Bake window derives itself: %-knob fold, declick pad, Gate held to exhaustion, preview velocity; Hold is the one knob a loop needs

src/core/instrument/engine/voice.cpp

@@ -6,6 +6,8 @@
 
 #include <algorithm>
 
+#include "core/instrument/map/trigger_seam.h"  // effectiveLengthFraction (the one %-length rule)
+
 namespace reasampler {
 
 void Voice::presizePreserveShifters(std::int64_t windowFrames) {
@@ -101,13 +103,11 @@ void Voice::start(int note, int velocity, const SampleData& sample, bool declick
         env_.noteOn();
         playEnd_ = 0;  // unused in Gate
     } else {
-        // Trigger: play [start, playEnd) where
-        // playEnd = start + round(lengthFraction*(frames-start)) — except kTrigLength is INERT
-        // while any spline EG is active (splineActive, play_params.h): a contour is a pure
-        // function over the FULL sample length, so truncating playEnd_ to a %-length would
-        // hard-cut it mid-shape. The staged Trigger AHD below (trigSpan) plays the same full
-        // span in that case, matching the "drawn-but-dead" treatment of the other staged knobs.
-        double frac = splineActive(p) ? 1.0 : p.trigger.lengthFraction;
+        // Trigger: play [start, playEnd) where playEnd = start + round(frac*(frames-start)).
+        // The spline fold lives in effectiveLengthFraction (trigger_seam.h), which the bake's
+        // window derivation reads too — a second copy of it here is what let a stored-but-inert
+        // %-knob shorten the bake while the voice played the whole take.
+        double frac = instrument::map::effectiveLengthFraction(p);
         if (frac <= 0.0) frac = 0.0;      // %=0 -> zero play length (finishes immediately)
         if (frac > 1.0) frac = 1.0;
         std::int64_t playLen = static_cast<std::int64_t>(

src/core/instrument/engine/voice.h

@@ -81,6 +81,17 @@ inline double filterNormPerOctave() {
 inline constexpr double kDeclickDecay = 0.95;  // per-frame decay of the compensation
 inline constexpr double kDeclickFloor = 1e-4;  // below this the ramp is done (~ -80 dB)
 
+// How many frames the ramp emits before the weight drops under the floor. Counted the way
+// advanceFrame runs it — emit, decay, test — rather than solved in closed form, so the two
+// can never disagree. RATE-INDEPENDENT: the decay is per frame, not per second, so an offline
+// pass at any rate pads by the same count.
+inline constexpr std::int64_t declickRampFrames() {
+    std::int64_t n = 0;
+    for (double w = 1.0; w >= kDeclickFloor; w *= kDeclickDecay) ++n;
+    return n;
+}
+inline constexpr std::int64_t kDeclickFrames = declickRampFrames();
+
 // A single voice: one active note playing the loaded capture, repitched and enveloped.
 // Reads the sample by fractional frame position with linear interpolation, advancing by the
 // pitch ratio; loops the sustain region for held notes past the loop end.