simple-zig-wasm-synthesizergaycodegal/simple-zig-wasm-synthesizer
building a wasm web audio api synthesizer using zig
README
Simple Wave Synthesizer
The intention of this project is to create a small (in code size) synthesizer to make bit tune sound effect / music for online games. This project is demonstrating compiling a polyphonic synthesizer in Zig and playing it from the web.
It is currently monophonic, but mostly usable.
Read the Write Up to learn how this was made.
Rationale
- Games can easily use megabytes for music even if the rest of the game is very small due to pixel art or being text based.
- mod / xm would be great, but its not a format suited for sound effects, only for music
- mod / xm don't allow instruments to use multiple samples
Could I have used wave files for sfx and xm for music? Definitely, but I didn't want to, as I had already seen what Tic80 could do.
Progress
In its current state, it could be used to play short sound effects for online games. The code size is at last check ~19.2kb in js + wasm (without shortening variable names etc), or 8.5kb zipped. The audio it generates is 45kb/s 8bit audio.
The wasm binary itself is only 3kb.
- Play different notes from a note bank
- Play different waveforms from a waveform bank
- Music player which doesn't suffer the length limitations of audiobuffer, instead using AudioWorklet
- Message passing setup for the music player to allow for dynamic choice of song
- Volume control via volume list
- technically, because volume now allows you to play less than at maximum amplitude, you can now do polyphony by just playing multiple things at once with low volume.
- can interrupt / resume at any point, meaning support for using a sfx as an instrument in a music track can be worked on now
Soon
- 4 track polyphony / maybe 8 track 4 volume, 4 sfx
Later
- Waveform editing
- Make music be able to use notes and sfx alike to play music (sfx as instruments)
- Make an optional file format for the music
Licenses
This project is MIT licensed, the only outside code it uses is the NoteHz taken from Tic80 (which is also MIT Licensed). There is a license file for a file called wavefile.js but that code is not included in this github, and I only use it for testing to verify the waveforms are correct, but if you choose to download that file yourself, you have the license.