gion active
crgimenes vunknown added 2026-08-01 verified 2026-08-01
You need retro 8-bit sound effects and chiptune music for a game without shipping audio files — generate deterministic samples at runtime from a small seed-based recipe.
about
gion (擬音) is a chiptune/sfxr-style audio workbench and Go library for generating retro 8-bit sound effects and music. Rather than shipping WAV files, you author small deterministic parameter recipes in a .gion document (a Filo s-expression format); the same seed always produces the same samples on every platform. It can render at runtime (under a millisecond for effects, a few dozen milliseconds for music loops) or bake WAVs at build time via the gion-render CLI.
The interactive workbench lets you sculpt effects across seven families (pickup, laser, explosion, powerup, hit, jump, blip) with controls for waveform, envelope, frequency slide, vibrato, arpeggio, low-pass, and bit crush. Music generates perfectly-looping chiptune tracks across six moods (upbeat, heroic, dark, chill, battle, boss) with per-instrument mixer and mute switches. A 3D spectral waterfall updates live as you drag sliders; a plain 2D waveform view is also available.
The Go library API lets you load a .gion document and render effect parameters to []int16 samples. gion.Mutate derives slightly varied siblings of an effect from a seed, preventing repeated identical sound playback with zero asset overhead. Built on Ebitengine; a browser-based workbench is also available. Not a port of sfxr — written from scratch in Go.
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