Bake window: derived note lengths carry exact durations, not ladder rungs — a long take is no longer cut at 384 beats

Hold keeps its picker. Also: one home for the %-fold, duration-ordered Hold travel, and a corrupt tail degrades to absent rather than fabricating one.

tests/test_trigger_seam.cpp

@@ -2,13 +2,16 @@
 // Same fast assert loop as the sibling pure tests.
 //
 // Covers triggerPlayLength: zero play length, startFrame set, startFrame past frameCount,
-// rounding, and the Finding 1 regression (start-point set — the case that was broken before
-// this module existed); plus effectiveLengthFraction, the spline fold every consumer of the
-// span must go through.
+// rounding, the out-of-domain clamps that keep it identical to Voice::start's inline copy of
+// the same formula, and the Finding 1 regression (start-point set — the case that was broken
+// before this module existed). The spline fold that used to live here is now beside its
+// siblings in play_params.h, and pinned with them in test_spline_egs.
 
 #include "../src/core/instrument/map/trigger_seam.h"
 
+#include <cmath>
 #include <cstdio>
+#include <limits>
 
 using namespace reasampler;
 using namespace reasampler::instrument::map;
@@ -58,46 +61,19 @@ static void testPlayLengthRounding() {
     CHECK(triggerPlayLength(0.6, 3, 0) == 2);
 }
 
-// --- effectiveLengthFraction --------------------------------------------------
-
-// A drawn contour covers the FULL sample length, so the stored %-knob goes inert. It is not
-// cleared, though — a pre-spline value survives in the record, and every reader that takes it
-// raw plays, draws or bakes a fraction of the take.
-static void testDrawnEnvelopeFoldsTheFractionToOne() {
-    PlayParams p;
-    p.trigger.lengthFraction = 0.25;
-    CHECK(effectiveLengthFraction(p) == 0.25);   // staged: the knob is what it says
-
-    p.ampSpline.mode = EnvMode::Spline;
-    CHECK(effectiveLengthFraction(p) == 1.0);    // drawn: the whole take
-    CHECK(p.trigger.lengthFraction == 0.25);     // …and the stored value is untouched
-
-    // Flipping back restores the stored fraction, which is why the fold cannot be a write.
-    p.ampSpline.mode = EnvMode::Staged;
-    CHECK(effectiveLengthFraction(p) == 0.25);
-}
-
-// The fold reads the SAME predicate the engine's Gate refusal does, gating flags included: a
-// Spline mode on a DISABLED pitch/filter envelope binds no cursor, so it must not fold.
-static void testDisabledEnvelopesDoNotFoldTheFraction() {
-    PlayParams p;
-    p.trigger.lengthFraction = 0.5;
-
-    p.pitchSpline.mode = EnvMode::Spline;
-    CHECK(effectiveLengthFraction(p) == 0.5);    // pitchEnv.enabled is still false
-    p.pitchEnv.enabled = true;
-    CHECK(effectiveLengthFraction(p) == 1.0);
-
-    p.pitchEnv.enabled = false;
-    p.filterSpline.mode = EnvMode::Spline;
-    CHECK(effectiveLengthFraction(p) == 0.5);    // filter.enabled is still false
-    p.filter.enabled = true;
-    CHECK(effectiveLengthFraction(p) == 1.0);
+// The stored fraction is a wire double with no codec-side range check beyond finiteness, and
+// Voice::start clamps every one of these the same way. A span that ran past the source would
+// read off the end of the PCM; one derived from NaN would reach an undefined narrowing.
+static void testOutOfDomainFractionsClampToTheSpan() {
+    CHECK(triggerPlayLength(1.5, 1000, 0) == 1000);    // never past the post-start span
+    CHECK(triggerPlayLength(1.5, 1000, 200) == 800);
+    CHECK(triggerPlayLength(-0.5, 1000, 0) == 0);
+    CHECK(triggerPlayLength(std::nan(""), 1000, 0) == 0);
+    CHECK(triggerPlayLength(std::numeric_limits<double>::infinity(), 1000, 0) == 1000);
 }
 
 int main() {
-    testDrawnEnvelopeFoldsTheFractionToOne();
-    testDisabledEnvelopesDoNotFoldTheFraction();
+    testOutOfDomainFractionsClampToTheSpan();
     testPlayLengthNoStartPoint();
     testPlayLengthWithStartPoint();
     testPlayLengthZeroFrameCount();