Sizzletracker (Android)

A retro, grid-based music tracker for Android — monospace UI, pixel icons, demoscene-style pattern editing — playable equally with touch, keyboard, gamepad, and MIDI (USB or Bluetooth).

Features at a glance

• Tracker tab — 4-track pattern grid (note / velocity-hex / MIDI-channel per track), beat & bar coloring, tap-to-focus + drag-to-edit with haptics and scale-aware note entry; plus an 8-lane arrangement piano-roll (up to 256 beats) with A/B loop regions.
• Mix tab — 4 channels, each with an instrument + 4 FX slots, MIDI channel, volume, mute/solo.
• Toolbox tab — 16 slots for instruments (NES synth, sampler, SF2/XI) and effects (arp, transposer, LFO, tape delay, reverb, filters, 10-band EQ, bitcrusher). Every device has an auto-generated editor and text presets.
• Setup tab — .sng project save/load, color themes (with import/export), gamepad bindings, and searchable/collapsible MIDI bindings.
• Background playback with a media notification (Play/Pause/Stop).
• Two-thread design — Compose UI on the main thread, a sample-accurate sound engine on its own high-priority thread.

Build & run

Open the project in Android Studio (2024.1+), let it create the Gradle wrapper if prompted, and Run on an API 26+ device or emulator.

CLI (after the wrapper exists — gradle wrapper --gradle-version 8.9):

./gradlew assembleDebug

Where to start reading

See docs/DEVELOPER_HANDOVER.md — a from-scratch tour written for a developer new to Android: architecture, the file map, the "one action / one song / two threads" model, how to add an instrument or input, and an honest implemented-vs-TODO list.

Fastest orientation in code: model/Project.kt → input/InputAction.kt → ui/AppViewModel.kt → audio/AudioEngine.kt.

Project format

Songs use a human-readable .sng text format (see io/ProjectIo.kt), aligned in spirit with the desktop Sizzletracker; a byte-exact compatibility shim is a listed TODO in the handover doc.

License

TBD by the project owner.