refactor(audio): Convert tracker to unit-less timing system

Changes tracker timing from beat-based to unit-less system to separate
musical structure from BPM-dependent playback speed.

TIMING CONVENTION:
- 1 unit = 4 beats (by convention)
- Conversion: seconds = units * (4 / BPM) * 60
- At 120 BPM: 1 unit = 2 seconds

BENEFITS:
- Pattern structure independent of BPM
- BPM changes only affect playback speed, not structure
- Easier pattern composition (0.00-1.00 for typical 4-beat pattern)
- Fixes issue where patterns played for 2s instead of expected duration

DATA STRUCTURES (tracker.h):
- TrackerEvent.beat → TrackerEvent.unit_time
- TrackerPattern.num_beats → TrackerPattern.unit_length
- TrackerPatternTrigger.time_sec → TrackerPatternTrigger.unit_time

RUNTIME (tracker.cc):
- Added BEATS_PER_UNIT constant (4.0)
- Convert units to seconds at playback time using BPM
- Pattern remains active for full unit_length duration
- Fixed premature pattern deactivation bug

COMPILER (tracker_compiler.cc):
- Parse LENGTH parameter from PATTERN lines (defaults to 1.0)
- Parse unit_time instead of beat values
- Generate code with unit-less timing

ASSETS:
- test_demo.track: converted to unit-less (8 score triggers)
- music.track: converted to unit-less (all patterns)
- Events: beat/4 conversion (e.g., beat 2.0 → unit 0.50)
- Score: seconds/unit_duration (e.g., 4s → 2.0 units at 120 BPM)

VISUALIZER (track_visualizer/index.html):
- Parse LENGTH parameter and BPM directive
- Convert unit-less time to seconds for rendering
- Update tick positioning to use unit_time
- Display correct pattern durations

DOCUMENTATION (doc/TRACKER.md):
- Added complete .track format specification
- Timing conversion reference table
- Examples with unit-less timing
- Pattern LENGTH parameter documentation

FILES MODIFIED:
- src/audio/tracker.{h,cc} (data structures + runtime conversion)
- tools/tracker_compiler.cc (parser + code generation)
- assets/{test_demo,music}.track (converted to unit-less)
- tools/track_visualizer/index.html (BPM-aware rendering)
- doc/TRACKER.md (format documentation)
- convert_track.py (conversion utility script)

TEST RESULTS:
- test_demo builds and runs correctly
- demo64k builds successfully
- Generated code verified (unit-less values in music_data.cc)

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

4 files changed, 225 insertions, 216 deletions

diff --git a/src/audio/tracker.cc b/src/audio/tracker.cc
index 7ad5a67..9ae772e 100644
--- a/src/audio/tracker.cc
+++ b/src/audio/tracker.cc
@@ -212,19 +212,24 @@ static void trigger_note_event(const TrackerEvent& event) {
 }
 
 void tracker_update(float music_time_sec) {
+  // Unit-less timing: 1 unit = 4 beats (by convention)
+  const float BEATS_PER_UNIT = 4.0f;
+  const float unit_duration_sec = (BEATS_PER_UNIT / g_tracker_score.bpm) * 60.0f;
+
   // Step 1: Process new pattern triggers
   while (g_last_trigger_idx < g_tracker_score.num_triggers) {
     const TrackerPatternTrigger& trigger =
         g_tracker_score.triggers[g_last_trigger_idx];
 
-    if (trigger.time_sec > music_time_sec)
+    const float trigger_time_sec = trigger.unit_time * unit_duration_sec;
+    if (trigger_time_sec > music_time_sec)
       break;
 
     // Add this pattern to active patterns list
     const int slot = get_free_pattern_slot();
     if (slot != -1) {
       g_active_patterns[slot].pattern_id = trigger.pattern_id;
-      g_active_patterns[slot].start_music_time = trigger.time_sec;
+      g_active_patterns[slot].start_music_time = trigger_time_sec;
       g_active_patterns[slot].next_event_idx = 0;
       g_active_patterns[slot].active = true;
     }
@@ -233,8 +238,6 @@ void tracker_update(float music_time_sec) {
   }
 
   // Step 2: Update all active patterns and trigger individual events
-  const float beat_duration = 60.0f / g_tracker_score.bpm;
-
   for (int i = 0; i < MAX_SPECTROGRAMS; ++i) {
     if (!g_active_patterns[i].active)
       continue;
@@ -242,15 +245,15 @@ void tracker_update(float music_time_sec) {
     ActivePattern& active = g_active_patterns[i];
     const TrackerPattern& pattern = g_tracker_patterns[active.pattern_id];
 
-    // Calculate elapsed beats since pattern started
+    // Calculate elapsed unit-less time since pattern started
     const float elapsed_music_time = music_time_sec - active.start_music_time;
-    const float elapsed_beats = elapsed_music_time / beat_duration;
+    const float elapsed_units = elapsed_music_time / unit_duration_sec;
 
-    // Trigger all events that have passed their beat time
+    // Trigger all events that have passed their unit time
     while (active.next_event_idx < pattern.num_events) {
       const TrackerEvent& event = pattern.events[active.next_event_idx];
 
-      if (event.beat > elapsed_beats)
+      if (event.unit_time > elapsed_units)
         break; // This event hasn't reached its time yet
 
       // Trigger this event as an individual voice
@@ -259,8 +262,8 @@ void tracker_update(float music_time_sec) {
       active.next_event_idx++;
     }
 
-    // If all events have been triggered, mark pattern as complete
-    if (active.next_event_idx >= pattern.num_events) {
+    // Pattern remains active until full duration elapses
+    if (elapsed_units >= pattern.unit_length) {
       active.active = false;
     }
   }
diff --git a/src/audio/tracker.h b/src/audio/tracker.h
index 336f77f..4cd011b 100644
--- a/src/audio/tracker.h
+++ b/src/audio/tracker.h
@@ -8,7 +8,7 @@
 #include <cstdint>
 
 struct TrackerEvent {
-  float beat;
+  float unit_time;  // Unit-less time within pattern (0.0 to pattern.unit_length)
   uint16_t sample_id;
   float volume;
   float pan;
@@ -17,11 +17,11 @@ struct TrackerEvent {
 struct TrackerPattern {
   const TrackerEvent* events;
   uint32_t num_events;
-  float num_beats;
+  float unit_length;  // Pattern duration in units (typically 1.0 for 4-beat patterns)
 };
 
 struct TrackerPatternTrigger {
-  float time_sec;
+  float unit_time;  // Unit-less time when pattern triggers
   uint16_t pattern_id;
   // Modifiers could be added here
 };
@@ -29,7 +29,7 @@ struct TrackerPatternTrigger {
 struct TrackerScore {
   const TrackerPatternTrigger* triggers;
   uint32_t num_triggers;
-  float bpm;
+  float bpm;  // BPM is used only for playback scaling (1 unit = 4 beats)
 };
 
 // Global music data generated by tracker_compiler
diff --git a/src/generated/music_data.cc b/src/generated/music_data.cc
index ee28402..7db925a 100644
--- a/src/generated/music_data.cc
+++ b/src/generated/music_data.cc
@@ -24,8 +24,9 @@ const NoteParams g_tracker_samples[] = {
     { 196.0f, 0.50f, 1.0f, 0.01f, 0.0f, 0.0f, 0.0f, 3, 0.6f, 0.0f, 0.0f }, // NOTE_G3
     { 146.8f, 0.50f, 1.0f, 0.01f, 0.0f, 0.0f, 0.0f, 3, 0.6f, 0.0f, 0.0f }, // NOTE_D3
     { 65.4f, 0.50f, 1.0f, 0.01f, 0.0f, 0.0f, 0.0f, 3, 0.6f, 0.0f, 0.0f }, // NOTE_C2
+    { 73.4f, 0.50f, 1.0f, 0.01f, 0.0f, 0.0f, 0.0f, 3, 0.6f, 0.0f, 0.0f }, // NOTE_D2
 };
-const uint32_t g_tracker_samples_count = 19;
+const uint32_t g_tracker_samples_count = 20;
 
 const AssetId g_tracker_sample_assets[] = {
   AssetId::ASSET_KICK_1,
@@ -47,151 +48,152 @@ const AssetId g_tracker_sample_assets[] = {
   AssetId::ASSET_LAST_ID,
   AssetId::ASSET_LAST_ID,
   AssetId::ASSET_LAST_ID,
+  AssetId::ASSET_LAST_ID,
 };
 
 static const TrackerEvent PATTERN_EVENTS_kick_basic[] = {
-    { 0.0f, 0, 1.0f, 0.0f },
-    { 2.0f, 0, 1.0f, 0.0f },
+    { 0.00f, 0, 1.0f, 0.0f },
+    { 0.50f, 0, 1.0f, 0.0f },
 };
 static const TrackerEvent PATTERN_EVENTS_kick_varied[] = {
-    { 0.0f, 2, 1.0f, 0.0f },
-    { 2.0f, 0, 0.9f, 0.0f },
+    { 0.00f, 2, 1.0f, 0.0f },
+    { 0.50f, 0, 0.9f, 0.0f },
 };
 static const TrackerEvent PATTERN_EVENTS_kick_dense[] = {
-    { 0.0f, 0, 1.0f, 0.0f },
-    { 0.5f, 2, 0.6f, -0.2f },
-    { 1.0f, 0, 0.9f, 0.0f },
-    { 1.5f, 2, 0.6f, 0.2f },
-    { 2.0f, 0, 1.0f, 0.0f },
-    { 2.5f, 2, 0.6f, -0.2f },
-    { 3.0f, 0, 0.9f, 0.0f },
-    { 3.5f, 2, 0.6f, 0.2f },
+    { 0.00f, 0, 1.0f, 0.0f },
+    { 0.12f, 2, 0.6f, -0.2f },
+    { 0.25f, 0, 0.9f, 0.0f },
+    { 0.38f, 2, 0.6f, 0.2f },
+    { 0.50f, 0, 1.0f, 0.0f },
+    { 0.62f, 2, 0.6f, -0.2f },
+    { 0.75f, 0, 0.9f, 0.0f },
+    { 0.88f, 2, 0.6f, 0.2f },
 };
 static const TrackerEvent PATTERN_EVENTS_snare_basic[] = {
-    { 1.0f, 3, 1.1f, 0.1f },
-    { 3.0f, 3, 1.1f, 0.1f },
+    { 0.25f, 3, 1.1f, 0.1f },
+    { 0.75f, 3, 1.1f, 0.1f },
 };
 static const TrackerEvent PATTERN_EVENTS_snare_varied[] = {
-    { 1.0f, 4, 1.0f, -0.1f },
-    { 3.0f, 0, 1.1f, 0.1f },
+    { 0.25f, 4, 1.0f, -0.1f },
+    { 0.75f, 0, 1.1f, 0.1f },
 };
 static const TrackerEvent PATTERN_EVENTS_snare_dense[] = {
-    { 1.0f, 3, 1.1f, 0.1f },
-    { 2.5f, 6, 0.9f, 0.0f },
-    { 3.5f, 0, 0.9f, 0.0f },
+    { 0.25f, 3, 1.1f, 0.1f },
+    { 0.62f, 6, 0.9f, 0.0f },
+    { 0.88f, 0, 0.9f, 0.0f },
 };
 static const TrackerEvent PATTERN_EVENTS_hihat_basic[] = {
-    { 0.0f, 8, 0.7f, -0.3f },
-    { 0.5f, 7, 0.3f, 0.3f },
-    { 1.0f, 8, 0.7f, -0.3f },
-    { 1.5f, 7, 0.3f, 0.3f },
-    { 2.0f, 8, 0.7f, -0.3f },
-    { 2.5f, 7, 0.3f, 0.3f },
-    { 3.0f, 8, 0.7f, -0.3f },
-    { 3.5f, 7, 0.3f, 0.3f },
+    { 0.00f, 8, 0.7f, -0.3f },
+    { 0.12f, 7, 0.3f, 0.3f },
+    { 0.25f, 8, 0.7f, -0.3f },
+    { 0.38f, 7, 0.3f, 0.3f },
+    { 0.50f, 8, 0.7f, -0.3f },
+    { 0.62f, 7, 0.3f, 0.3f },
+    { 0.75f, 8, 0.7f, -0.3f },
+    { 0.88f, 7, 0.3f, 0.3f },
 };
 static const TrackerEvent PATTERN_EVENTS_hihat_varied[] = {
-    { 0.0f, 10, 0.7f, -0.3f },
-    { 0.5f, 7, 0.3f, 0.3f },
-    { 1.0f, 0, 0.6f, -0.2f },
-    { 1.5f, 7, 0.3f, 0.3f },
-    { 2.0f, 10, 0.7f, -0.3f },
-    { 2.5f, 7, 0.3f, 0.3f },
-    { 3.0f, 0, 0.6f, -0.2f },
-    { 3.5f, 7, 0.3f, 0.3f },
+    { 0.00f, 10, 0.7f, -0.3f },
+    { 0.12f, 7, 0.3f, 0.3f },
+    { 0.25f, 0, 0.6f, -0.2f },
+    { 0.38f, 7, 0.3f, 0.3f },
+    { 0.50f, 10, 0.7f, -0.3f },
+    { 0.62f, 7, 0.3f, 0.3f },
+    { 0.75f, 0, 0.6f, -0.2f },
+    { 0.88f, 7, 0.3f, 0.3f },
 };
 static const TrackerEvent PATTERN_EVENTS_crash[] = {
-    { 0.0f, 11, 0.9f, 0.0f },
+    { 0.00f, 11, 0.9f, 0.0f },
 };
 static const TrackerEvent PATTERN_EVENTS_ride[] = {
-    { 0.0f, 12, 0.8f, 0.2f },
+    { 0.00f, 12, 0.8f, 0.2f },
 };
 static const TrackerEvent PATTERN_EVENTS_ride_fast[] = {
-    { 0.0f, 12, 0.8f, 0.2f },
-    { 0.5f, 12, 0.6f, 0.2f },
-    { 1.0f, 12, 0.8f, 0.2f },
-    { 1.5f, 12, 0.6f, 0.2f },
-    { 2.0f, 12, 0.8f, 0.2f },
-    { 2.5f, 12, 0.6f, 0.2f },
-    { 3.0f, 12, 0.8f, 0.2f },
-    { 3.5f, 12, 0.6f, 0.2f },
+    { 0.00f, 12, 0.8f, 0.2f },
+    { 0.12f, 12, 0.6f, 0.2f },
+    { 0.25f, 12, 0.8f, 0.2f },
+    { 0.38f, 12, 0.6f, 0.2f },
+    { 0.50f, 12, 0.8f, 0.2f },
+    { 0.62f, 12, 0.6f, 0.2f },
+    { 0.75f, 12, 0.8f, 0.2f },
+    { 0.88f, 12, 0.6f, 0.2f },
 };
 static const TrackerEvent PATTERN_EVENTS_splash[] = {
-    { 0.0f, 13, 0.7f, -0.2f },
+    { 0.00f, 13, 0.7f, -0.2f },
 };
 static const TrackerEvent PATTERN_EVENTS_bass_e_soft[] = {
-    { 0.0f, 15, 0.4f, 0.0f },
-    { 2.0f, 15, 0.3f, 0.0f },
+    { 0.00f, 15, 0.4f, 0.0f },
+    { 0.50f, 15, 0.3f, 0.0f },
 };
 static const TrackerEvent PATTERN_EVENTS_bass_e[] = {
-    { 0.0f, 15, 0.5f, 0.0f },
-    { 1.0f, 15, 0.4f, 0.0f },
-    { 2.0f, 15, 0.5f, 0.0f },
-    { 2.5f, 15, 0.3f, 0.0f },
-    { 3.0f, 15, 0.4f, 0.0f },
+    { 0.00f, 15, 0.5f, 0.0f },
+    { 0.25f, 15, 0.4f, 0.0f },
+    { 0.50f, 15, 0.5f, 0.0f },
+    { 0.62f, 15, 0.3f, 0.0f },
+    { 0.75f, 15, 0.4f, 0.0f },
 };
 static const TrackerEvent PATTERN_EVENTS_bass_eg[] = {
-    { 0.0f, 15, 0.5f, 0.0f },
-    { 1.0f, 15, 0.4f, 0.0f },
-    { 2.0f, 16, 0.5f, 0.0f },
-    { 3.0f, 16, 0.4f, 0.0f },
+    { 0.00f, 15, 0.5f, 0.0f },
+    { 0.25f, 15, 0.4f, 0.0f },
+    { 0.50f, 16, 0.5f, 0.0f },
+    { 0.75f, 16, 0.4f, 0.0f },
 };
 static const TrackerEvent PATTERN_EVENTS_bass_progression[] = {
-    { 0.0f, 15, 0.5f, 0.0f },
-    { 1.0f, 17, 0.4f, 0.0f },
-    { 2.0f, 18, 0.5f, 0.0f },
-    { 3.0f, 16, 0.4f, 0.0f },
+    { 0.00f, 15, 0.5f, 0.0f },
+    { 0.25f, 17, 0.4f, 0.0f },
+    { 0.50f, 18, 0.5f, 0.0f },
+    { 0.75f, 16, 0.4f, 0.0f },
 };
 static const TrackerEvent PATTERN_EVENTS_bass_synco_1[] = {
-    { 0.0f, 15, 0.6f, 0.0f },
-    { 0.2f, 15, 0.5f, 0.1f },
-    { 0.8f, 15, 0.6f, -0.1f },
-    { 1.5f, 15, 0.5f, 0.0f },
-    { 2.0f, 15, 0.6f, 0.0f },
-    { 2.8f, 16, 0.6f, 0.1f },
-    { 3.2f, 15, 0.5f, 0.0f },
+    { 0.00f, 15, 0.6f, 0.0f },
+    { 0.06f, 15, 0.5f, 0.1f },
+    { 0.19f, 15, 0.6f, -0.1f },
+    { 0.38f, 15, 0.5f, 0.0f },
+    { 0.50f, 15, 0.6f, 0.0f },
+    { 0.69f, 16, 0.6f, 0.1f },
+    { 0.81f, 15, 0.5f, 0.0f },
 };
 static const TrackerEvent PATTERN_EVENTS_bass_synco_2[] = {
-    { 0.0f, 15, 0.6f, 0.0f },
-    { 0.5f, 17, 0.6f, -0.1f },
-    { 1.2f, 15, 0.5f, 0.1f },
-    { 1.8f, 17, 0.5f, 0.0f },
-    { 2.0f, 18, 0.6f, 0.0f },
-    { 2.5f, 15, 0.5f, 0.1f },
-    { 3.0f, 16, 0.6f, 0.0f },
-    { 3.5f, 15, 0.5f, -0.1f },
+    { 0.00f, 15, 0.6f, 0.0f },
+    { 0.12f, 17, 0.6f, -0.1f },
+    { 0.31f, 15, 0.5f, 0.1f },
+    { 0.44f, 17, 0.5f, 0.0f },
+    { 0.50f, 18, 0.6f, 0.0f },
+    { 0.62f, 15, 0.5f, 0.1f },
+    { 0.75f, 16, 0.6f, 0.0f },
+    { 0.88f, 15, 0.5f, -0.1f },
 };
 static const TrackerEvent PATTERN_EVENTS_bass_synco_3[] = {
-    { 0.0f, 15, 0.6f, 0.0f },
-    { 0.2f, 15, 0.5f, 0.0f },
-    { 0.5f, 15, 0.6f, 0.1f },
-    { 1.0f, 16, 0.6f, 0.0f },
-    { 1.5f, 15, 0.5f, -0.1f },
-    { 2.2f, 17, 0.6f, 0.0f },
-    { 2.8f, 15, 0.5f, 0.1f },
-    { 3.5f, 15, 0.6f, 0.0f },
+    { 0.00f, 15, 0.6f, 0.0f },
+    { 0.06f, 15, 0.5f, 0.0f },
+    { 0.12f, 15, 0.6f, 0.1f },
+    { 0.25f, 16, 0.6f, 0.0f },
+    { 0.38f, 15, 0.5f, -0.1f },
+    { 0.56f, 19, 0.6f, 0.0f },
+    { 0.69f, 15, 0.5f, 0.1f },
+    { 0.88f, 15, 0.6f, 0.0f },
 };
 
 const TrackerPattern g_tracker_patterns[] = {
-    { PATTERN_EVENTS_kick_basic, 2, 4.0f }, // kick_basic
-    { PATTERN_EVENTS_kick_varied, 2, 4.0f }, // kick_varied
-    { PATTERN_EVENTS_kick_dense, 8, 4.0f }, // kick_dense
-    { PATTERN_EVENTS_snare_basic, 2, 4.0f }, // snare_basic
-    { PATTERN_EVENTS_snare_varied, 2, 4.0f }, // snare_varied
-    { PATTERN_EVENTS_snare_dense, 3, 4.0f }, // snare_dense
-    { PATTERN_EVENTS_hihat_basic, 8, 4.0f }, // hihat_basic
-    { PATTERN_EVENTS_hihat_varied, 8, 4.0f }, // hihat_varied
-    { PATTERN_EVENTS_crash, 1, 4.0f }, // crash
-    { PATTERN_EVENTS_ride, 1, 4.0f }, // ride
-    { PATTERN_EVENTS_ride_fast, 8, 4.0f }, // ride_fast
-    { PATTERN_EVENTS_splash, 1, 4.0f }, // splash
-    { PATTERN_EVENTS_bass_e_soft, 2, 4.0f }, // bass_e_soft
-    { PATTERN_EVENTS_bass_e, 5, 4.0f }, // bass_e
-    { PATTERN_EVENTS_bass_eg, 4, 4.0f }, // bass_eg
-    { PATTERN_EVENTS_bass_progression, 4, 4.0f }, // bass_progression
-    { PATTERN_EVENTS_bass_synco_1, 7, 4.0f }, // bass_synco_1
-    { PATTERN_EVENTS_bass_synco_2, 8, 4.0f }, // bass_synco_2
-    { PATTERN_EVENTS_bass_synco_3, 8, 4.0f }, // bass_synco_3
+    { PATTERN_EVENTS_kick_basic, 2, 1.00f }, // kick_basic
+    { PATTERN_EVENTS_kick_varied, 2, 1.00f }, // kick_varied
+    { PATTERN_EVENTS_kick_dense, 8, 1.00f }, // kick_dense
+    { PATTERN_EVENTS_snare_basic, 2, 1.00f }, // snare_basic
+    { PATTERN_EVENTS_snare_varied, 2, 1.00f }, // snare_varied
+    { PATTERN_EVENTS_snare_dense, 3, 1.00f }, // snare_dense
+    { PATTERN_EVENTS_hihat_basic, 8, 1.00f }, // hihat_basic
+    { PATTERN_EVENTS_hihat_varied, 8, 1.00f }, // hihat_varied
+    { PATTERN_EVENTS_crash, 1, 1.00f }, // crash
+    { PATTERN_EVENTS_ride, 1, 1.00f }, // ride
+    { PATTERN_EVENTS_ride_fast, 8, 1.00f }, // ride_fast
+    { PATTERN_EVENTS_splash, 1, 1.00f }, // splash
+    { PATTERN_EVENTS_bass_e_soft, 2, 1.00f }, // bass_e_soft
+    { PATTERN_EVENTS_bass_e, 5, 1.00f }, // bass_e
+    { PATTERN_EVENTS_bass_eg, 4, 1.00f }, // bass_eg
+    { PATTERN_EVENTS_bass_progression, 4, 1.00f }, // bass_progression
+    { PATTERN_EVENTS_bass_synco_1, 7, 1.00f }, // bass_synco_1
+    { PATTERN_EVENTS_bass_synco_2, 8, 1.00f }, // bass_synco_2
+    { PATTERN_EVENTS_bass_synco_3, 8, 1.00f }, // bass_synco_3
 };
 const uint32_t g_tracker_patterns_count = 19;
 
@@ -199,88 +201,88 @@ static const TrackerPatternTrigger SCORE_TRIGGERS[] = {
     { 0.0f, 8 },
     { 0.0f, 0 },
     { 0.0f, 6 },
+    { 0.5f, 0 },
+    { 0.5f, 3 },
+    { 0.5f, 6 },
+    { 1.0f, 9 },
+    { 1.0f, 1 },
+    { 1.0f, 3 },
+    { 1.0f, 7 },
+    { 1.5f, 1 },
+    { 1.5f, 4 },
+    { 1.5f, 7 },
+    { 2.0f, 11 },
     { 2.0f, 0 },
     { 2.0f, 3 },
     { 2.0f, 6 },
-    { 4.0f, 9 },
-    { 4.0f, 1 },
-    { 4.0f, 3 },
+    { 2.0f, 12 },
+    { 2.5f, 1 },
+    { 2.5f, 4 },
+    { 2.5f, 7 },
+    { 2.5f, 12 },
+    { 3.0f, 9 },
+    { 3.0f, 0 },
+    { 3.0f, 3 },
+    { 3.0f, 6 },
+    { 3.0f, 13 },
+    { 3.5f, 1 },
+    { 3.5f, 4 },
+    { 3.5f, 7 },
+    { 3.5f, 14 },
+    { 4.0f, 8 },
+    { 4.0f, 2 },
+    { 4.0f, 5 },
     { 4.0f, 7 },
-    { 6.0f, 1 },
-    { 6.0f, 4 },
+    { 4.0f, 13 },
+    { 4.5f, 2 },
+    { 4.5f, 5 },
+    { 4.5f, 6 },
+    { 4.5f, 15 },
+    { 5.0f, 9 },
+    { 5.0f, 2 },
+    { 5.0f, 5 },
+    { 5.0f, 7 },
+    { 5.0f, 13 },
+    { 5.5f, 2 },
+    { 5.5f, 5 },
+    { 5.5f, 6 },
+    { 5.5f, 14 },
+    { 6.0f, 11 },
+    { 6.0f, 2 },
+    { 6.0f, 5 },
     { 6.0f, 7 },
-    { 8.0f, 11 },
-    { 8.0f, 0 },
-    { 8.0f, 3 },
-    { 8.0f, 6 },
-    { 8.0f, 12 },
-    { 10.0f, 1 },
-    { 10.0f, 4 },
-    { 10.0f, 7 },
-    { 10.0f, 12 },
-    { 12.0f, 9 },
-    { 12.0f, 0 },
-    { 12.0f, 3 },
-    { 12.0f, 6 },
-    { 12.0f, 13 },
-    { 14.0f, 1 },
-    { 14.0f, 4 },
-    { 14.0f, 7 },
-    { 14.0f, 14 },
-    { 16.0f, 8 },
-    { 16.0f, 2 },
-    { 16.0f, 5 },
-    { 16.0f, 7 },
-    { 16.0f, 13 },
-    { 18.0f, 2 },
-    { 18.0f, 5 },
-    { 18.0f, 6 },
-    { 18.0f, 15 },
-    { 20.0f, 9 },
-    { 20.0f, 2 },
-    { 20.0f, 5 },
-    { 20.0f, 7 },
-    { 20.0f, 13 },
-    { 22.0f, 2 },
-    { 22.0f, 5 },
-    { 22.0f, 6 },
-    { 22.0f, 14 },
-    { 24.0f, 11 },
-    { 24.0f, 2 },
-    { 24.0f, 5 },
-    { 24.0f, 7 },
-    { 24.0f, 15 },
-    { 26.0f, 2 },
-    { 26.0f, 5 },
-    { 26.0f, 6 },
-    { 26.0f, 13 },
-    { 28.0f, 10 },
-    { 28.0f, 0 },
-    { 28.0f, 4 },
-    { 28.0f, 7 },
-    { 28.0f, 14 },
-    { 30.0f, 1 },
-    { 30.0f, 3 },
-    { 30.0f, 6 },
-    { 30.0f, 15 },
-    { 31.0f, 6 },
-    { 32.0f, 8 },
-    { 32.0f, 10 },
-    { 32.0f, 2 },
-    { 32.0f, 5 },
-    { 32.0f, 7 },
-    { 32.0f, 16 },
-    { 34.0f, 10 },
-    { 34.0f, 2 },
-    { 34.0f, 5 },
-    { 34.0f, 6 },
-    { 34.0f, 17 },
-    { 36.0f, 10 },
-    { 36.0f, 2 },
-    { 36.0f, 5 },
-    { 36.0f, 7 },
-    { 36.0f, 18 },
-    { 38.0f, 8 },
+    { 6.0f, 15 },
+    { 6.5f, 2 },
+    { 6.5f, 5 },
+    { 6.5f, 6 },
+    { 6.5f, 13 },
+    { 7.0f, 10 },
+    { 7.0f, 0 },
+    { 7.0f, 4 },
+    { 7.0f, 7 },
+    { 7.0f, 14 },
+    { 7.5f, 1 },
+    { 7.5f, 3 },
+    { 7.5f, 6 },
+    { 7.5f, 15 },
+    { 7.8f, 6 },
+    { 8.0f, 8 },
+    { 8.0f, 10 },
+    { 8.0f, 2 },
+    { 8.0f, 5 },
+    { 8.0f, 7 },
+    { 8.0f, 16 },
+    { 8.5f, 10 },
+    { 8.5f, 2 },
+    { 8.5f, 5 },
+    { 8.5f, 6 },
+    { 8.5f, 17 },
+    { 9.0f, 10 },
+    { 9.0f, 2 },
+    { 9.0f, 5 },
+    { 9.0f, 7 },
+    { 9.0f, 18 },
+    { 9.5f, 8 },
 };
 
 const TrackerScore g_tracker_score = {
@@ -290,19 +292,19 @@ const TrackerScore g_tracker_score = {
 // ============================================================
 // RESOURCE USAGE ANALYSIS (for synth.h configuration)
 // ============================================================
-// Total samples: 19 (15 assets + 4 generated notes)
+// Total samples: 20 (15 assets + 5 generated notes)
 // Max simultaneous pattern triggers: 6
 // Estimated max polyphony: 24 voices
 // 
 // REQUIRED (minimum to avoid pool exhaustion):
 //   MAX_VOICES: 24
-//   MAX_SPECTROGRAMS: 111 (no caching)
+//   MAX_SPECTROGRAMS: 135 (no caching)
 // 
 // RECOMMENDED (with 50% safety margin):
 //   MAX_VOICES: 48
-//   MAX_SPECTROGRAMS: 166 (no caching)
+//   MAX_SPECTROGRAMS: 202 (no caching)
 // 
 // NOTE: With spectrogram caching by note parameters,
-//       MAX_SPECTROGRAMS could be reduced to ~19
+//       MAX_SPECTROGRAMS could be reduced to ~20
 // ============================================================
 
diff --git a/src/generated/test_demo_music.cc b/src/generated/test_demo_music.cc
index 9e04741..f77984e 100644
--- a/src/generated/test_demo_music.cc
+++ b/src/generated/test_demo_music.cc
@@ -20,36 +20,40 @@ const AssetId g_tracker_sample_assets[] = {
 };
 
 static const TrackerEvent PATTERN_EVENTS_drums_basic[] = {
-    { 0.0f, 0, 1.0f, 0.0f },
-    { 0.0f, 3, 0.5f, 0.0f },
-    { 1.0f, 1, 0.9f, 0.0f },
-    { 2.0f, 0, 1.0f, 0.0f },
-    { 3.0f, 1, 0.9f, 0.0f },
+    { 0.00f, 0, 1.0f, 0.0f },
+    { 0.00f, 3, 0.5f, 0.0f },
+    { 0.25f, 1, 0.9f, 0.0f },
+    { 0.50f, 0, 1.0f, 0.0f },
+    { 0.75f, 1, 0.9f, 0.0f },
 };
 static const TrackerEvent PATTERN_EVENTS_drums_with_crash[] = {
-    { 0.0f, 0, 1.0f, 0.0f },
-    { 0.0f, 2, 0.9f, 0.0f },
-    { 0.0f, 3, 0.5f, 0.0f },
-    { 1.0f, 1, 0.9f, 0.0f },
-    { 2.0f, 0, 1.0f, 0.0f },
-    { 3.0f, 1, 0.9f, 0.0f },
+    { 0.00f, 0, 1.0f, 0.0f },
+    { 0.00f, 2, 0.9f, 0.0f },
+    { 0.00f, 3, 0.5f, 0.0f },
+    { 0.25f, 1, 0.9f, 0.0f },
+    { 0.50f, 0, 1.0f, 0.0f },
+    { 0.75f, 1, 0.9f, 0.0f },
 };
 
 const TrackerPattern g_tracker_patterns[] = {
-    { PATTERN_EVENTS_drums_basic, 5, 4.0f }, // drums_basic
-    { PATTERN_EVENTS_drums_with_crash, 6, 4.0f }, // drums_with_crash
+    { PATTERN_EVENTS_drums_basic, 5, 1.00f }, // drums_basic
+    { PATTERN_EVENTS_drums_with_crash, 6, 1.00f }, // drums_with_crash
 };
 const uint32_t g_tracker_patterns_count = 2;
 
 static const TrackerPatternTrigger SCORE_TRIGGERS[] = {
     { 0.0f, 0 },
-    { 4.0f, 1 },
-    { 8.0f, 0 },
-    { 12.0f, 1 },
+    { 1.0f, 0 },
+    { 2.0f, 1 },
+    { 3.0f, 0 },
+    { 4.0f, 0 },
+    { 5.0f, 0 },
+    { 6.0f, 1 },
+    { 7.0f, 0 },
 };
 
 const TrackerScore g_tracker_score = {
-    SCORE_TRIGGERS, 4, 120.0f
+    SCORE_TRIGGERS, 8, 120.0f
 };
 
 // ============================================================