instrument: spline EGs — hard points on the one shared spline, a drawn contour per envelope beside its staged state, payload v13

src/shell/instrument/reasampler_editor.h

@@ -20,6 +20,7 @@
 #include "core/instrument/ui/envelope_overlay.h" // StageEnvelope / EnvNode (envelope overlay draw seam)
 #include "core/instrument/ui/knob_deck.h"        // DeckGroupDesc / DeckLayout (the deck band)
 #include "core/instrument/ui/sample_bands.h"     // SampleBands (the band-stack allocator)
+#include "core/instrument/ui/spline_edit.h"      // the shared point-editing grammar
 #include "core/instrument/ui/sample_chrome.h"    // ChromeRects (chrome-band interior)
 #include "core/audio/peaks.h"            // Envelope (the cached peak thumbnail)
 #include "core/instrument/map/sample_map.h"       // SampleChoice, BankChoice, InstrumentParams
@@ -78,8 +79,11 @@ private:
     // What a mouse drag is currently editing. kWaveMarker/kEnvNode/kCurveNode track their
     // grabbed item in waveMarker_/envNode_/curvePointIndex_; kDeckKnob is a grab-anchored
     // knob drag (control in dragParamId_, grab value in dragKnobStartValue_).
+    // kSplineNode is the overlay's peer of kCurveNode: the same VelocityCurve point drag, over
+    // the waveform overlay's box and the overlay-active envelope's contour rather than the
+    // popup's box and curve.
     enum class DragKind { kNone, kRootMarker, kWaveMarker, kScrollThumb, kEnvNode,
-                          kCurveNode, kDeckKnob };
+                          kCurveNode, kSplineNode, kDeckKnob };
 
     // Which envelope the waveform overlay is drawing and editing. The selection type and its
     // whole state machine are the pure deck_groups module's; this alias keeps the shell's
@@ -168,9 +172,20 @@ private:
     // The velocity transfer-curve editor (X = velocity 0-127, Y = the curve's own domain); its
     // only host is the popup sheet. `r` empty -> draws nothing.
     void paintVelocityCurve(LICE_IBitmap* bmp, const Rect& r);
-    // Traces the amp-envelope overlay + its draggable node handles over `waveArea`, ONCE at
-    // full band height (never per lane).
+    // Traces the overlay-active envelope + its draggable handles over `waveArea`, ONCE at
+    // full band height (never per lane). Dispatches on the envelope's mode: the staged
+    // polyline, or the drawn contour below.
     void paintEnvelopeOverlay(LICE_IBitmap* bmp, const OverlayArea& waveArea, std::int64_t frames);
+    // The spline EG's contour + point handles, spanning the overlay 1:1 with the sample's time
+    // axis. Hard points draw hollow so a corner is legible before it is steep.
+    void paintSplineOverlay(LICE_IBitmap* bmp, const OverlayArea& waveArea);
+
+    // A click on the spline overlay, routed through the shared grammar; true when it consumed
+    // the click. `addOnEmptySpace` false resolves node actions only — the waveform band calls
+    // it that way BEFORE the start/loop markers and again after, since the contour's box is the
+    // whole band and an unconditional add would make every marker unreachable.
+    bool splineOverlayClick(const OverlayArea& waveArea, int x, int y,
+                            instrument::ui::SplineGesture gesture, bool addOnEmptySpace);
 
     // --- Input: the mouse-down dispatch and its per-band branches ---
     void onMouseDown(int x, int y);
@@ -194,13 +209,15 @@ private:
 
     void onMouseMove(int x, int y);
     void onMouseUp(int x, int y);
-    // Right-click is the curve popup's primary node-delete affordance; only acts while the
-    // popup is open (deletePoint's endpoint guard makes an endpoint right-click a no-op).
+    // Right-click is the primary node-delete affordance on both spline surfaces — the popup
+    // while it is open, else the spline EG overlay (deletePoint's endpoint guard makes an
+    // endpoint right-click a no-op).
     void onMouseRDown(int x, int y);
 
-    // Mouse-down inside curve-editor box `r`: a node grab starts a kCurveNode drag;
-    // Alt-click on an interior node deletes it at once; an empty-space click adds a point
-    // and grabs it.
+    // Mouse-down inside curve-editor box `r`, resolved through the shared point-editing
+    // grammar (spline_edit): a node grab starts a kCurveNode drag, an empty-space click adds a
+    // point and grabs it, control-click toggles a node hard/smooth. Alt-click delete predates
+    // that grammar and is kept as a landed alternate.
     void handleCurveMouseDown(const Rect& r, int x, int y);
 
     // Left-click while the curve popup is open (modal over the Sample face): Close /
@@ -466,6 +483,20 @@ private:
     CurveTarget curvePopup_ = CurveTarget::kNone;
     void closeCurvePopup();
 
+    // The group-gate state the two pure inert predicates read, built once from the parameter
+    // set so paint and hit-test can never assemble it differently.
+    instrument::ui::DeckEnableState deckEnableState() const;
+
+    // THE one switch from an overlay selection to the drawn contour it names, mirroring
+    // curveFor. kNone reads as amp — harmless for a target-agnostic caller, and every mutating
+    // path is gated on overlayIsSpline() first.
+    const VelocityCurve& splineFor(OverlayEnv which) const;
+    VelocityCurve& splineFor(OverlayEnv which);
+
+    // Whether the overlay-active envelope is in Spline mode — the branch every overlay paint,
+    // hit-test and drag path takes before touching either model.
+    bool overlayIsSpline() const;
+
     // THE one switch from a CurveTarget to the parameter-set curve it names — paint (button
     // thumbnails, for every target) and edit (editedCurve, for curvePopup_ specifically) both
     // route through it, so a fourth curve or a moved field is a one-place edit.