Yacht - The Handheld Music Studio

Yacht is a music creation tool designed for the Playdate handheld gaming system. It features a piano roll sequencer, drum pattern editor, synthesizer controls, and song arrangement capabilities.

https://kurogedelic.itch.io/yacht

Features

• Wrote by Playdate LUA
• Piano roll with note editing and automation
• Drum pattern editor with velocity, accent, chance and per-step mute
• 3 synthesizer channels with comprehensive sound design controls
• Three voice modes per synth: oscillator, wavetable and sampler
• Sample-based drum machine with 6 drum slots
• Mixer with volume and pan controls
• Pattern-based song arrangement system
• Realtime visualization of playing notes

Synth voice modes

The Mode column on the left of the SynthEdit page picks what each of the three synths plays. A + up/down cycles the mode.

Mode	Voice	Notes
Osc	Built-in waveform	Form picks one of 8 waveforms; ① / ② are the synth parameters
Wave	The sample sliced into 256-frame wavetable cells	Scan moves across the table and can be driven from the MOD matrix
Smpl	The sample played back pitched	MIDI note 60 (C4) plays at normal speed

Selecting Wave or Smpl swaps the oscillator panel for the sampler panel, which replaces the scope and the Form slider with these controls:

Control	What it does
Sample slot	Shows the loaded sample; A opens the picker
REC	A records from the microphone, A again stops early
Scan / Len	Wavetable position, or playback length for a plain sample
Tune	Transposes the voice by up to +/- 2 octaves

Filter, amplifier, LFO and envelope apply in every mode. If a sample cannot be loaded the voice falls back to the oscillator and the slot label shows a !.

Recordings are captured as up to 4 seconds of 16-bit mono, stored in the app's Data folder as recordings/RECn.pda across 8 slots, and appear in the sample picker alongside the bundled drum samples. They are saved in Playdate's own .pda format because the SDK cannot read back the WAV files it writes.

Drum pattern lanes

Below the six drum rows the editor has two value lanes. On either lane, A alone toggles a flag and A + up/down changes the value:

Lane	A	A + up/down
Velocity	accent on/off (boosts the step by 25%)	step velocity
Chance	step on/off (a muted step plays nothing)	probability the step fires

Behavior

Save and load project data on JSON file.

Development

Build the Playdate bundle:

pdc Source Output.pdx

Run the smoke tests:

for t in tests/*.lua; do lua "$t" || break; done

The bundled drum sounds in Source/Samples are original procedural samples made without third-party recordings.

Project JSON files contain a formatVersion field. Files created before this field was introduced are treated as format version 1.

The optional USB serial MIDI bridge accepts text commands through the Playdate serial message interface. Incoming drum notes are matched against the drum note map on the Preferences page:

note CHANNEL NOTE VELOCITY [LENGTH]
drum NOTE VELOCITY
start
continue
stop
clock

License

Source Code

The source code is licensed under the GNU General Public License v3.0 - see the LICENSE file for details.

UI Graphics and Assets

All UI graphics and visual assets are licensed under Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0). This means you are free to:

• Share — copy and redistribute the material in any medium or format
• Adapt — remix, transform, and build upon the material

Under the following terms:

• Attribution — You must give appropriate credit
• NonCommercial — You may not use the material for commercial purposes
• ShareAlike — If you remix, transform, or build upon the material, you must distribute your contributions under the same license

Fonts

• Cavs
• Nada
• Groria

The custom fonts used in this project were created by Leo Kuroshita and are licensed under the SIL Open Font License 1.1 (OFL-1.1). This means you are free to:

• Use the fonts in your own works
• Share and distribute the fonts
• Modify the fonts to create derivative works

Under the following terms:

• Attribution is required
• Modified fonts must be released under the same license
• The fonts cannot be sold by themselves, but may be bundled with software

Acknowledgments

Made by Leo Kuroshita from Hügelton Instrument. kobe, japan.

Disclaimer

This is a hobby project. While I've made it open source because I believe it might be valuable to others, the code may not be extensively documented. Feel free to explore and learn from it, but please understand its experimental nature.

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Note: This is a creative endeavor and the code structure reflects its organic development. While functional, it may not follow all best practices and could benefit from community improvements.