feat: Integrate tracker system and update project context documentation

- Implemented the basic tracker system with runtime support (tracker.h, tracker.cc).
- Added a sample music track file (assets/music.track).
- Created a tracker compiler tool (tools/tracker_compiler.cc) to generate music data.
- Updated CMakeLists.txt to build the tracker compiler and integrate generated data.
- Updated GEMINI.md to reflect new file locations and project context.

1 files changed, 159 insertions, 0 deletions

diff --git a/tools/tracker_compiler.cc b/tools/tracker_compiler.cc
new file mode 100644
index 0000000..491aebb
--- /dev/null
+++ b/tools/tracker_compiler.cc
@@ -0,0 +1,159 @@
+#include <cstdio>
+#include <fstream>
+#include <iostream>
+#include <string>
+#include <vector>
+#include <sstream>
+#include <map>
+
+struct Sample {
+    std::string name;
+    float freq, dur, amp, attack, harmonic_decay;
+    int harmonics;
+};
+
+struct Event {
+    float beat;
+    std::string sample_name;
+    float volume, pan;
+};
+
+struct Pattern {
+    std::string name;
+    std::vector<Event> events;
+};
+
+struct Trigger {
+    float time;
+    std::string pattern_name;
+};
+
+int main(int argc, char** argv) {
+    if (argc < 3) {
+        std::cerr << "Usage: " << argv[0] << " <input.track> <output.cc>" << std::endl;
+        return 1;
+    }
+
+    std::ifstream in(argv[1]);
+    if (!in.is_open()) {
+        std::cerr << "Could not open input file: " << argv[1] << std::endl;
+        return 1;
+    }
+
+    float bpm = 120.0f;
+    std::vector<Sample> samples;
+    std::map<std::string, int> sample_map;
+    std::vector<Pattern> patterns;
+    std::map<std::string, int> pattern_map;
+    std::vector<Trigger> score;
+
+    std::string line;
+    std::string current_section = "";
+
+    while (std::getline(in, line)) {
+        if (line.empty() || line[0] == '#') continue;
+
+        std::stringstream ss(line);
+        std::string cmd;
+        ss >> cmd;
+
+        if (cmd == "BPM") {
+            ss >> bpm;
+        } else if (cmd == "SAMPLE") {
+            Sample s;
+            std::string name;
+            ss >> name;
+            if (name.back() == ',') name.pop_back();
+            s.name = name;
+            
+            // Very simple parsing: freq, dur, amp, attack, harmonics, harmonic_decay
+            char comma;
+            ss >> s.freq >> comma >> s.dur >> comma >> s.amp >> comma >> s.attack >> comma >> s.harmonics >> comma >> s.harmonic_decay;
+            
+            sample_map[s.name] = samples.size();
+            samples.push_back(s);
+        } else if (cmd == "PATTERN") {
+            Pattern p;
+            ss >> p.name;
+            current_section = "PATTERN:" + p.name;
+            patterns.push_back(p);
+            pattern_map[p.name] = patterns.size() - 1;
+        } else if (cmd == "SCORE") {
+            current_section = "SCORE";
+        } else {
+            if (current_section.rfind("PATTERN:", 0) == 0) {
+                // Parse event: beat, sample, vol, pan
+                Event e;
+                float beat;
+                std::stringstream ss2(line);
+                ss2 >> beat;
+                char comma;
+                ss2 >> comma;
+                std::string sname;
+                ss2 >> sname;
+                if (sname.back() == ',') sname.pop_back();
+                e.beat = beat;
+                e.sample_name = sname;
+                ss2 >> e.volume >> comma >> e.pan;
+                patterns.back().events.push_back(e);
+            } else if (current_section == "SCORE") {
+                Trigger t;
+                float time;
+                std::stringstream ss2(line);
+                ss2 >> time;
+                char comma;
+                ss2 >> comma;
+                std::string pname;
+                ss2 >> pname;
+                t.time = time;
+                t.pattern_name = pname;
+                score.push_back(t);
+            }
+        }
+    }
+
+    std::ofstream out(argv[2]);
+    out << "// Generated by tracker_compiler. Do not edit.\n\n";
+    out << "#include \"audio/tracker.h\"\n\n";
+
+    out << "const NoteParams g_tracker_samples[] = {\n";
+    for (const auto& s : samples) {
+        out << "    { " << s.freq << "f, " << s.dur << "f, " << s.amp << "f, " << s.attack << "f, 0.0f, 0.0f, 0.0f, " 
+            << s.harmonics << ", " << s.harmonic_decay << "f, 0.0f, 0.0f }, // " << s.name << "\n";
+    }
+    out << "};
+";
+    out << "const uint32_t g_tracker_samples_count = " << samples.size() << ";\n\n";
+
+    for (const auto& p : patterns) {
+        out << "static const TrackerEvent PATTERN_EVENTS_" << p.name << "[] = {\n";
+        for (const auto& e : p.events) {
+            out << "    { " << e.beat << "f, " << sample_map[e.sample_name] << ", " << e.volume << "f, " << e.pan << "f },\n";
+        }
+        out << "};
+";
+    }
+    out << "\n";
+
+    out << "const TrackerPattern g_tracker_patterns[] = {\n";
+    for (const auto& p : patterns) {
+        out << "    { PATTERN_EVENTS_" << p.name << ", " << p.events.size() << ", 4.0f }, // " << p.name << "\n";
+    }
+    out << "};
+";
+    out << "const uint32_t g_tracker_patterns_count = " << patterns.size() << ";\n\n";
+
+    out << "static const TrackerPatternTrigger SCORE_TRIGGERS[] = {\n";
+    for (const auto& t : score) {
+        out << "    { " << t.time << "f, " << pattern_map[t.pattern_name] << " },\n";
+    }
+    out << "};
+\n";
+
+    out << "const TrackerScore g_tracker_score = {\n";
+    out << "    SCORE_TRIGGERS, " << score.size() << ", " << bpm << "f\n";
+    out << "};
+";
+
+    return 0;
+}