add a TRACKER idea to the project

3 files changed, 46 insertions, 0 deletions

diff --git a/GEMINI.md b/GEMINI.md
index 234546f..47f6a58 100644
--- a/GEMINI.md
+++ b/GEMINI.md
@@ -8,6 +8,7 @@
 @3D.md
 @TODO.md
 @SPEC_EDITOR.md
+@TRACKER.md
 @PROCEDURAL.md
 @src/util/asset_manager.h
 @tools/asset_packer.cc
diff --git a/PROJECT_CONTEXT.md b/PROJECT_CONTEXT.md
index e356fe8..a938801 100644
--- a/PROJECT_CONTEXT.md
+++ b/PROJECT_CONTEXT.md
@@ -13,6 +13,7 @@ Audio:
 - 32 kHz, 16-bit mono
 - Procedurally generated samples
 - Real-time additive synthesis from spectrograms (IDCT)
+- Modifiable Loops and Patterns, w/ script to generate them (like a Tracker)
 
 Constraints:
 - Size-sensitive
@@ -85,3 +86,4 @@ Style:
 - **Synthesis**: Real-time additive synthesis from spectrograms via IDCT.
 - **Dynamic Updates**: Double-buffered spectrograms for live thread-safe updates.
 - **Procedural Library**: Melodies and spectral filters (noise, comb) generated at runtime.
+- **Pattern and loop**: spectrograms grouped as pattern and loops, and modifiers can be applied to loops (randomize, accents, etc.)
diff --git a/doc/TRACKER.md b/doc/TRACKER.md
new file mode 100644
index 0000000..cb14755
--- /dev/null
+++ b/doc/TRACKER.md
@@ -0,0 +1,43 @@
+# Minimal Audio Tracker
+
+in addition to being able to generate spectrograms (aka "Samples") on the
+fly and play them at once, we need a way to assemble samples (assets or 
+generated) into modifiable patterns and loops. Like what the Trackers were
+doing in the old time.
+
+## The idea
+
+A script can take a 'tracker music' text file that describes the sequence
+of samples (a 'pattern') in a first part. In a second part, these sequence
+a laid out with a timestamp (potentially overlapping) to generate the full
+music score.
+
+The patterns' samples (spectrograms) are not yet generated, it's just the
+'musical score' here. We still need to 'play' the score but with modifiers
+applied.
+
+### Modifiers
+
+For diversity, these essential patterns can be modified on the fly before
+being generated as spectrogram on the fly.
+Modifiers could be:
+  * randomize (for drums, e.g.)
+  * add accents and stresses
+  * modulate volume
+  * add distortion or noise
+  * add 'grain' and static noise
+  * flanger, vocoding, robotic voice, etc.
+  * etc.
+
+These modifiers are applied to a predefined pattern just before it's
+generated for playback (or assembling in the final track).
+
+### How would that work in practice?
+
+The musical score is a text file, that a tool will convert to run-time
+code to be compiled in the final binary demo64k.
+This generated code can be mixed with fixed code from the demo codebase
+itself (explosion predefined at a given time ,etc.)
+The baking is done at compile time, and the code will go in src/generated/
+
+