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.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.