture's entry was; no other bank entry is disturbed. **Other-references case** (provenance-tied usage of the original exists, computed by Ξ-W1-T1): the original entry is untouched, a distinct new entry appears, and **every other holder of the original sounds exactly as before.** - **The click deletes no file:** the superseded audio file still exists on disk afterwards, and only a later prune — under the settled orphan rules, only when nothing references it — can reclaim it. - **The arrange timeline is untouched:** no item appears anywhere, on any track, and if a temporary programming item was used it is gone and the arrange is byte-identical. - **Iteration composes:** dial → click → dial → click bakes the second pass onto the first's result, repeatable indefinitely. - **Save/reload:** an instance holding a recapture reloads and plays it exactly like any other loaded capture. - The bake adds nothing to `process()` — the offline pass runs off the audio thread. **Open questions.** - **The architecture decision [propose, with a verification step].** See above. The (1b) bridge verification is **[verify]**; the choice among the candidates is **[propose]**. - **Extension presence [propose].** The instrument plays self-contained with the extension absent, but the bank is the extension's surface and resampling mutates the bank. The natural answer is that resample **requires the extension present and is cleanly unavailable — not silently lossy — without it**; propose the exact behavior at review. - **Reset-scope edge cases [verify].** The rule is settled and the per-parameter classification is ratified. Only a genuinely new parameter — one arriving with a Θ track and absent from the ratified lists — is classified **against the rule** and surfaced at review. Not a new Daniel call. (Θ adds: curve exponents → reset; spline contours → reset, already named; the filter's velocity/key-tracking mod → reset with the filter; loop crossfade → reset with the loop points; the Staged/Spline mode flag → classify.) **Phase Γ's additions are NOT this track's** — this track ran ahead of Γ, so the values Γ introduces (rate, pitch offset, the limiter flag, the loop enable) are amended in by **Γ-W3-T2 `bake-reset-amendment`** afterwards, against what this track actually shipped. Γ-W4-T1 then adds the host-notification obligation over the completed list. Nothing here needs to anticipate either. - **Naming and lineage [propose, jointly with Ξ-W1-T1's lineage-record question].** When add-distinct fires, the new capture needs a display name (derived from the original?), and the bank some way to read iteration lineage across repeated bakes. One proposal, both tracks. - **Provenance of the recapture — homed in item 17**, i.e. Ξ-W1-T1. A resample's recipe is the instrument's own settings, not a track's chain. Nothing to decide here beyond consuming that answer. --- ### Ξ-W3 — The capture-signal popup **Depends on Ξ-W2 for:** the bake chain that the popup programs and its preview must not diverge from. The acceptance criterion "preview and bake cannot diverge" requires one render path, which W2 owns — building the preview against a second path is exactly the defect the criterion exists to catch. **One track.** #### Ξ-W3-T1 — `capture-signal-popup` **Goal.** Let the user program the capture signal — note length, offsets, velocity — and hear it before committing the bake. **Consolidates item 15 (the popup sub-feature).** **Surface boundary — owns:** `core/instrument/ui/curve_popup`'s sibling — a new pure popup geometry module for the capture-signal sheet (mirror the `curve_popup` precedent: centered sheet, width/height clamps, title row, Close button rect, outside-sheet dismissal test) — plus the editor's popup paint/input wiring in the deck or chrome band, and the preview trigger's call into W2's render path. Reads Ξ-W1-T2's note-program record; does not re-own it. **Behavior.** - **A popup menu programs the capture signal:** **note length**, **start and end offsets — in ms AND in beats** — and **velocity**. - **A preview trigger button** auditions the capture note exactly as currently programmed — the user hears the bake before committing it — and the offline pass renders that same programmed performance. - **Note length is a musical-division picker** spanning 1/64th to 64/1 with dotted and triplet multipliers. - **Offsets are anchored** — start to note-on, end to note-off — and each is readable and editable in **both** ms and beats, the two views of one stored value. - **Beat-denominated values resolve against the project tempo under the cursor.** The shell reads the tempo; the arithmetic is Ξ-W1-T2's. - **The programmed velocity is the render velocity** — material because the velocity transfer curves modulate amp, pitch, and filter at that velocity. - House-consistent: drawn through the shared kit by palette role, geometry pure and CTest-covered, no decorative animation. **Acceptance criteria.** - The popup exposes: note length as a musical-division picker spanning **1/64th to 64/1 with dotted and triplet multipliers**; start and end offsets, **each readable and editable in both ms and beats**, anchored to note-on and note-off respectively; and velocity. - **Its preview trigger auditions the capture note exactly as programmed, and the bake renders that same programmed performance — preview and bake cannot diverge.** Verify structurally (one render path), not just by ear. - **Beat-denominated values resolve against the project tempo under the cursor:** the same programmed division yields a correspondingly different rendered duration when the tempo at the cursor differs. - The programmed signal persists with the instance and round-trips save/reload. - The popup's geometry and dismissal test are pure and unit-tested; no hit-test math lands in shell code. **Open questions.** Both of Ξ-W1-T2's residuals (negative offsets; the note-length denomination seam) surface here as UI consequences — if T2 answered them, this track implements the answer; if T2 deferred either, this track is where it becomes visible and must be closed. --- ## Phase Γ — The instrument's control surface **Ships:** the deck reflowed into two categorical rows with a double-height MASTER bus deck, a PITCH/RATE deck with playback-rate and baseline-pitch controls, a master limiter with dynamic reported latency and a real output meter, one consistent knob interaction/taper law across every variable control **over a stage-time range raised 2 s → 10 s**, a fix for staged contour traces drawing straight, a re-approached loop/crossfade marker UX under an explicit chrome-row loop enable, **the Phase Ξ bake's reset list corrected**, and — as the phase's last track — **the instrument's first VST3 automatable parameters, reported to the host under a frozen id contract.** **Consolidates:** none of the seventeen. Phase Γ came from a direct interview with Daniel (2026-08-01); the product reasoning, the measured layout table, the invariant collisions and the fork rulings are in **`docs/product/instrument-control-surface.md`**, and the parameter system's is in **`docs/product/parameter-automation.md` §§6–10**. Read §1.2 (the layout table) and §7 (collisions) before dispatching any track here — every number in this phase is derived there, and `docs/TODO.md`'s old deck-rework geometry is superseded. **Fork state — six ruled, ONE OF THEM LATER REVERSED, and one open.** Indexed at spec §8, folded into the tracks below: - **Γ-F1** — `kEditorMinHeight` stays **680**. - **Γ-F2** — the limiter has **lookahead with DYNAMIC reported latency** (zero when off, the lookahead when on, reported to host PDC). *This inverted the product recommendation;* W1-T2's scope grows accordingly — spec §3.1.1. - **Γ-F3 — RULED, THEN REVERSED THE SAME DAY.** First ruled *"the ceiling stays 2.0 s in this phase"*; then Daniel: ***"extend the stage lengths to 10s."*** `kEnvTimeMaxSeconds` / `kGateStageMaxSeconds` move **2.0 → 10.0 in Γ-W1-T1**, and the `docs/TODO.md` entry that carried the ambition is discharged rather than deferred. **The reversal's cause is Ruling 1** — parameters now ship in-phase, so the ceiling is a one-way door that must be walked through before them, not after. Spec §4.3.1. - **Γ-F4** — there **is** an explicit loop enable, and it lives on the **chrome row**, not in a deck. W2-T2's scope grows accordingly — spec §6.4. - **Γ-F5** — MASTER's reserved slot is **one** cell. The 90 px headroom argument behind that is spec §1.6 and governs every future control addition. - **Γ-F6** — **ship dynamic latency as ruled.** The `restartComponent(kLatencyChanged)` deactivate/reactivate the SDK mandates is accepted: *"the limiter will either be on or off on its instance, toggling during playback is not a use case."* No constant-latency fallback, no measurement gate. *This ruling also corrected the analysis* — spec §3.1.1. - **Γ-F7 — OPEN, and it is the only unanswered [Daniel] question in this plan.** The VST3 parameter **order**: signal-flow order (the deck's own documented rule, layout-independent) or the editor's visual row order after the reflow. Same membership, different sequence, frozen forever the day parameters ship. **Recommendation: signal flow**, because the visual layout has already moved twice and this phase moves it again. Reasoning and both arguments: `docs/product/parameter-automation.md` §6.4. **Blocks nothing until Γ-W4 dispatches**; it cannot be closed by proposal at review. **Ruling 1 (Daniel, 2026-08-01) — VST3 parameter reporting ships in this phase.** Verbatim intent: *"correct the phase gamma plan to account for complying with the VST3 standard for parameter reporting… by the end of gamma we have the automatable params reported. Make the parameter order logical."* `docs/product/parameter-automation.md` was written as scoping and has been **promoted in place**: §§1–5 are the original analysis, **§§6–10 are the specification** Γ-W4-T1 is built from. Three things it decides that the scoping pass left open: the blob stays authoritative and parameters are a third surface onto the one model (§6.1); the id space is an independent, hand-assigned, FOREVER-FROZEN table (§6.2, §6.3); and the exposed list is **derived from the three-state commit predicate**, never hand-maintained (§7). Today the plugin has **zero** parameters — `ReaSamplerProcessor::initialize` (`reasampler_processor.cpp:56-73`) never populates `SingleComponentEffect::parameters`, so `getParameterCount()` returns the SDK default 0. **What the Γ-F6 ruling changed in the analysis, not just in the plan.** Dynamic latency reporting is **routine** for VST3 instruments and REAPER handles it as a matter of course; the SDK's deactivate/reactivate requirement (`pluginterfaces/vst/ivsteditcontroller.h:105-108`) is the normal contract, not an exotic one. What makes the cycle expensive **here** is entirely our own doing: `ReaSamplerProcessor::setActive(true)` calls `reloadInstrument()` — a bridge read plus a full WAV re-decode (`reasampler_processor.cpp:89-97`) — where a typical plugin's `setActive` only allocates and frees buffers, and the deactivate side's freeing of `live_`/`draining_`/graveyard (`:98-107`) is likewise our own design. **The cost is therefore ours to reduce if it ever matters, and the reduction is decoupling reload from activation — not abandoning dynamic latency.** That improvement is filed as a `docs/TODO.md` entry with its trigger condition; it is not scheduled in this phase. **Sequencing against Phase Ξ — the ordering claim is RETIRED and replaced by an owned correction.** This plan previously asserted that Γ must run before Ξ-W2 and called it *"a correctness point, not a preference."* **Ξ-W2-T1 ran first.** That was not a decision anyone took — the track was live before this phase existed (Daniel: *"xi was started before I spun you up, we'll have to correct phase xi inside gamma. wasn't a choice."*). So: 1. **The bake's reset list is incomplete as shipped, and Γ-W3-T2 amends it.** Rate, pitch offset and the limiter flag are all **reset** under Ξ-W2's own ratified rule (spec §3.4), so no Daniel decision is owed — only the edit, and it must be made **against what Ξ-W2-T1 actually shipped rather than against what this plan predicted it would ship.** 2. **Ruling 1 adds a second correction of the same shape, and it lands one wave later.** Exposing the reset-class values as VST3 parameters means the bake's reset must notify the host, and a host automation lane on a reset-class parameter re-imposes its curve onto already-baked audio. Both are Γ-W4-T1's acceptance criteria — that track creates the condition, so it carries it (`docs/product/parameter-automation.md` §9). 3. **The payload-ladder half of the old claim needs re-checking, not restating** — see the ladder block below, which now states rungs **relatively** rather than by number. **The organizing constraint.** Six surfaces are single-writer and dictate the wave shape: `ui/deck_values.cpp` **and the taper module extracted from it** (the taper law and the new ceiling, then the two new controls, then the host normalization — three tracks, three waves), `editor_paint_waveform.cpp` (the contour trace, then the loop marks), `ui/deck_groups.cpp` (the row predicate, then the PITCH/RATE descriptor, then the reflow's row consumption — three tracks, three waves), `engine/voice.cpp` (the Preserve read path, then the rate compounding into it), `shell/instrument/reasampler_processor` (the limiter chain and latency, then the parameter surface), and the params-payload ladder. **Every wave boundary below is one of those collisions**, not a preference. Where a wave has more than one track, the tracks are disjoint by surface. **Resequenced 2026-08-01 (Daniel), three changes.** The prior four-wave shape put the reflow at W3 and the Preserve stretcher at W4; both moved. **Ruling 1 then added a fourth wave** — see "The wave shape after Ruling 1" below. 1. **The reflow is split, canvas from arrangement.** The window floor and the width budget it is derived from land **early** (Γ-W1-T4), so every other UI track in the phase is drawn, tested and judged at the final 1190 × 680 window instead of at a size a later wave changes under it. The two-row *arrangement* stays late (Γ-W3-T1), because it can only be measured once the final PITCH/RATE and MASTER descriptors exist. The seam is stated at Γ-W1-T4. 2. **`preserve-time-stretch` moved W4 → W1-T5.** It is the longest pole in the phase and has **zero dependency on any UI work** — a pure `core/instrument/engine/` module. Scheduling it last was a scheduling error. Consequence: it is no longer Rate's *successor* but its **prerequisite**, which retires the interim resample-and-cancel stand-in entirely — see Γ-W2-T1. Net: four waves become three, and both of the phase's DSP unknowns (the limiter, the stretcher) are exposed in wave 1 rather than one of them landing last. **The wave shape after Ruling 1 — three waves become four.** The parameter system cannot be a track inside any existing wave, and the reason is a chain of hard prerequisites, not caution: - **after W1-T1**, because the taper and the 10 s ceiling *are* the host-facing normalization, and Γ-W1-T1 is also what extracts them into the one module the host will read through; - **after W1-T2 and W2-T1**, because every control that could be a parameter must exist before the list is declared — the list is derived from the control inventory, and an inventory that is still growing produces a list that has to be re-frozen; - **after W2-T1 specifically**, because `isLiveDeckParam` becoming three-valued is the *prerequisite* of the classification, not an incidental of it: the exposed set is exactly `Live ∪ NoteOnLatched`; - **after W3-T1**, because MASTER's inventory (the limiter toggle, the GR bubble, the reserved cell) is the last change to what controls exist at all; - **after W3-T2**, so the bake's reset list is already complete when Γ-W4-T1 adds the host-notification obligation over it — one amendment instead of an amendment to an amendment. The result is a single-track **Γ-W4**, which is the right shape for it anyway: the storage decision governs every part of the work, exactly as Ξ-W2-T1's crossing decision governs its chain. **And it satisfies Daniel's own framing literally** — *"by the end of gamma we have the automatable params reported."* **The params-payload ladder — re-checked, and now stated RELATIVELY.** The old block named v14 and v15 as absolutes. **That is no longer safe to assume**, because Ξ ran ahead of its sequencing and this plan is not the record of what Ξ-W2-T1 actually took. On `dev` today `kParamsPayloadVersion` is **13** (`map/component_state_io.h:154`) and Ξ-W2-T1 was specced to take no rung — but the plan's prediction is not evidence. So: > **Γ owns the next three rungs above whatever `dev` carries when Γ-W1-T2 dispatches, and > that number is READ, not assumed.** In order: **the first rung to W1-T2** (the limiter > enable flag), **the second to W2-T1** (rate + pitch offset), **the third RESERVED for > W4-T1** — spent only if the storage-architecture verification forces a persisted field, > which the specification says it will not (`docs/product/parameter-automation.md` §6.1, > §10). If unspent, that rung falls through to the next phase unclaimed. > > **On `dev` as of 2026-08-01 that resolves to v14 / v15 / v16-reserved.** If Ξ-W2-T1 landed > a bump, every number shifts by one and **nothing else about the ownership changes** — which > is the whole point of stating it relatively. **Every other track in the phase owns no rung**: W1-T1 changes no persisted field (the payload stores raw engine doubles, so both the taper and the new ceiling are persistence-neutral), W1-T3, W1-T4 and W1-T5 add no field, W2-T2's loop enable maps onto the already-persisted `SampleLoop::hasLoop`, W3-T1 is layout only, and W3-T2 changes a reset list, not a format. **The editor's deck is knowingly mis-composed between Γ-W1-T4 and Γ-W3-T1, and that is not a defect report.** Raising the floor without the reflow leaves the greedy whole-group wrap packing two ragged left-aligned rows with categorically wrong membership. Γ-W1-T4 states the exact interim layout; do not "fix" it in a track that does not own it. **Phase-wide acceptance criteria** (in addition to the ones stated at the top of this file): - **Bypassed means byte-identical.** With the limiter off, the per-sample output path is byte-identical to today's bare ramped multiply — the same discipline that makes `live == nullptr` byte-identical to the pre-live core and the filter's exact skip at `modAmount == 0` hold the at-rest path unchanged. - **No `ComponentState` sound change.** A project saved before this phase reopens sounding identical: absent rate lifts to 100 %, absent pitch offset to 0 st, absent limiter flag to bypassed. Re-tapering a knob **and raising the stage-time ceiling** (both Γ-W1-T1) change needle angles only — the payload stores raw engine doubles, so saved values reload bit-identical, and a 3 s stage saved at the old ceiling is simply unreachable-by-hand rather than altered. - **`kVelocityPitchRangeSemitones` / `kPitchDepthMaxSemis` (24.0) does not move.** It is load-bearing in the v12 wire format. The new Pitch knob **reads** it; it does not mint a second ±24 constant. **From Γ-W4-T1 it is also a frozen host normalization** — one more reason, not a new rule. - **The taper has exactly ONE home and three consumers.** Γ-W1-T1 extracts it into a pure module; the knob's needle (`deck_values`), the AHDSR overlay's schematic axis (`envelope_overlay` + `envelope_edit`), and the host's `normalizedParamToPlain` (Γ-W4-T1) all call the same function. **Three functions that agree today is a defect, not an implementation choice** — the failure it prevents is a host automation lane that means one value and a needle that draws another. - **Every default value has an EXACT normalized preimage under its own taper.** Binds Γ-W1-T1 (which designs the taper) and Γ-W4-T1 (which declares `ParameterInfo::defaultNormalizedValue`). `resetDeckParam` bypasses the taper; **a host's reset-to-default cannot**, so exactness in the map itself is the only thing that makes the editor's reset and the host's reset land on the same value. - **Nothing in this phase may re-map the filter's four normalized controls.** Cutoff, Q, morph and drive persist as `*Norm` doubles in payload v9 — their laws are already wire-frozen, and re-tapering them would re-tune every saved project independently of automation. The snap-unit table names them; that is display, not law. - **From Γ-W4-T1, the parameter-id table is FOREVER-FROZEN**, on the same footing as the extension's `"STABLE_FOREVER_STRING"` command ids, the two VST3 class UIDs, and the params-payload field order. No id is reassigned, reused or re-pointed; no exposed parameter's normalization ever changes; a retired control's id is retired with it. Full wording: `docs/product/parameter-automation.md` §6.3. - **The exposed parameter set is DERIVED, never hand-maintained.** A control is a parameter if and only if its commit class is `Live` or `NoteOnLatched`. There is no second table beside `isLiveDeckParam` / `liveCommitFor`, and no list that can drift from it. - **The window floor is 1190 × 680 and must not exceed 1280 × 720.** **Γ-W1-T4 sets it, in wave 1; no other track in the phase may move it**, and from that point every track is authored and judged at it. A track that pushes the floor past 1280 has failed, not overrun. **`kEditorMinHeight` stays 680** (Γ-F1). The remaining **90 px of width headroom is the budget for the life of this layout** — one deck cell is 60 px, so there is room for exactly one more, once. Spec §1.6 states the ledger; read it before adding any control. Chrome-row additions are a **separate purse** (they are paid for out of the title slot, not the floor) and must not be charged against this one. - **Reported latency is zero unless the limiter is on.** `getLatencySamples()` returns 0 with the limiter bypassed, in every track and at every point in the phase. Only W1-T2 may introduce a non-zero value, and only under the limiter-on condition. - **Geometry stays pure.** Every new layout, cap, label and hit-test rule lands in a pure CTest-covered module (`knob_deck`, `sample_bands`, `waveform_view`), never in a painter. --- ### Γ-W1 — Foundations **Depends on:** nothing in this phase. **Five tracks, disjoint by surface** — re-verified against this membership rather than carried over from the four-wave shape: | Track | Owns | |---|---| | **T1** `knob-interaction-law` | a **new pure taper module** under `core/instrument/ui/`, `ui/deck_values`, `ui/envelope_overlay` + `ui/envelope_edit` (the AHDSR schematic axis and its drag inverse), `ui/param_slider`, the three `shell/instrument/editor_input_*` drag paths, `editor_controls.cpp`'s `envClampBounds` only, the shared modifier helper in `editor_internal.h` | | **T2** `master-bus-audio` | new pure `engine/limiter` + `engine/meter_ballistics`, `shell/instrument/reasampler_processor` + `processor_state`, `map/component_state_io` + `params_payload` (**the wave's payload rung**) | | **T3** `contour-trace-curves` | `shell/instrument/editor_paint_waveform.cpp`'s staged trace + a **new pure** tessellation module | | **T4** `editor-floor-and-row-law` | `ui/sample_bands.h` (the floor), `ui/knob_deck.h` (budget constants + two invalidated header notes), `ui/deck_groups` (the row predicate **only**), five test fixtures | | **T5** `preserve-time-stretch` | `engine/pitch_shift` + a new pure stretcher module, `engine/voice.{h,cpp}`'s Preserve read path | **Two shared files in the wave, named rather than discovered at merge.** `src/core/instrument/engine/CMakeLists.txt` — T2 declares two new pure libraries and their test targets there, T5 declares one. **And, newly, `src/core/instrument/ui/CMakeLists.txt`** — T1 declares the taper module and its test target, T3 declares the tessellation module and its. All four are append-only additions in separate blocks — **textual merge adjacency, not semantic contention.** Whichever lands second rebases. **Three near-misses that are avoided by construction, and must stay avoided.** (a) **T3's tessellation helper lands in a NEW pure module — explicitly NOT `ui/envelope_overlay`, which T1 now owns**, and not in `editor_internal.h`, which T1 is also editing. The prior wording offered `envelope_overlay` as an option; Ruling 2 removed it, because T1's schematic-axis work rewrites that module's whole time→x map. This still satisfies the phase's geometry-stays-pure criterion, so it costs nothing. (b) **T1 and T3 are disjoint by file but coupled by data, and the coupling has a stated resolution.** T1 owns where an AHDSR's vertices *land*; T3 owns the stroke *between* vertices. T3's tessellation is over φ across a segment's pixel span, so the tapered axis changes nothing about the curve it draws — **but T3's tests must assert against the returned vertices, not against absolute pixel literals**, or they break when T1 lands. Whichever track lands second rebases; expressing T3's assertions relatively makes that rebase free. (c) **T4 touches `deck_groups` but adds only the new row predicate**; it does not touch `sampleDeckGroups`, which W2-T1 and W3-T1 own in later waves, and it does not touch `deck_values`, which is T1's. **Two consumption boundaries worth stating, because they look like collisions and are not.** T1 **consumes** `engine/master_gain`'s dB taper for its whole-dB snap and does not edit it; T2 does not touch it either. And T2's payload rung is the wave's only format change — T1's taper and ceiling changes are persistence-neutral by construction (the payload stores raw engine doubles). **Both of the phase's DSP unknowns are in this wave** — T2's limiter and T5's stretcher. That is deliberate: they are the two tracks whose gate can fail, and failing in wave 1 is recoverable in a way that failing in the last wave is not. #### Γ-W1-T1 — `knob-interaction-law` **Goal.** One consistent, unit-category-driven interaction and taper rule across every variable control, **over a stage-time range raised 2 s → 10 s**, landed **before** any new control is added so the new ones are authored into it rather than retro-fitted — and before any parameter is declared, so the law is what the host is handed rather than something the host has to be reconciled with later. **Spec:** `docs/product/instrument-control-surface.md` §4, **§4.3.1 (the 10 s ceiling and the overlay-legibility design — new, read it before scoping this track)**, and `docs/product/parameter-automation.md` §8 (the one-way-door sweep this track discharges). **Surface boundary — owns:** a **new pure taper module** under `core/instrument/ui/` (the ms/semitone/exponent maps, extracted so they have one home), `core/instrument/ui/deck_values` (the bindings, the snap-unit table, `resetDeckParam`), `core/instrument/ui/envelope_overlay` (the ceiling constant **and** the AHDSR schematic axis) and `core/instrument/ui/envelope_edit` (its drag inverse), `core/instrument/ui/param_slider` (the drag law), `shell/instrument/editor_input_*` (modifier read + re-anchor), `shell/instrument/editor_controls.cpp`'s `envClampBounds` **only** (it reads `kEnvTimeMaxSeconds`), and the modifier-reading helper the three input paths share. **Does not own** any deck descriptor, any parameter, the waveform painter, or `engine/master_gain` (consumed, not edited). **Why this track does NOT split, asked and answered.** Ruling 2 makes it materially bigger — tapers, modifiers, re-anchor, reset bypass, the ceiling, and the overlay's schematic scale. Two splits were considered and both are **serial, not parallel**, so neither buys any concurrency: an *interaction* half (modifiers, snap, re-anchor) needs the *domain* half's taper and snap-unit table to exist first; and a standalone *overlay-axis* track needs the taper module and the final ceiling before it can define a stage's slot width. Splitting would therefore cost a wave and gain nothing, while putting the single most identity-critical function in the phase across a wave boundary — the same function the host will normalize against three waves later. **The seam that matters is internal and is a deliverable: the taper is extracted into its own pure module**, which is what makes "the taper IS the host-facing normalization" structurally true rather than a comment. The ~600-line ceiling is a per-file bar, and the extraction is what keeps every file under it. **Behavior.** - **Shift snaps to whole numbers in the control's displayed unit**; **Ctrl scales the drag by 0.05**; **Shift+Ctrl = Shift wins** (Ctrl is ignored — with an integer-quantized output a finer drag yields the same sequence, so this is identity, not a compromise). - **Snap unit by category:** ms knobs → whole ms; semitone knobs (incl. Rate, when it arrives) → whole semitones; percent/fraction knobs → whole percent; the 12 curve-exponent inner dials → whole numbers (which puts 1.0, the linear neutral, one snap away); master gain → whole dB; already-integer controls unchanged. Full table in the spec §4.2. - **Mid-drag modifier transitions re-anchor** — on every press *and* release during an active drag, the current value becomes the anchor value and the current cursor position the anchor position. The value is continuous across the transition; only the rate changes. Without this the grab-anchored absolute drag (`kKnobDragRangePixels = 128`) jumps by `(1 − 0.05) ×` the accumulated delta. - **Millisecond knobs become log-scaled.** Exactly 0 s at norm 0 and exactly `kEnvTimeMaxSeconds` at norm 1, monotone throughout; **10 ms lands within 0.12–0.20 of travel and 100 ms within 0.42–0.52**. - **The stage-time ceiling moves 2.0 s → 10.0 s** (Daniel, reversing Γ-F3): `kGateStageMaxSeconds` (`envelope_overlay.h:85`) and, through it, `kEnvTimeMaxSeconds` (`deck_values.h:22`). **The two move together or not at all** — `deck_values.h` reads the overlay's constant rather than restating it precisely so they cannot drift (`deck_values.h:19-22`). The taper's landmarks above are fit against the **new** ceiling, which is why the ceiling cannot be a follow-up: fitting the taper twice is the only other way to get there. - **`resetDeckParam`'s bypass becomes MANDATORY rather than merely required-anyway.** `deck_values.h:42-46` records that exact default recovery depends on the ceiling being a power of two; **2.0 is, 10.0 is not**, and the log taper compounds it. Nothing here may be "simplified" back into a norm round-trip under any circumstance. - **NEW, and the sharpest requirement in the track: every default must have an EXACT normalized preimage under its taper.** `ParameterInfo::defaultNormalizedValue` (Γ-W4-T1) is normalized, so a host's reset-to-default arrives as `toPlain(defaultNorm)` — and **the host has no `resetDeckParam` bypass to use**. The bypass fixes the editor's reset and cannot fix the host's; only exactness in the map itself makes the two land on the same value. This binds the taper's *shape*, so it belongs here and cannot be handed forward. Master gain's unity (≈ 0.714 norm) is the case where a hair off is audible. - **The AHDSR overlay's schematic axis becomes the taper — the ceiling's real cost, and it is design work, not a constant change.** Each of the four timed stages gets an equal slot and today maps seconds across it linearly (`gatePxPerSecond`, `envelope_overlay.cpp:33-34`). At 2 s a 30 ms attack is 1.5 % of its stage's domain; **at 10 s it is 0.3 %, under a pixel at the floor width.** The fix: a stage's slot width becomes `slotPx × taperNorm(seconds)` instead of `slotPx × seconds / ceiling`, so a node's position within its slot **is** its knob's needle position. Legibility becomes ceiling-independent by construction; the one-model invariant gets stronger rather than strained; and **the drawn curve is unaffected**, because the taper decides only where a stage's end node lands while φ still runs linearly across the stage's pixel span — so Γ-W1-T3's φ^p trace composes with it rather than fighting it. **The AHD policy is untouched**: an AHD maps 1:1 onto the waveform's own PCM-aligned time axis and stays linear in seconds. Two alternatives (content-fit auto-scale; a minimum drawn stage width) were considered and rejected — spec §4.3.1 names why, and neither is to be reintroduced as a "simplification." - **`envelope_edit`'s drag inverse must remain the EXACT inverse of the draw.** Both read the same taper module; a node dragged to a pixel and the knob's value at that pixel are one number, not two that agree. - **The taper is EXTRACTED into its own pure module**, with its own `_tests` target, because it now has three consumers in two different dependency layers: `deck_values` (which sits above `envelope_overlay`), `envelope_overlay`/`envelope_edit` (which sit below it), and — from Γ-W4-T1 — the host. Leaving it inside `deck_values` would force an inverted include edge. **Do not solve that by copying the map.** - **Semitone knobs become log2/centre-expanded.** Symmetric, exactly 0 at centre, exactly ±`kPitchDepthMaxSemis` at the ends, monotone; **±7 st reached at 50–58 % of each half-travel**. - **`resetDeckParam` bypasses the taper** — it writes the default value directly instead of round-tripping through `norm → value`. This *removes* the power-of-two dependency the header currently documents rather than working around it; that comment (`deck_values.h:42-46`) becomes wrong and must be rewritten. - **Scope is the parameter, not the widget.** Deck knobs (outer ring and inner dial), envelope stage nodes and curve knots all honour it — they are surfaces onto one model, and a snap on one but not the others is a divergence. **Waveform markers are explicitly excluded**: they carry a shipped zero-crossing snap on the same modifier space and their domain is frames. **Acceptance criteria.** - Every taper change is verified **persistence-neutral**: a project saved before the change reopens with bit-identical stored values and identical audio; only needle angles move. - Holding Shift mid-drag on each unit category lands the documented whole unit; releasing it does not jump the value. - Holding and releasing Ctrl mid-drag is continuous — no step at either transition. - Double-clicking any knob (outer ring and inner dial independently) lands **exactly** on its default at every taper, verified against a default-constructed `PlaySeconds` rather than a round trip. - The log/log2 landmark positions above are asserted in the **taper module's** own tests, and hold at the **10 s** ceiling — the fit is against the new ceiling, not the old one. - **Every default round-trips exactly through `norm → value`**, asserted per unit category against a default-constructed `PlaySeconds` and against `master_gain`'s unity. This is the criterion Γ-W4-T1 will declare `defaultNormalizedValue` from; it fails here, not there. - **A stage time of several seconds is reachable by hand with no loss of resolution below 100 ms**, and `kEnvTimeMaxSeconds == kGateStageMaxSeconds` is asserted, not assumed. - **A project saved at the 2 s ceiling reloads with identical stored seconds and identical audio** — the ceiling change is persistence-neutral for the same reason the taper is. - **The AHDSR overlay reads legibly at both ends of the new range**: a default 3 ms attack is a visible, grabbable node at the floor width, and a 10 s decay still lands its end node at its slot's edge. Assert the node separation, then judge the result by eye in the DAW. - **The overlay's drag inverse is the exact inverse of its draw** at the tapered axis — `nodeAtPoint` / `resolveNodeDrag` and `buildEnvelopePolyline` round-trip. - **The AHD 1:1 policy is unchanged**, asserted: a sustain-less envelope's x-axis stays wall-clock over the waveform. - **The taper module is pure, CTest-covered, and is the ONLY definition of each map** — a grep finds no second copy in `deck_values`, `envelope_overlay`, or the shell. - **The filter's four `*Norm` controls are untouched by the taper pass** — cutoff, Q, morph and drive are already wire-frozen in payload v9; a regression baseline proves their audio is unchanged. - One shared modifier-read helper serves all drag surfaces; no second modifier grammar exists. **Open questions.** - **No [Daniel] questions.** Fork **Γ-F3 is REVERSED**: the ceiling moves to **10.0 s, in this track.** Daniel's *"a horrifically long decay with tight exp"* is the case it serves, and the `docs/TODO.md` entry that carried it is discharged rather than deferred again. **The reversal's cause is Ruling 1** — a range endpoint is host-facing normalization, free to move now and permanently expensive after Γ-W4-T1. Both of the prerequisites the deferred entry named are in this track anyway: the log taper (which is what makes a higher ceiling usable at the low end rather than unusable) and the reset bypass (which retires the power-of-two dependency — 2.0 is a power of two, 10.0 is not). The engineer should know the reset bypass is now doing triple duty and must not be "simplified" back into a norm round-trip under any circumstance. - **[propose at review]** the exact shape of the taper, subject to the landmark bounds **and** the exact-default-preimage requirement. Those two together are tighter than either alone, and the second is easy to satisfy by accident and easy to lose in a refactor — **assert it, do not observe it.** - **[propose at review]** whether the tapered schematic axis wants a visible tick or gradation cue, now that it is no longer linear in time. The plan's lean is **no** — the ms labels carry the number and the editor's no-decoration policy stands — but a reader who finds the axis illegible in the DAW should say so rather than silently adding one. #### Γ-W1-T2 — `master-bus-audio` **Goal.** The master limiter and the meter's **audio and publication halves**, plus **the plugin's first latency reporting** — no editor drawing. Landing the audio ahead of the deck is what lets Γ-W3 draw against real published state instead of a stub. **Spec:** `docs/product/instrument-control-surface.md` §3.1, **§3.1.1 (latency — read this first; it was rewritten when Γ-F6 closed, so an older reading of it is wrong)**, §3.2–3.3, §3.5, §7.10, §7.11, §8.2. **Surface boundary — owns:** a new pure limiter module and a new pure meter-ballistics module under `core/instrument/engine/` (each with its own `_tests` target), `shell/instrument/reasampler_processor` (the chain, the published block state, **and the `getLatencySamples` / `restartComponent(kLatencyChanged)` path**), and **the phase's FIRST params-payload rung** (the limiter enable flag). **Does not own** MASTER's deck geometry or any drawing — that is Γ-W3-T1. **Read `kParamsPayloadVersion` on `dev` and take the next rung above it rather than assuming the number** — Phase Ξ ran ahead of this plan's sequencing, so the plan is not the record of what the ladder currently carries. On `dev` as of 2026-08-01 that resolves to **v14**. **Behavior.** - **Chain:** `voice mixer → master gain (existing ramped multiply) → limiter (bypassable) → output bus`, with the meter tapped at the **bus output, post-limiter**. - **Limiter: a single toggle, no configurable controls.** Baked ceiling **−0.3 dBTP**. Default **off**. **No makeup gain, ever, of any kind** — transparent at rest. Stereo-linked detection (max |L|,|R| drives one gain) so the image is not moved. - **True-peak detection is sidechain-only** — an oversampled detector in the sidechain, never oversampling the signal path. Factor is the engineer's call under the measure gate. - **Lookahead, with DYNAMIC reported latency (Γ-F2, ruled).** `getLatencySamples()` returns **0** when the limiter is off and **the lookahead in samples** when it is on; the toggle calls `IComponentHandler::restartComponent(kLatencyChanged)`. **None of this exists today** — there is no `getLatencySamples` override, no `kLatencyChanged`, and no `restartComponent` call site anywhere in `src/`; the plugin ships the SDK default of 0. This track introduces the plugin's first latency reporting. - **The restart is routine; the fencing is against a standing scar, not against the flag.** Dynamic latency reporting is ordinary VST3-instrument behaviour and REAPER handles it as a matter of course. The SDK's deactivate/reactivate requirement (`pluginterfaces/vst/ivsteditcontroller.h:105-108`) is the normal contract. **What makes the cycle expensive here is this plugin's own `setActive`** — reactivate calls `reloadInstrument()`, a bridge read plus a full WAV re-decode (`reasampler_processor.cpp:89-97`), where a typical plugin only allocates buffers; deactivate frees `live_`/`draining_`/graveyard (`:98-107`) for a documented reason (ghost sustained voices). **Γ-F6 is ruled: ship it — the toggle is a patch-design gesture, not a during-playback one.** Do **not** build a constant-reported-latency fallback and do **not** gate the deliverable on a measurement. The reduction of that self-inflicted cost is filed in `docs/TODO.md` ("Decouple the instrument reload from VST3 activation") with its trigger condition; it is out of scope here. The four requirements below survive as engineering hygiene against the `kIoChanged` scar, and all four are acceptance criteria: 1. **Verify the whole call sequence against the vendored Steinberg SDK** before writing it, including the ordering rule that the new latency is what `getLatencySamples` returns *after* `setActive(true)` — so **the reported value must derive from persisted state, not from a transient the deactivate clears.** 2. **Prove the restart does not disturb the output bus arrangement.** The output stays one permanently-stereo bus, never renegotiated. 3. **Ship a regression test in the spirit of `testDualMonoStereoSampleRendersCentered`** — a dual-mono capture rendered across a limiter toggle stays centered, L ≡ R. 4. **`restartComponent` is never called from `process()`.** Main/UI thread only, and coalesced so repeated clicks produce one restart per settled state. **This is NOT the change `reasampler_processor.cpp:66-68` forbids.** That warning is against reintroducing per-mode **bus** renegotiation (`kIoChanged` class), which panned a dual-mono capture hard right in the host's pin re-routing; `kLatencyChanged` is a different flag and the bus is untouched. But the precedent — mid-session `restartComponent` in this plugin has already shipped one real regression — is exactly why (2) and (3) are non-negotiable. - **Flipping the toggle during playback: apply immediately, do NOT defer to a transport boundary** (product ruling, spec §3.1.1). A deferred restart leaves the plugin misaligned by the lookahead with no visible cue, which is worse than a visible interruption; and the host, not the plugin, schedules the deactivate/reactivate anyway. **Daniel has accepted the interruption outright** (Γ-F6) — it is not a case to design for. Two things remain in scope, and neither is a mitigation for it: - **A short (≤ 10 ms) equal-gain crossfade over the engage/disengage.** Kept as a *quality* measure, not a mitigation: a limiter engaging is a gain-path change, and this codebase already ramps every gain-path change (`kGainRampSeconds`, `ValueRamp`). It also earns its keep independently of the restart, because **we do not control when the host acts on the request** — our own transition must be clean in the window before it does. - **The limiter enable is classified NOT automatable** (`docs/product/parameter-automation.md` §3.8) so nothing can flip it at rate. It is also **not** the plugin's `kIsBypass` parameter. - **Per block the processor publishes, as relaxed atomics:** per-channel peak `max|x|`, a latched clip flag, and the block's maximum gain reduction. **No dB conversion, no ballistics, no hold timers on the audio thread** — the UI converts and runs ballistics from block peaks and elapsed time. This widens the existing advisory-peak pattern (`reasampler_processor.h:109-113`), which is not reusable as-is. - **Meter ballistics (pure, unit-tested):** instantaneous rise; **fall 20 dB/s**; peak-hold latched at the running max, **held 1.5 s**, then falling at the same rate; scale **linear in dB over −60…+6 dBFS**; clip latches at block peak ≥ 0 dBFS and is cleared on request. - **The `ComponentState` payload rung** appends the limiter flag as a strict suffix on the existing discipline; the preceding version's blob is a strict prefix and lifts to bypassed. **Acceptance criteria.** - **With the limiter bypassed the rendered output is byte-identical to the pre-change build**, asserted by a regression baseline, not by ear. - With the limiter engaged, no output sample exceeds the ceiling on program material that exceeds it by up to +12 dB; with it bypassed and gain driven, the output does exceed 0 dBFS (proving the toggle is doing the work). - **Nothing is louder at rest with the limiter on.** A signal that never reaches the threshold is bit-identical engaged and bypassed. - No allocation, no lock, no transcendental on the per-sample path; the measure-and-report gate reports per-voice-block CPU with the limiter engaged at 32 voices. - The meter-ballistics module is pure and CTest-covered: rise, 20 dB/s fall, 1.5 s hold, clip latch/clear, and the dB↔pixel map are all asserted without a host. - A project saved before this change reopens with the limiter bypassed and sounding identical. - **`getLatencySamples()` returns exactly 0 with the limiter off**, and the lookahead in samples with it on — asserted against the persisted flag, and correct across a deactivate/reactivate cycle. - **A dual-mono capture rendered across a limiter toggle stays centered** (L ≡ R), and the output bus arrangement after a latency-change restart is identical to before it. - **The plugin emits no hard step at the toggle** — the engage/disengage crossfade is asserted on a rendered signal, not judged by ear. **Open questions.** - **No [Daniel] questions. Fork Γ-F6 is ruled** — dynamic latency ships as specced, the deactivate/reactivate is accepted, and there is no fallback design and no measurement gate. Do not reintroduce either; the constant-reported-latency option is closed, not shelved. - **[verify]** `temp_cortex/` has already been assessed and **rejected** (spec §3.5) — do not re-litigate it, and do not transplant from it. - **[record, not a gate]** While the limiter is in REAPER under your hand, note what the restart actually costs — do notes cut, is the re-decode perceptible, does transport hiccup — and record it in this track's review. It is **not** a gate on shipping and no outcome changes the design; it is the trigger-condition evidence for the `docs/TODO.md` entry "Decouple the instrument reload from VST3 activation," which is where that cost gets reduced if it ever matters. Do **not** restructure `setActive` here: its destructive shape is deliberate and its reasoning (ghost sustained voices on reactivate) is documented at the call site. #### Γ-W1-T3 — `contour-trace-curves` **Goal.** Staged envelope segments draw as the curve their exponent defines, so the mid-segment knot stops floating off its own trace. **Spec:** `docs/product/instrument-control-surface.md` §5. **Surface boundary — owns:** `shell/instrument/editor_paint_waveform.cpp`'s staged-envelope trace and a **new pure tessellation module** for it. **Does not own** the loop/crossfade marks (Γ-W2-T2), `envelope_overlay`'s vertex model, or the drawn-EG (spline) trace. **The helper's home is now constrained, not a choice.** `ui/envelope_overlay` was previously offered as a candidate home for the tessellation helper; **Γ-W1-T1 now owns that module** (the AHDSR schematic axis, per Ruling 2), so the helper lands in a **new** pure module under `core/instrument/ui/`. T1 also owns where an AHDSR's vertices land — this track owns only the stroke *between* vertices, and tessellates over φ across a segment's pixel span, so the tapered axis changes nothing about the curve drawn. **Express this track's assertions against the returned vertices, not against absolute pixel literals**, and the rebase onto T1 is free. **Behavior.** The defect is verified: `editor_paint_waveform.cpp:218` drops knots (`if (v.knot) continue;`) and joins the remaining vertices with straight strokes, and `curveMap` is never called in the paint path even though the exponent is in scope at `:211`. Knot *positioning* already honours the exponent via `curveMidLevel` (`envelope_overlay.cpp:94-105`) — that divergence is the visible symptom. The fix draws each sloped stage through **the same `curveMap` the audio uses**, so trace and sound cannot diverge; tessellation approach is the engineer's call. **Acceptance criteria.** - **At every exponent the knot's centre lies on the trace, within 1 px** — the reported defect, stated as the gate. - **At exponent 1.0 the segment is visually identical to today's straight line.** - No visible faceting at the widest segment the canvas can produce; a fixed low tessellation count is not acceptable at full width. - All three envelopes, both play modes, all sloped stages (attack/decay/release) — one paint path, one fix. - The established trace grammar is unchanged: one weight, `kEnvTracePx = 2.0`, through the analytic stroker. Both overlay layout policies (AHDSR right-anchored schematic, AHD 1:1) are honoured unchanged. The spline overlay's own trace is untouched. - **Audio is unchanged** — this is a drawing defect only; a regression baseline proves it. #### Γ-W1-T4 — `editor-floor-and-row-law` **Goal.** Commit the **canvas** — the window floor, the width budget it is derived from, and the row every deck group belongs to — so every other UI track in the phase is drawn, tested and judged at the final window size. The **arrangement** inside that canvas is Γ-W3-T1's. **Spec:** `docs/product/instrument-control-surface.md` §1.1 (the two categories), §1.2 (the floor arithmetic block), §1.6 (the headroom ledger), §7.1 and §7.4 (the two invalidated `knob_deck.h` notes). **Surface boundary — owns:** `core/instrument/ui/sample_bands.h` (`kEditorMinWidth`), `core/instrument/ui/knob_deck.h` (the declared budget constants and the two invalidated header notes), `core/instrument/ui/deck_groups.{h,cpp}` (**the new row predicate only**), and the five test fixtures that read the floor — `test_sample_bands.cpp`, `test_deck_groups.cpp`, `test_knob_deck.cpp`, `test_sample_chrome.cpp`, `test_keyboard_strip.cpp`. **Does not own** `layoutDeck` / `deckRowCount` / `deckHeight` behaviour, the justification law, any descriptor, MASTER's inventory or interior, any painter, or any parameter. It changes **no drawing code at all.** **Behavior — what it commits.** - **`kEditorMinWidth` 980 → 1190. `kEditorMinHeight` stays 680** (Γ-F1). - **Three declared budget constants in `knob_deck.h`:** the row block both rows will justify inside (**1020**), the right-anchored spanning deck's reserved width (**MASTER 142**), and the ceiling (**1280**). These are *declarations of budget*, not measurements — nothing computes them from a descriptor, and Γ-W3-T1's job is to prove its content fits inside them. - **The floor is derived, not asserted as a literal.** `1020 + kDeckGroupGap(12) + 142 + 2·kPad(8) = 1190`. `kEditorMinWidth` stays a literal in `sample_bands.h` — **do not add an include edge from `sample_bands` to `knob_deck`**, which would invert the allocator's deliberate independence from the deck (it takes `deckHeight` as a *parameter* for exactly that reason). The identity is asserted in `test_deck_groups.cpp`, which already includes both headers. This is the Θ-W6-T1 derived-floor precedent, landed once and never rewritten. - **Row membership becomes a property of the group id:** `DeckRow { Sound, Contour, Spanning }` + `deckRowFor(DeckGroupId)` in `deck_groups`, an **exhaustive switch** on the `isLiveDeckParam` discipline, so a future group is a compile error rather than a silent default. Partition: **Sound** = PITCH/RATE, FILTER, VELOCITY, VOICE; **Contour** = PITCH ENV, FILTER ENV, AMP ENVELOPE; **Spanning** = MASTER. **Nothing consumes it until Γ-W3-T1** — that is the seam, and it is why the predicate is safe to land now: **membership is a property of the group, width is a property of the descriptor**, and only the widths are still moving. - **Γ adds no new deck group**, so no later track amends this predicate. **The seam, stated as what this track can and cannot assert.** *Can assert today:* - The derived floor identity above, and `kEditorMinWidth ≤ 1280` with **90 px** of headroom. - `kEditorMinHeight == 680`, asserted so no later track drifts Γ-F1's ruling. - `deckRowFor` is total over `DeckGroupId` and yields exactly the partition above. - **Row 2's natural width already fits the block, in both play modes:** 252 + 312 + 312 = **876 ≤ 1020**, leaving both its gutters ≥ `kDeckGroupGap`. Mode-stable because FILTER ENV's and AMP's reserve slots hold them at 312 in Gate and Trigger alike. - **MASTER's reserve is not yet spent:** `deckGroupWidth(MASTER) == 72 ≤ 142`. - At the floor, deck band **216** and waveform band **358** — the reflow's 112 px arrives here, two waves early (see the interim layout below). *Cannot assert yet, and must not force:* - **Row 1's natural width does not fit the block.** Today it is PITCH 150 + FILTER 524 + VELOCITY 192 + VOICE 164 = **1030**, against the 1020 block. The 50 px deficit is exactly what the two descriptor changes buy: PITCH → PITCH/RATE **+42** (Γ-W2-T1) and FILTER's `Band|Notch` moving to the caption corner **−92** (Γ-W3-T1), netting **980**. Record the target and the two contributions as a test comment; **assert the fit in Γ-W3-T1, and do not pre-empt either descriptor change to close it early.** - Gutter distribution, the filter tie-line at x = 636, flush outer edges, MASTER's interior and its meter — all Γ-W3-T1. Every one of them measures a descriptor that does not exist yet. **The interim editor, stated exactly so it is not filed as a defect.** At the new floor, `availWidth = 1190 − 2·kPad = 1174`, and the **unchanged** greedy whole-group wrap packs: ``` row 1 PITCH 150 · PITCH ENV 252 · FILTER 524 = 950 used, 224 px ragged right row 2 FILTER ENV 312 · AMP 312 · VELOCITY 192 · VOICE 164 · MASTER 72 = 1100 used, 74 px ragged right ``` **Two rows, not three** — so the deck band is already 216 and the waveform already draws at its final 358 px, in both Gate and Trigger. After Γ-W2-T1 lands PITCH/RATE the pack is row 1 = 992, row 2 unchanged; still two rows. The composition is wrong in exactly the way the reflow exists to fix — PITCH ENV sits up with the sound decks, VOICE and MASTER sit down with the envelopes, MASTER is still a single-height 72 px box, and both rows are left-packed with dead space at the right. **Worse than today in composition, better in proportion.** That is the accepted transitional state for the rest of the phase. **Do not convert the two-row interim into a claim.** It is a coincidence of the greedy wrap at exactly this width, not a guarantee — which is precisely why Γ-W3-T1's criterion is "two rows **by construction**, asserted against the group inventory, not observed as a wrap outcome." `testDeckFitsInsideTheEnforcedMinimumWindow` currently asserts `deckRowCount == 3`; relax it to an **upper bound** (`<= 2`), which is a real regression canary throughout the interim and is subsumed by Γ-W3-T1's exact claim. An exact `== 2` here is acceptable only with a comment naming it as a wrap outcome the reflow replaces. **Acceptance criteria.** - **The floor is 1190 × 680, reached by a derived test over the three budget constants**, not by a literal — and the derivation is the one Γ-W3-T1 later reads rather than a second copy. - **Headroom is exactly 90 px** against the 1280 ceiling, asserted. - `deckRowFor` is exhaustive over `DeckGroupId`; adding a group without classifying it fails to compile. - Row 2's natural width and MASTER's unspent reserve are asserted, in **both** play modes. - **All five floor-reading test fixtures pass at the new floor** — including the chrome row, whose title slot gets *more* room at 1190, not less. - **No drawing code changes, no descriptor changes, no parameter changes, no audio change.** A regression baseline proves the last of those trivially. - The two invalidated `knob_deck.h` notes (§7.1's fourteen-pixel headroom figure, §7.4's cells-and-floor pairing) are **re-derived against the new floor, not deleted** — §7.4's restatement is *the deck's cell metrics AND its group/row composition both drive `kEditorMinWidth`; none of the three may move alone.* **Open questions.** **No [Daniel] questions.** **[propose at review]** whether the three budget constants belong in `knob_deck.h` (the deck owns the row block and the spanning-deck reserve) or in `sample_bands.h` (the allocator owns the floor they derive). The plan's lean is `knob_deck.h` with the identity in the test, because it adds no include edge; either is defensible, but the *derivation must live in exactly one place*. #### Γ-W1-T5 — `preserve-time-stretch` **Goal.** A real pitch-preserving time-stretcher for Preserve mode, written from established state-of-the-art literature — landed **before** the control that drives it, so Rate ships onto a finished engine rather than onto a disposable stand-in. **Spec:** `docs/product/instrument-control-surface.md` §2.5. **Moved from Γ-W4-T1 (Daniel, 2026-08-01).** It is the longest pole in the phase and has zero dependency on any UI work. **The consequence is the interesting one: it inverts the relationship with Rate.** Under the old order the stretcher was Rate's quality upgrade and Γ-W2-T1 shipped an interim resample-and-cancel path to make Rate complete on day one; under this order the stretcher is Rate's **prerequisite** and **the interim path is not built at all.** Skipping a stand-in that was only ever going to be deleted is the win; see Γ-W2-T1's named contingency for what happens if this track's gate slips. **Precedent for landing a DSP module ahead of its consumer:** Θ-W1-T3 (`filter-dsp-port`) landed the filter DSP as a standalone pure module a wave before Θ-W2-T1 wired it into the voice path, for the same reason — the unknown is the DSP, not the wiring. **Surface boundary — owns:** `core/instrument/engine/pitch_shift` and whatever new pure module the stretcher needs (each with its own `_tests` target), plus `voice.{h,cpp}`'s Preserve read path. **Does not own** any parameter, any UI, the varispeed path, or the deck. It adds no `ComponentState` field and takes **no rung of the payload ladder**. **Behavior and constraints.** The algorithm is **the engineer's call under a measure-and-report gate — this plan deliberately names none.** The constraints: - **The stretch ratio is an argument, not a parameter.** Nothing publishes a non-unity ratio until Γ-W2-T1's Rate knob does. Until then the Preserve read path runs at ratio 1.0 and must be **bit-identical to the shipped Preserve read** — a stronger and cheaper regression gate than the old plan's A/B-against-an-interim-path, because the baseline is a build that exists. - **CPU stance (Daniel, verbatim intent):** *"we should be efficient but accept the cost of high-quality algorithm choices. It's 2026, most people's computers can handle audio with ease. Just don't be wasteful."* - **RT-safe:** no allocation, no I/O, no lock in `process()`; buffers sized at voice allocation or at the off-audio-thread reload, on `pitch_shift`'s existing pre-warm precedent. - **Per-voice state, holding up at the 32-voice ceiling.** The gate is 32 simultaneous Preserve voices at 50 % and 200 %, not one voice at 100 %. - **No new third-party dependency** (`pitch_shift`'s standing property). - **No dispatch on the per-sample path** — concrete, inlineable types; no `IStretcher`. - **Onset behaviour is a regression surface.** GA2 eliminated Preserve's ~25 ms onset latency by priming the ring with the actual upcoming source. **A stretcher that reintroduces an onset delay or a first-frame smear is a regression, not a trade-off.** **Acceptance criteria.** - **Ratio 1.0 with no shift is bit-identical to the shipped Preserve read**, asserted by a regression baseline — the null case, and the criterion that makes landing this ahead of Rate safe. - Preserve speaks on frame 0 — no added onset latency, no first-frame smear, in any ratio/shift combination. - No audible metallic or phasey artefacting on sustained tonal material at ±6 st and 75–133 % ratio; transient material at 50 % / 200 % is no worse smeared than **varispeed playback at the equivalent ratio** — the honest "what does preserving pitch cost" reference, and the one that needs **no disposable implementation built to serve the comparison.** - The Gate sustain-loop contract is unchanged: **loop the source, shift the output** — loop points remain source-frame facts. - **Measure and report before the algorithm is final:** per-voice CPU at 32 voices, added latency (must be zero at the onset), and A/B recordings on three material classes (one-shot, tonal sustain, full-mix bounce). Report to Daniel; the choice is not final until he has heard the A/Bs. **Open questions.** **[propose, with a measurement step]** the algorithm family itself. **[verify]** that `core/instrument/CLAUDE.md`'s *"`WDL_Resampler` is not a Preserve engine — never wire it as the duration-preserving path"* is honoured: under Preserve, Rate legitimately changes duration, so a resampled read is an explicit duration control — but the *pitch-preserving* mechanism must not be a resampler. **No [Daniel] questions.** --- ### Γ-W2 — New controls, and the overlay's marks **Depends on Γ-W1 for — four dependencies, two of them new:** 1. **T1 ← W1-T1 (taper law).** Rate and Pitch must be authored into the finished taper/modifier law, not retro-fitted into it, and the semitone taper must exist before a second semitone knob does. 2. **T1 ← W1-T5 (the stretcher) — NEW, and the reason the interim path is gone.** Preserve Rate has no engine without it. Under the prior four-wave order this dependency ran the other way and was paid for with a disposable resample-and-cancel stand-in; the resequencing inverts it. **Rate must not ship before its Preserve engine.** 3. **T2 ← W1-T3 (the contour trace).** Both write `editor_paint_waveform.cpp`; running them together is a merge fight in one file. 4. **T2 ← W1-T1 and W1-T4, weakly.** W1-T1 also edits `editor_input_waveform.cpp` (the modifier read), which T2 rewrites for marker hit-test routing — serial, so not a conflict, but T2 rebases onto it. And T2's "the enable costs no window width" criterion is now asserted against **W1-T4's** derived floor test rather than one this track has to write. T1 additionally inherits `engine/voice.{h,cpp}` from W1-T5 — a **hand-off, not a conflict**: W1-T5 defines the Preserve ratio seam, and T1 feeds it. Serial across waves by construction. **Disjointness — re-verified against this wave's membership, not carried over.** Both tracks stayed in W2 and nothing entered or left it, so the prior finding is re-checked and stands. T1 owns the parameter model, the engine and the deck descriptors; T2 owns the waveform band's marks and their pure geometry **and the chrome row's loop enable**. The two are disjoint at the module level with **one named exception: `shell/instrument/editor_session.cpp`.** T1 may touch it for the third commit tier's routing; **T2 owns `pickedMarkers` and `applyMarkers` there and nothing else.** The partition is by function and the two do not overlap — **textual merge adjacency, not semantic contention** — but it is a shared file in a phase whose wave boundaries are otherwise single-writer surfaces, so it is stated rather than discovered at merge. Whichever track lands second rebases onto the first. No *new* in-wave adjacency was created by the resequencing: T2 touches neither `deck_values` nor `deck_groups` nor `voice`. **One cross-wave hand-off, new with Ruling 2 and NOT a contention.** Rate's taper — linear in semitones over ±12, the stated exception to the centre-expansion law — belongs in the **taper module Γ-W1-T1 extracts**, since that module is the one home of every map. T1 therefore appends a law to a module a previous wave created. Serial across waves by construction, the same shape as its `engine/voice.{h,cpp}` hand-off from W1-T5. **What would be wrong is a second taper defined inside `deck_values`' binding** — one home, appended to, not forked. **The format ladder stays clean.** The loop enable maps onto the existing `SampleLoop::hasLoop`, which is already persisted and whose `start`/`end` are already written unconditionally — **no new field, no version bump** — so T1 keeps sole ownership of **the phase's second payload rung** exactly as specced (v15 on `dev` as of 2026-08-01; read the ladder rather than assuming the number). #### Γ-W2-T1 — `pitch-rate-deck` **Goal.** PITCH becomes **PITCH/RATE**: three knobs (`Key Trk | Rate | Pitch`) under the existing Varisp|Presrv toggle, with both new controls wired through the engine. **Spec:** `docs/product/instrument-control-surface.md` §2. **Surface boundary — owns:** `core/instrument/engine/play_params.h` + `core/instrument/map/play_seconds.h` (the two new fields), `core/instrument/map/component_state_io` + `params_payload` (**the phase's SECOND payload rung** — v15 on `dev` as of 2026-08-01; read the ladder, do not assume the number), `core/instrument/engine/voice.{h,cpp}` (the compounding and the note-on latch), `core/instrument/ui/deck_groups` (the PITCH/RATE descriptor **and** the three-state live predicate), `core/instrument/ui/deck_values` (the two new bindings). **Does not own** the deck's row layout — that is Γ-W3-T1 — nor the time-stretcher itself (Γ-W1-T5, already landed by the time this track runs). **Behavior.** - **Rate: 50 %–200 %, default 100 % at true knob centre, exponential taper** — 50 % = −12 st, 200 % = +12 st, musically symmetric. This is **linear in semitones over ±12** and is the stated exception to W1-T1's centre-expansion law (which applies to semitone knobs whose throw exceeds ±12). - **Pitch: a baseline pitch offset, ±24 semitones**, centred, on W1-T1's centre-expanded semitone taper. **Reads `kPitchDepthMaxSemis`; does not mint a second constant.** - **Varispeed:** keytrack ratio × rate ratio × pitch-offset ratio **compound into a single read-increment multiply**; the rate offset applies to the varispeed pitch. Composes with the pitch envelope's existing per-frame `ratio_` multiply — **no new per-sample stage**. - **Preserve:** rate is an **absolute** value driving **duration only**; keytrack and pitch offset drive the pitch shifter. **Rate drives the stretch ratio Γ-W1-T5's stretcher already consumes — there is no interim path.** The stretcher is this track's prerequisite, not its successor; the resample-and-cancel stand-in the prior plan carried is retired unbuilt (see Open questions for the contingency). `core/instrument/CLAUDE.md`'s "never wire `WDL_Resampler` as the duration-preserving path" is honoured by construction. - **Rate is latched at note-on**, delivered by a **third commit class**: published into the live block like any live parameter, read only by `snapLive`, never by `applyLive`. `isLiveDeckParam`/`liveCommitFor` widens from two states to three (`Live` / `NoteOnLatched` / `Reload`) in that one predicate — **not** a second table, and **not** the reload tier (a swept knob must never trigger a WAV re-decode). **Record the reason in the header:** loop resolution and contour mapping are note-on folds, so live rate means re-folding a resolved loop and re-mapping a contour mid-note. - **Pitch is live** — under Varispeed one more factor in a multiply the pitch envelope already performs; under Preserve an addend to a shift the pitch envelope already modulates. - **Loop points scale with rate; contours scale with rate.** Neither rewrites stored values: the loop is source-frame facts traversed at the new increment (Varispeed) or the new read rate (Preserve), and a contour is a function of normalized position. **Staged envelope stage times do NOT scale** — 30 ms is 30 ms at any rate. That asymmetry is deliberate: a contour is of the sample, a staged envelope is of the performance. - **Deck descriptor:** three cells; `captionWidth` **70**, hard ceiling **80** (above that the caption row overtakes the 180 px knob row and the group exceeds 192). If the text will not fit at 80, narrow the `Varisp|Presrv` segments 48 → 44 (ceiling becomes 88) — **do not widen the group**. - **The payload rung** appends both fields as a strict suffix; the preceding version's blob lifts to rate 100 % / pitch 0 st, bit-identical playback. - **Both new `DeckParam`s are classified in the three-state predicate, and that classification is what puts them in the VST3 parameter list three waves later** — Rate `NoteOnLatched`, Pitch `Live`. Γ-W4-T1 derives the exposed set from this predicate rather than from a list of its own, so a mis-classification here is a mis-declared parameter there. **Acceptance criteria.** - Rate at 50 % plays an octave down and half speed under Varispeed; at 200 %, an octave up and double speed. Under Preserve the same settings change duration only — pitch is unchanged within the stretcher's tolerance. **Preserve Rate is a finished feature the day this lands**, because Γ-W1-T5 already shipped its engine; a degraded or inert Preserve Rate is a failed track, not an acceptable interim. - Rate at exactly 100 % and Pitch at exactly 0 st render **bit-identical** to the pre-change build, in both engines. - Shift-drag on Rate lands on whole semitones (so an octave and a fifth are reachable by hand); Shift-drag on Pitch lands on whole semitones; Ctrl gives cents on both. - **A Rate change while a note sounds does not alter that note**; the next note-on takes it. **It does not trigger a reload or an engine rebuild** — assert the tier, not just the sound. - A Pitch change **does** move a sounding note, in both engines. - With a loop set, changing Rate changes the loop's audible period without moving either waveform marker. - The PITCH/RATE group measures **exactly 192 px**; adding the two `DeckParam`s produces a compile error in `isLiveDeckParam`'s exhaustive switch until they are classified. - A project saved at the preceding payload version reopens at rate 100 % / pitch 0 st and sounds identical. **Open questions.** - **None [Daniel].** - **[propose at review]** Rate's clamp behaviour at the range extremes as it meets the stretcher's own ratio bounds — one clamp, resolved where the two meet, not two that can disagree. - **Named contingency, not a plan item, and not to be taken silently.** If Γ-W1-T5's measure-and-report gate has not passed when this track is ready to dispatch, the pre-agreed fallback is the **resample-and-cancel composition** spec §2.5 records — a resampled read with the resulting pitch change cancelled in the existing SOLA shifter — shipped as an interim Preserve path with the stretcher as its later quality upgrade, i.e. a return to the prior four-wave order. **Escalate to Daniel rather than taking it:** it revives a disposable implementation and re-opens the `WDL_Resampler` guardrail conversation, and the whole point of the resequencing was to avoid building it. #### Γ-W2-T2 — `loop-crossfade-ux` **Goal.** Give the loop an explicit enable, make the loop and crossfade marks legible, and paint the crossfade where it is actually heard. **Spec:** `docs/product/instrument-control-surface.md` §6 — **read §6.1 (the diagnosis), §6.4 (the enable) and §6.5 (trade-offs) in full before starting.** This is the phase's one genuinely designed surface; the sections are the brief. **Surface boundary — owns:** `shell/instrument/editor_paint_waveform.cpp`'s marker/loop draw, `shell/instrument/editor_input_waveform.cpp`'s marker hit-test routing, `core/instrument/ui/waveform_view` (cap rects, label boxes, the label-suppression rule — all pure, all CTest-covered), and — **new, from the Γ-F4 ruling** — `core/instrument/ui/sample_chrome` (the enable's rect in the toolbar control run), `shell/instrument/editor_paint_chrome` + `editor_input_chrome` (its draw and hit-test), and `shell/instrument/editor_session.cpp`'s **`pickedMarkers` / `applyMarkers` only** (the retention rule — see the wave header for the shared-file partition). **Does not own** `loop_span`, the crossfade model, any parameter, or any `ComponentState` version. **This track changes drawing, hit-testing and one editor-state retention rule — no format change.** **Behavior.** - **An explicit loop enable on the CHROME ROW (Γ-F4, ruled).** A two-segment `Loop Off|On` toggle joins the toolbar row's right-anchored control run, **immediately left of the `Mono|Stereo` toggle**, with Browse still rightmost. Loop is a waveform-overlay concept and **has no deck** — a deck cell was never the right home. Because the run is right-anchored and the title slot absorbs it, **this costs zero window width and none of the 90 px headroom**; if the title will not hold its text at the 1190 floor, **the enable's segments narrow — the floor does not move.** - **The enable IS `SampleLoop::hasLoop`. No new field, no version bump.** The field already exists (`play_params.h:210`), is already what `resolveLoop` refuses on (`loop_span.cpp:12`), and is already persisted in the payload's `loopOverride` block — where **`start`/`end` are written unconditionally whatever `hasLoop` says** (`params_payload.cpp:31-36`), so the wire can already carry "off, with a span remembered." What changes is the field's *provenance*: today it is derived from the marker gesture, and after this track it is **user-owned**, with the gestures as shortcuts onto it. - **Collapse-to-off survives as a shortcut, not as a second state machine.** `hasLoop` is the single authority; four gestures reach it: | Gesture | Enable | Span | Crossfade | |---|---|---|---| | Enable → On | on | retained | retained | | Enable → Off | off | **retained** | **retained** | | Collapse the span onto itself | off | **destroyed**, re-parked at `defaultLoopBounds` | **zeroed** | | Drag either loop mark while off | **on** | takes the drag | retained, re-clamped | - **Two consequent behaviour changes, each with its reason.** (a) `pickedMarkers`' re-park (`editor_session.cpp:221-226`) currently triggers on `!hasLoop`; it must become conditional on the span being **invalid** (collapsed / inverted / out of range) rather than on the enable being off — a toggle whose off→on does not restore what was there is a delete button, not a toggle. (b) `applyMarkers`' crossfade zeroing (`:240-243`) moves from "the enable is off" to "the span was destroyed." **The original reasoning is preserved, not overruled:** it zeroes so a stale length cannot silently re-apply against a span that no longer exists; with the span retained, its clamp bound is retained too and there is nothing stale. - **The "drag me" affordance splits into two off-states.** Off with **no span ever set** — pair parked at `defaultLoopBounds`, Disabled, caption `DRAG TO SET LOOP`. Off with a **span retained** — pair Disabled *at its own positions*, caption `LOOP OFF` (there is nothing to "set"). In both, **dragging a mark turns the enable on** — the shipped drag-to-create gesture survives and now teaches the enable by demonstration. - **In Trigger the enable draws Disabled and inert, and does NOT clear `hasLoop`** — Disabled-not-hidden, the same grammar as the marks, with its state restored on the return to Gate. This transitively covers the drawn-EG case via `enforceGateUnavailableWhileDrawn` (`play_params.h:198-205`), which forces Trigger whenever an envelope is drawn — one predicate, not a second rule. **Disabled-but-grabbable (the off marks) vs. Disabled-and-inert (Trigger) is deliberate:** the user's own off is reversible by the very gesture on offer; Trigger's refusal comes from the engine and no drag can talk it out of it. - **One mark grammar: line + shaped cap + label. The cap IS the grip.** Four marks: **START** (`accent/primary`, solid right-pointing triangle cap, solid line — the only primary-ink mark, because it is the only one always in effect); **LOOP** (`accent/secondary`, L-cap opening right); **END** (`accent/secondary`, L-cap opening left); **XFADE** (`accent/secondary` reduced alpha, ramp cap, **dashed** line — a soft boundary). This replaces the bare 10 px orphan tab that today marks the crossfade with no line of its own. - **Labels** in `Font::Micro`/`TextDim`, drawn **beneath** the trace and handles in z-order. A mark's label **re-draws on top on hover or drag** of that mark. **A label is suppressed if its box would overlap one already placed**; placement order is grabbed/hovered first, then START, LOOP, END, XFADE. Occlusion by an envelope node is **accepted and named** — the cap shape carries the identity permanently, the label is for learning. - **The crossfade moves to `[loopEnd − crossfade, loopEnd)`** — where it is audible. The handle moves to the loop-end side; **drag direction is unchanged** (left lengthens), so the muscle memory survives. - **The crossfade region draws as a top-and-bottom edge wedge, NEVER as a second fill.** A triangular band at the overlay's top and bottom edges growing from zero at `loopEnd − crossfade` to ~10 px at `loopEnd`. **This is a hard constraint:** the region is now *inside* the loop span, where a translucent fill would stack on the 0.20 loop fill, and the envelope trace crossing that fill is a known, accepted under-floor pair at 2.25:1 (`editor_paint_waveform.cpp:28-34`), whose own note says the FILL is what changes if it is ever resolved. **The loop fill's peak alpha must stay exactly 0.20.** - **The ingredient draws as a ghost.** `[loopStart − crossfade, loopStart)` draws the mirror wedge at half alpha, no handle — **a hairline dashed outline at rest, filling in on hover or drag of the crossfade handle**. This makes the `crossfade ≤ min(start, loopLength)` clamp self-explanatory: the fade stops growing exactly when the ghost's left edge reaches START or LOOP, so the user sees the reason instead of hitting an invisible wall. - **Trigger mode:** the loop pair and the crossfade mark draw **Disabled and are not grabbable**, with a dim `LOOP — GATE ONLY` caption — Disabled rather than hidden, matching the editor's existing Gate-segment grammar, and because hiding a set loop on a mode flip destroys information the user put there. START stays fully live. **Acceptance criteria.** - The four marks are distinguishable by ink and cap shape with the labels suppressed, and named when they are not. - **The shaded crossfade region sits over the frames where the fade is audible** — verify against a rendered loop, not by reading the code. - Every mark is grabbable by its cap; grabbing a mark shows its label. - The crossfade at its clamp shows the ghost's left edge coincident with the bounding mark. - **The loop fill's peak alpha is unchanged at 0.20** and the accepted 2.25:1 trace pair is neither improved nor worsened. - In Trigger, no loop mark accepts a grab, the chrome enable is Disabled and inert, and the reason is on screen. Returning to Gate restores the enable's prior state. - **Turning the enable off and on again restores the loop exactly** — same span, same crossfade, no re-park. Collapsing the span instead turns it off, re-parks at `defaultLoopBounds` and zeroes the crossfade. Both paths asserted. - **Dragging a loop mark while the enable is off turns it on**, in both off-states. - **The enable costs no window width:** `kEditorMinWidth` is unchanged by this track, asserted by the same derived test that guards the floor. - **No `ComponentState` version moves; no new persisted field; `resolveLoop` is untouched; audio is unchanged.** The enable round-trips save/reload through the existing `loopOverride` block, in both states, with the span retained across an off. - All cap/label/suppression geometry is pure and unit-tested; no hit-test math in the painter. The enable's rect lands in `sample_chrome` alongside the rest of the control run. **Open questions.** - **[propose at review, then verify by hand]** The claim-arbitration inputs change: `markerHandleRect` today gives a tab to the crossfade only, and `resolveWaveformClaim` breaks ties by smallest nominal target area. Giving every mark a cap-grip changes the candidate set **and every nominal area in it**. The arbitration must be re-derived, and `docs/TODO.md`'s open entry *"Pre-existing staged-envelope-node shadow at zero-attack"* must be **re-evaluated against the new cap geometry and its outcome recorded** — resolved or worsened, either is acceptable, silence is not. - **No [Daniel] questions.** Fork Γ-F4 is ruled — there **is** an explicit enable and it is on the chrome row, in this track. The prior framing ("an enable needs a cell, so it is a Γ-W3 layout decision") was wrong and is retired: loop has no deck, so it never needed one. - **[propose at review]** every site that currently *infers* `hasLoop` — two in `editor_input_waveform` (`:255`, `:258`), two in `editor_session` (`:222`, `:236`) — is now writing to a user-visible control rather than to an internal flag. Re-read each in that light; "it still compiles" is not a disposition. - **Named escalation, not a fallback to take silently:** if the top strip reads crowded in the DAW, the pre-designed answer is the marker rail (spec §6.2, Direction 2) — a larger build that would also dissolve the arbitration problem structurally. Escalate; do not improvise a half-rail. --- ### Γ-W3 — The reflow, and the bake correction **Depends on Γ-W2 for:** the PITCH/RATE descriptor (W2-T1) — the reflow measures the real three-cell group, and laying it out against a forecast of that group means re-measuring afterward. **This is the whole reason the arrangement is late**, and it is why the canvas was split out of it into W1-T4. **T2 depends on the same wave for a different reason:** rate and pitch offset must exist before the bake's reset list can name them. **Depends on Γ-W1 for:** W1-T2's published meter/GR/clip state, which MASTER's deck draws (drawing against a stub would mean building the meter twice), and W1-T4's floor, budget constants and row predicate, which T1 **consumes rather than re-derives**. **T2 depends on W1-T2 for the limiter enable flag**, the third of the three values it must add. **Depends on Phase Ξ for T2 — the phase's only EXTERNAL gate.** `Ξ-W2-T1 (resample-bake-chain)` must have landed on `dev` before T2 dispatches. T2 amends what that track shipped; it cannot amend a branch. **Two tracks, disjoint by surface — but T2's disjointness is CONDITIONAL and must be confirmed, not assumed.** T1 owns `ui/knob_deck`, `ui/deck_groups` (row-predicate consumption, FILTER's caption move, MASTER's inventory) and `shell/instrument/editor_paint_deck`. T2 owns the bake's reset step wherever Ξ-W2-T1 put it. **T2's first act is to read what actually shipped and confirm its reset surface touches none of T1's three modules.** If the shipped reset enumerates controls through `deck_groups` or `deck_values`, the two are not disjoint and **T2 serializes behind T1 inside the wave** — a named contingency, taken openly, not discovered at merge. That risk is real precisely because this plan cannot predict the shipped shape; predicting it is what put the phase in this position. **Why T1 is one track.** The row law, the group inventory and the double-height deck are one geometry decision spread over `knob_deck`, `deck_groups` and the deck painter. Splitting it would put two tracks in the same pure modules. **The window floor is no longer part of it** — W1-T4 set it two waves ago, and this track must not move it. **Neither track takes a payload rung.** T1 is layout only; T2 changes a reset list, not a format. #### Γ-W3-T1 — `deck-reflow` **Goal.** Two categorical rows plus a double-height MASTER bus deck, inside a 1280 × 720 ceiling, returning 112 px to the waveform. **Spec:** `docs/product/instrument-control-surface.md` §1 (the whole section, incl. the §1.2 measured table **and §1.6, the headroom ledger**) and §3.2–3.3 (what MASTER draws). **§7 lists the invariants this track invalidates or widens — read it before touching `knob_deck.h`.** **Surface boundary — owns:** `core/instrument/ui/knob_deck` (the row law, the double-height group, the justification — **consuming** W1-T4's budget constants, not restating them), `core/instrument/ui/deck_groups` (consumption of W1-T4's row predicate, FILTER's `Band|Notch` caption move, MASTER's inventory), and `shell/instrument/editor_paint_deck` (the MASTER meter/limiter/bubble draw). **Does not own** `kEditorMinWidth` or any budget constant — those are W1-T4's and are **read**, never moved — nor any parameter, the limiter DSP, or the waveform band. **Behavior.** - **Row 1 (sound), one row, non-negotiable:** PITCH/RATE 192 · FILTER 432 · VELOCITY 192 · VOICE 164 = **980** natural. - **Row 2 (contour):** PITCH ENV 252 · FILTER ENV 312 · AMP ENVELOPE 312 = **876** natural. - **MASTER is double-height (216 px) and right-anchored**, outside both rows, 142 px wide. - **FILTER's `Band|Notch` moves from its row-toggle position to the caption corner**, taking the group 524 → **432** (−92 px). It occupies FILTER's currently-unused `captionToggle2` slot — **no new geometry is required**. - **VOICE keeps its `Retrig|Legato` row toggle.** Moving it to the caption makes VOICE *wider* (226, not narrower), because its caption row is the binding side. Verified; do not "fix" it. - **Justification law, applied to BOTH rows:** space-between within the row block; slack divided equally among the row's (n−1) gutters, integer residue to the leftmost; **no gutter narrower than `kDeckGroupGap` (12)**. **Decks are never stretched.** MASTER is not part of either row's justification. - **Row block = 1020 px at the floor**, giving row 1 gutters 12/14/14 and row 2 gutters 72/72, at which width **FILTER's right edge and FILTER ENV's right edge both land on x = 636**. That tie-line, row 2's equal gutters, and row 1's minimum gutter being exactly `kDeckGroupGap` all hold at 1020 and only at 1020 — **this is why the floor is 1190 and not 1186.** Above the floor the tie-line drifts and that is accepted (spec §1.3). - **The floor is already 1190 × 680 and the bands are already 216 / 358** — Γ-W1-T4 landed all four in wave 1, and the greedy wrap happened to reach two rows at that width. **This track changes none of those numbers; it makes them true by construction instead of by coincidence.** Row 1's natural width fits the block **only after this track's `Band|Notch` move**: 1030 today, +42 from W2-T1's PITCH/RATE, −92 here, = **980**. That is this track's fit assertion and W1-T4 deliberately left it open. - **The 90 px of remaining headroom is the budget for the life of this layout**, and one deck cell is 60 px. **This is why MASTER's reserved slot is ONE cell** (Γ-F5, ruled): two would spend 60 of the 90 up front on a control nobody has named, leaving 30 — which would freeze row 1 forever, since any later row-1 addition needs 60. Widening MASTER later costs the same 60 it would cost now, and by then the trade is against a real control instead of a guess. **State this ledger where a future reader will hit it** — spec §1.6 is its home, and a reader proposing a new knob needs to see it before they propose. - **MASTER's interior** (spec §1.4, exact to the pixel): caption row with the limiter toggle and a **round** 12 px `warn` GR bubble in the far corner (non-interactive — the same slot the envelope decks' radio uses; round so it reads as a lamp, not a control); **gain knob in the upper-left cell at box-relative y = 26** and a **reserved empty slot at y = 138** — i.e. the two cells land on row 1's and row 2's knob baselines exactly, which is what stitches the spanning deck to both rows; **meter column 62 px wide × 186 px tall** on the right. - **Three rules not to generalise wrongly:** MASTER's left column uses **fixed cell slots at the two baselines, NOT the horizontal run-division law** (that law would stretch one knob over 186 px); the reserved slot **draws nothing** (blank reads as breathing room, a dashed placeholder reads as unfinished); the meter is **one rect spanning both baselines**, not two per-row meters. - **The meter draws W1-T2's published state**, with the ballistics run on the UI timer. **Bar count follows the same `LaneSplit` decision `waveformSurface` already folds** (channel mode ∧ source channel count) — one wide bar when the waveform draws one lane, two skinnier bars when it draws two. Not a second rule: a mono source in stereo mode is dual-mono, and two identical bars would be a lie. - **Meter appearance:** bar in `accent/primary`; peak-hold tick 2 px in `text/primary`; clip cap in `warn`, latched, click-to-clear; scale linear in dB over −60…+6 with ticks every 6 dB and numerals at 0/−12/−24/−36/−48/−60, the 0 dB tick heavier. **No green/yellow/red segmentation** — `warn` stays reserved for clip states. **Acceptance criteria.** - At the floor width the deck lays out in **exactly two rows plus the spanning MASTER**, **by construction** — asserted against the group inventory, not observed as a wrap outcome. - Every group's width matches the §1.2 table exactly, **in both Gate and Trigger** (row 2's natural width is mode-stable at 876 because the reserve slots hold FILTER ENV and AMP at 312 in both modes — assert it). - Row 1 and row 2 are **flush left and flush right**; at the floor width the filter tie-line is exact (both edges at x = 636) and row 2's two gutters are equal. - **Row 1's natural width is 980 and fits the 1020 block** — the fit Γ-W1-T4 could not yet assert, closed here by the `Band|Notch` move. - **`kEditorMinWidth` is still 1190 and the floor is still ≤ 1280 × 720** — unchanged by this track, verified against Γ-W1-T4's derived test rather than a second copy of it. - The waveform band is **358 px at the floor**, and the deck band is 216 — **unchanged from the interim, now reached by construction**: `deckRowCount` at and above the floor is 2 because the row predicate says so, not because a wrap landed there. Assert against the group inventory. - MASTER's gain knob shares a knob baseline with FILTER's knobs; its reserved slot shares one with AMP ENVELOPE's. - The meter reads correctly in mono and stereo, the peak-hold tick holds 1.5 s, the clip cap latches and clears, and the GR bubble lights only while the limiter reduces gain. - **With the limiter engaged the clip cap never latches** on material the limiter is catching; if it does, that is a defect report against W1-T2, not a user error. - `knob_deck`'s and `sample_bands`' tests are updated to the new law, and the invalidated notes in `knob_deck.h` (the fourteen-pixel headroom figure; the cells-and-floor pairing) are **re-derived, not deleted** — spec §7.1, §7.4. **Open questions.** - **[propose at review]** Whether the greedy whole-group wrap survives at all as a sub-floor degrade, or is replaced outright by explicit row assignment. What is **not** optional: at and above the floor width the layout is the specified arrangement, reached by construction. `DeckLayout::rowCount`/`::height` change meaning either way (spec §7.3). - **No [Daniel] questions.** Forks Γ-F5 (**one cell**) and Γ-F1 (**680 stays**) are both ruled; they are stated in Behavior above, not carried here as options. - **[verify]** `deck_groups.cpp`'s `kEnvModeSegW = 23` ceiling rises to **47** once PITCH ENV is on row 2 (AMP binds at 55). No change is required; the comment stating the old ceiling stops being true and must be corrected (spec §7.2). #### Γ-W3-T2 — `bake-reset-amendment` **Goal.** Complete the resample bake's reset list against the control surface that now exists — the correction Phase Γ owes Phase Ξ because Ξ-W2-T1 shipped ahead of the sequencing this plan asserted. **Consolidates:** nothing from the seventeen. It is a **correction obligation**, not a feature (see "Flagged for awareness" item 2). **Spec:** `docs/product/instrument-control-surface.md` §3.4, and Ξ-W2-T1's own "Reset scope" block above — **which is the ratified rule this track applies, not a rule it may reinterpret.** **Surface boundary — owns:** the bake's parameter-reset step, wherever Ξ-W2-T1 landed it, and its tests. **Does not own** the bake chain, the crossing architecture, the replace-vs-add decision, the capture path, any deck module, any painter, any parameter, or any `ComponentState` version. **It changes what a shipped list contains — nothing else.** **Behavior.** - **Three values join the reset list**, all classified against Ξ-W2's own ratified rule ("reset what the bake baked in"), all **reset**, none of them a new Daniel decision: **rate**, **pitch offset**, and **limiter enabled**. The limiter's reasoning is worth carrying rather than re-deriving: master gain is already on the reset list, so the bake includes the master stage, so the limiter's effect is in the audio. - **Verified against what shipped, not against what was predicted.** This plan named three values before either the bake or the controls existed. **Read Ξ-W2-T1's landed reset list first** and reconcile: if it already anticipated any of the three, say so and drop it; if it classified something differently from `docs/product/instrument-control-surface.md` §3.4, **the landed code is the fact and this plan is the prediction** — escalate the difference, do not silently overwrite either. - **Re-run Ξ-W2-T1's own "genuinely new parameter" check over everything Phase Γ added**, not just the three named. Γ also ships the loop enable (W2-T2) and raises the stage-time ceiling (W1-T1). Classify each **against the rule**: the loop enable is a loop fact whose effect is in the rendered audio (**reset**, with the loop points it travels with); the ceiling is not a parameter at all. State each disposition; silence is not one. - **Root note still survives.** The bake's most load-bearing exception is untouched by this track — capturing at root is what makes root survivable, and resetting it would detune every subsequent iteration. **Acceptance criteria.** - After a bake, **rate reads 100 %, pitch offset 0 st, and the limiter reads bypassed** — and the root note, key-tracking and the VOICE group are still untouched. - **The bake stays audible and faithful with the new controls dialled in**: dial rate, pitch offset and the limiter, bake, and the neutral instrument playing the programmed note sounds as the dialled one did — the criterion Ξ-W2-T1 already carries, now actually exercised over Γ's controls. - **A reconciliation note in the track's review** stating, per value, whether the landed code already covered it, and recording any difference between what shipped and what §3.4 predicted. - **No format change, no new field, no version bump, no change to the crossing architecture or the replace-vs-add decision.** A regression baseline proves the bake's audio is otherwise unchanged. **Open questions.** - **No [Daniel] questions.** The rule is ratified and §3.4's classification is derived from it. - **[verify, FIRST]** the disjointness contingency in the wave header: read the shipped reset step and confirm it touches none of Γ-W3-T1's modules. If it does, serialize behind T1 and say so. - **Explicitly NOT this track's:** the two consequences automation adds to the bake — the reset having to notify the host, and a host lane re-imposing its curve onto baked audio. Both are **Γ-W4-T1's**, because that track creates them. Doing this correction once, before automation, and letting Γ-W4-T1 add its own obligation on top is deliberate: the alternative is an amendment to an amendment. --- ### Γ-W4 — VST3 parameters **Depends on every earlier wave, and each dependency is a hard prerequisite rather than a courtesy:** 1. **← W1-T1.** The taper and the 10 s ceiling **are** the host-facing normalization, and W1-T1 is also what extracts them into the one pure module the host reads through. Declaring parameters against a taper that is still moving is the one-way door this whole phase is ordered around. 2. **← W1-T2 and W2-T1.** Every control that could be a parameter must exist before the list is declared. The list is derived from the control inventory; an inventory still growing produces a list that has to be re-frozen, and it cannot be. 3. **← W2-T1 specifically.** `isLiveDeckParam` becoming three-valued is the *prerequisite* of the classification, not an incidental: the exposed set is exactly `Live ∪ NoteOnLatched`. 4. **← W3-T1.** MASTER's inventory (limiter toggle, GR bubble, reserved cell) is the last change to what controls exist at all. 5. **← W3-T2.** The bake's reset list must already be complete, so this track adds the host-notification obligation once rather than amending an amendment. **One track.** The storage decision governs every part of the work — the projection rule, the migration path, what `getParamNormalized` returns, and what the bake's reset must do — exactly as Ξ-W2-T1's crossing decision governs its chain. Every candidate split (a pure model/classification half and a host-wiring half) is **serial**, so it buys no concurrency and puts the decision on one side of a boundary and its consequences on the other. #### Γ-W4-T1 — `vst3-parameter-set` **Goal.** The instrument reports its automatable parameters to the host, under a frozen id contract and a logical order — which also hands it REAPER's whole per-parameter modulation block (LFO, envelope follower, MIDI link, parameter linking) for free. **Consolidates:** nothing from the seventeen. **Ruling 1** (Daniel, 2026-08-01): *"correct the phase gamma plan to account for complying with the VST3 standard for parameter reporting… by the end of gamma we have the automatable params reported. Make the parameter order logical."* **Spec:** `docs/product/parameter-automation.md` — **§§6–10 are the specification; §§1–5 are the analysis behind it.** Read §6.1 (storage), §6.3 (the freeze), §7 (the classification) and §8 (the one-way-door sweep) before scoping. **Today the plugin has zero parameters:** `ReaSamplerProcessor::initialize` (`reasampler_processor.cpp:56-73`) never populates `SingleComponentEffect::parameters`, so `getParameterCount()` returns the SDK default 0. This track introduces the whole surface. **Surface boundary — owns:** a **new pure parameter-identity module** (the frozen id table, the `DeckParam` ↔ `ParamID` mapping, the derived exposed set, the unit assignment — with its own `_tests` target), `shell/instrument/reasampler_processor` + `processor_state` (the `IEditController` parameter surface and the `IParameterChanges` read), `shell/instrument/editor_controls.cpp` and the editor's drag-commit sites (the `beginEdit`/`performEdit`/`endEdit` bracketing), and the bake's reset step **for the notification path only**. **Does not own** the taper (W1-T1's module, consumed), any control's value semantics, any deck geometry, or the bake's reset *membership* (W3-T2's). **Behavior.** - **The blob stays authoritative; a parameter is a THIRD SURFACE onto the one model** — a peer of the deck knob and the overlay node, not a second copy of the value. `docs/product/parameter-automation.md` §6.1 states the load, host→plugin, plugin→host and save rules, and the two verified findings that closed the fork: this plugin is a `SingleComponentEffect`, where the SDK itself collapses `IComponent::setState` and `IEditController::setState` (`vstsinglecomponenteffect.h:41-47`), so there is one state and §3.3's drift hazard describes a split-component design we do not use; and the blob is a **cross-artifact contract** the extension's `instrument_drop` writes, which parameters-as-truth would silently make partial. - **`ParamID` is an independent, hand-assigned, FOREVER-FROZEN table** — blocks of 100 per deck group, steps of 10 within a block, a curve dial at its outer knob's id + 1, blocks starting at 1000. §6.2 for the layout and why hand-assignment beats derivation; **§6.3 for the freeze invariant, which is to be stated in the table's header with the same force as the command-id strings, the class UIDs and the payload field order.** - **The exposed set is DERIVED from `isLiveDeckParam` / `liveCommitFor`, never hand-maintained** — a control is a parameter iff its class is `Live` or `NoteOnLatched`. **44 parameters** at the end of Γ-W3, enumerated by group in §7.1. - **Everything else is OMITTED from the list entirely**, not exposed-and-flagged: the reload and rebuild tiers, all structural state, and the limiter enable (§3.8, settled). §7.2 states why omission beats `kIsReadOnly`, and names the limitation plainly — the user cannot automate filter on/off, play mode, the pitch engine, Staged↔Spline or polyphony, and the unlock is to give the control a live path first. - **`normalizedParamToPlain` / `plainParamToNormalized` / `getParamStringByValue` / `getParamValueByString` route through W1-T1's taper module and the editor's own formatters.** Three functions that agree today is a defect; the host's normalization, the needle angle and the overlay node must be the same function. - **`IParameterChanges` is observed at BLOCK boundaries, stated in the header** — the last point in a block wins. Sample-accurate application would put a per-sample "did anything change" question on the per-voice-per-sample path, which the phase-wide guardrail forbids. - **A host parameter change takes the control's existing commit tier and no other.** Nothing on the automation path may reach `reloadInstrument` or `rebuildVoiceEngine` — which §7.2's omissions guarantee structurally rather than by care. - **`IUnitInfo`: one unit per deck group.** Order per **Γ-F7** (§6.4) — **recommendation signal flow; Daniel's call, and it must be closed before this track dispatches.** - **No `kIsBypass` on anything.** The plugin is an instrument and exposes no bypass parameter; the limiter is a safety device, not a bypass, and binding it there would hand the host a control that restarts the component. - **The bake's reset gains a notification obligation** (§9): every internal writer of a value that is an exposed parameter must go through the one `beginEdit`/`performEdit`/`endEdit` path, and the bake's reset is the codebase's first non-gesture writer. **Enumerating those sites is part of this track**, not a follow-up. - **Two adjacent SDK surfaces are assessed, with dispositions, so they are not re-surveyed:** `IMidiMapping` is **in scope and nearly free** (a CC → `ParamID` map, one function); `IParameterFunctionName` is **not implemented** (its vocabulary is compressor/panner semantics that name nothing here); `IAutomationState` is **not implemented** (it reports the host's automation mode for the whole plug-in, not per parameter, so it cannot answer the one question §9 would have wanted it for). **Acceptance criteria.** - **The host lists exactly the derived set, in the ruled order, with no parameter the predicate does not classify `Live` or `NoteOnLatched`** — asserted against the predicate, not against a literal count. - **Every id in the table is asserted unique, in its group's block, and on its step** — and a test fails if any id changes value, which is what makes the freeze mechanical rather than cultural. - **Every parameter round-trips `plain → normalized → plain` exactly at its default**, so a host's reset-to-default and the editor's double-click land on the same value. If this fails, it is a W1-T1 defect surfacing here, not a defect of this track. - **`getParamStringByValue` prints what the editor prints**, unit for unit, at the same values. - **A host automation lane moving a Live parameter moves a sounding note; a lane moving a NoteOnLatched parameter takes effect on the next note and does NOT trigger a reload or an engine rebuild** — assert the tier, not just the sound. - **No automation path reaches `reloadInstrument` or `rebuildVoiceEngine`.** - **A project saved before this change opens with every parameter reading the blob's value and sounds identical**; a project saved by this build opens in an older binary with its sound intact; and a project with automation drawn, saved and reopened, replays against the same plain values. - **`process()` takes no new indirection and no new per-sample work** — the parameter read is a block-boundary act, on the existing live-publish path. - **The bake's reset notifies the host**, verified by the host's displayed value following it rather than snapping back on next touch. - **The double-processing limitation is documented, not discovered** — a bake whose reset-class parameter carries a host lane is a named boundary of the bake's fidelity claim (§9), stated in the product doc and in this track's review. **Open questions.** - **[Daniel] — Γ-F7, the parameter order.** Signal flow (recommended) or the editor's visual rows. **This is the only unanswered [Daniel]-class question in this plan.** It blocks nothing until this track dispatches, and it cannot be closed by proposal at review: a forever commitment is Daniel's. §6.4. - **[verify, FIRST]** that REAPER calls `setState` (not `setComponentState`) on a single-component plug-in, and the ordering of `setState` against the first `IParameterChanges` block after a project load. §6.1 is built on the SDK's own name-collapse; **verify it in the DAW before wiring, and do not build on the paragraph alone.** - **[propose at review]** promoting **key-track** and **Trigger length** from `Reload` to `NoteOnLatched` (§7.4). Both are excluded from the live set *for the note-on-latch reason* in the predicate's own words, so the promotion aligns routing with documented semantics — and it is what makes them automatable at all. **If either promotion is refused, that control simply drops out of the parameter list.** The list follows the predicate; the predicate is never bent to fill the list. - **[propose at review]** whether to ship a default `IMidiMapping` CC table here or leave MIDI control to REAPER's host-side learn. Either is defensible; **skipping it silently is not.** - **[propose at review]** whether this track spends the reserved payload rung. §6.1 says nothing new is persisted and therefore it should not; if the `setState` verification says otherwise, it takes the reserved rung and says so. - **Closed, do not reopen:** Rate lifted from latched to live (§3.5 records the cost); the limiter enable made automatable (§3.8 — its one reopening condition is the `docs/TODO.md` reload/activation decoupling, and the answer is to do that first, not to re-litigate the classification). --- ## Traceability — all seventeen items The check that nothing was dropped. Every row points at a track that exists above. | # | Item (short) | Phase-Wave-Track | Worktree slug | |---|---|---|---| | 1 | Envelope editor: radio switch, curve dials, overlay recolor | Θ-W3-T2 | `pth-w3-t2-staged-envelope-curves` | | 2 | MM preamp Filter — resonant HP/LP stage | Θ-W1-T3 (DSP) **+** Θ-W2-T1 (integration) | `pth-w1-t3-filter-dsp-port`, `pth-w2-t1-filter-voice-path` | | 3 | Alternative Spline EGs | Θ-W5-T1 | `pth-w5-t1-spline-egs` | | 4 | Bug: end-of-sample click, Trigger × Preserve | Θ-W3-T2 | `pth-w3-t2-staged-envelope-curves` | | 5 | Bug: drag-out sometimes lands without audio | Θ-W1-T2 | `pth-w1-t2-capture-handoff-bugs` | | 6 | Bug: FX-container drop loses the capture | Θ-W1-T2 | `pth-w1-t2-capture-handoff-bugs` | | 7 | Stereo waveform shows both channels | Θ-W2-T2 | `pth-w2-t2-stereo-waveform-lanes` | | 8 | Release anchoring; the Pitch AD becomes AHD | Θ-W3-T2 | `pth-w3-t2-staged-envelope-curves` | | 9 | Loop points — regression + Gate loop-sustain | Θ-W4-T1 | `pth-w4-t1-gate-loop-sustain` | | 10 | Knob/label sizing, ms units, double-click reset | Θ-W6-T1 | `pth-w6-t1-legibility-and-antialiasing` | | 11 | Preview glyph; VELOCITY deck; bipolar curves | Θ-W4-T2 | `pth-w4-t2-velocity-deck-and-bipolar-curves` | | 12 | Toolbar cleanup; full-width piano strip; tooltips | Θ-W2-T3 | `pth-w2-t3-toolbar-and-piano-strip` | | 13 | Antialiased rendering audit for high-DPI | Θ-W6-T1 | `pth-w6-t1-legibility-and-antialiasing` | | 14 | Trigger amp/filter fade → AHD consolidation | Θ-W3-T2 | `pth-w3-t2-staged-envelope-curves` | | 15 | One-click in-sampler resample | Ξ-W1-T2 (note model) **+** Ξ-W2-T1 (bake chain) **+** Ξ-W3-T1 (popup) | `pxi-w1-t2-note-program-model`, `pxi-w2-t1-resample-bake-chain`, `pxi-w3-t1-capture-signal-popup` | | 16 | Retire the zone mapping system | Θ-W1-T1 | `pth-w1-t1-zone-retirement` | | 17 | Consolidate provenance/usage tracking | Ξ-W1-T1 | `pxi-w1-t1-tracking-consolidation` | ### Work in this plan that is not one of the seventeen The table above is a completeness proof over `TODO-1.0.md` — every row points at a track, so nothing from the source was dropped. It is deliberately **not** an index of the plan: work that did not come from the source doc has no row, and inventing one would weaken the proof it exists to give. - **Θ-W3-T1 — `live-parameter-delivery`** (`pth-w3-t1-live-parameter-delivery`). Arose from Θ-W2-T1's implementation review, not from `TODO-1.0.md`. The first such track in this plan; see Θ-W7-T1 below for the second. - **Θ-W7-T1 — `arc-and-spline-aa`** (`pth-w7-t1-arc-and-spline-aa`). Opened after Θ-W6-T1 shipped, when Daniel found two rendering defects by eye in the editor — not from `TODO-1.0.md`, and not a track this plan originally scoped. The second such track in this plan today; if others appear, they belong on this list rather than in the table. - **All of Phase Γ** (`pg-*`). **Ten tracks across four waves**, from a direct interview with Daniel (2026-08-01) and his four later rulings the same day, not from `TODO-1.0.md`. Listed here as a block rather than per track, because the whole phase is outside the source doc; the product reasoning lives in `docs/product/instrument-control-surface.md` and the parameter system's in `docs/product/parameter-automation.md` §§6–10. **Two `docs/TODO.md` entries are discharged by this phase, not deferred again:** Γ-W3-T1 discharges the deck-rework entry (whose original "one row of taller decks with within-deck stacking" shape Daniel explicitly superseded), and **Γ-W1-T1 discharges "Raise the stage-time ceiling above 2 s"** (Γ-F3 reversed). - **Γ-W3-T2 `bake-reset-amendment` is a CORRECTION, not a feature**, and belongs on this list for a different reason from the others: it exists only because Ξ-W2-T1 shipped ahead of this plan's sequencing claim. If more corrections of this shape appear, they belong here rather than in the table — the table is a completeness proof over `TODO-1.0.md`, and a correction has no source row to point at. ### Deliberate compressions Recorded so a reader of `TODO-1.0.md` can see what this plan did to the source, rather than discovering it later: - **Item 2 is split across two waves.** The DSP port (Θ-W1-T3) is deliberately separated from the integration (Θ-W2-T1) so the external-input dependency on Daniel's Cortex-M4 code sits on a standalone, disjoint track instead of blocking a wave. Item 2's acceptance criteria are split accordingly — the range/resonance assertions land in W1-T3's tests, the audible/pipeline/deck criteria in W2-T1. - **Item 2's filter envelope ships twice.** W2-T1 ships it in the existing staged AHDSR shape; W3-T2 gives it the curve treatment and the mode-driven Gate→AHDSR / Trigger→AHD shape. This is deliberate: waiting would put the filter behind the whole envelope system. - **Item 4 lands in Θ-W3, not Θ-W1.** Its fix region is the region item 14 retires, and the only earlier instrument-side track owns the entire engine. Its acceptance gate is stated as the post-consolidation gate. It is not gated behind the *whole* editor chain — three waves of six — and the source doc itself requires re-verification under the surviving mechanism either way. - **Item 11's filter velocity curve is split from item 2's filter velocity modulation.** W2-T1 wires the modulation path (following the amp/pitch precedents); W4-T2 sets the curve's bipolar domain and default and homes its button. Neither track can do the other's half. - **Item 15's undo/recovery is carried as a note, not a criterion** — Daniel set it at exactly "a plus." The guaranteed recovery floor (the superseded file surviving until prune) is a criterion. - **Nothing else was compressed.** Every other item's behavior bullets and acceptance criteria are carried at full strength into the track that owns it. --- ## Outline at a glance ``` Phase Θ — ReaSampler 9000: one parameter set, filter, shapeable envelopes, legible editor W1 Collapse and re-seam T1 zone-retirement ......................... 16 T2 capture-handoff-bugs .................... 5, 6 T3 filter-dsp-port ......................... 2 (DSP) [needs Daniel's M4 code] W2 Filter in the voice path; waveform and chrome bands T1 filter-voice-path ....................... 2 (integration) T2 stereo-waveform-lanes ................... 7 T3 toolbar-and-piano-strip ................. 12 W3 Live parameters, then the staged envelope system [T1 before T2 — serial] T1 live-parameter-delivery ................. (not one of the seventeen) T2 staged-envelope-curves .................. 1, 8, 14, 4 W4 Loop sustain and the velocity deck T1 gate-loop-sustain ....................... 9 T2 velocity-deck-and-bipolar-curves ........ 11 W5 Spline EGs T1 spline-egs .............................. 3 W6 Editor legibility pass T1 legibility-and-antialiasing ............. 10, 13 W7 Arc-and-spline antialiasing fix T1 arc-and-spline-aa ....................... (not one of the seventeen) Phase Ξ — The resample loop (W1 concurrency-safe with Θ from Θ-W2 onward) W1 Consolidated tracking, and the programmed-note model T1 tracking-consolidation .................. 17 T2 note-program-model ...................... 15 (model) W2 The bake chain [ran AHEAD of Γ; its reset list is corrected by Γ-W3-T2] T1 resample-bake-chain ..................... 15 (chain) W3 The capture-signal popup T1 capture-signal-popup .................... 15 (popup) Phase Γ — The instrument's control surface (none of the seventeen; ends with VST3 params) W1 Foundations [5 tracks, disjoint by surface] T1 knob-interaction-law ....... modifiers + ONE taper module + reset bypass + 10 s ceiling + AHDSR schematic axis [Ruling 2] T2 master-bus-audio ........... limiter + meter ballistics + dynamic PDC [rung 1] T3 contour-trace-curves ....... staged traces draw curved, knot on its trace T4 editor-floor-and-row-law ... floor 1190x680 + budget constants + row predicate T5 preserve-time-stretch ...... real stretcher [measure-and-report gate] W2 New controls, and the overlay's marks [2 tracks] T1 pitch-rate-deck ............ Rate + Pitch, Varisp/Presrv compounding [rung 2] T2 loop-crossfade-ux .......... four-mark grammar; fade painted where it is heard W3 The reflow, and the bake correction [2 tracks] T1 deck-reflow ................ two rows + double-height MASTER, by construction T2 bake-reset-amendment ....... the Xi correction Gamma owns [needs Xi-W2-T1 on dev] W4 VST3 parameters [1 track] T1 vst3-parameter-set ......... 44 derived params, frozen id table [Ruling 1] [rung 3 RESERVED, spent only if verify says so] [OPEN: Gamma-F7, the parameter order — Daniel] Resequenced 2026-08-01, three times: the reflow split canvas (W1-T4) from arrangement (W3-T1); preserve-time-stretch moved W4 -> W1-T5, retiring Rate's interim stand-in; then Ruling 1 added W4 and Ruling 2 grew W1-T1. Payload rungs are RELATIVE, not absolute — read kParamsPayloadVersion on dev and take the next three above it. On dev at 2026-08-01 that is v14 / v15 / v16-reserved. Shared files, named: engine/CMakeLists.txt (W1-T2 | W1-T5), ui/CMakeLists.txt (W1-T1 | W1-T3), editor_session.cpp (W2-T1 | W2-T2) — all textual adjacency, not semantic contention. W3-T2's disjointness from W3-T1 is CONDITIONAL: confirm it against what Xi-W2-T1 shipped, and serialize behind T1 if it does not hold. ```