Ox0badf00d

Ox0badf00d is a native Swift tracker module package for loading and rendering classic module music.

The initial engine supports:

• ProTracker-style MOD files with 4/6/8+ channel signatures.
• FastTracker II XM files with packed pattern data, note-to-sample instrument maps, volume/panning envelopes, and delta-decoded 8/16-bit samples.
• Impulse Tracker IT files with packed pattern data and uncompressed PCM samples.
• Tick-based playback for core tracker effects: arpeggio, portamento, tone portamento, vibrato, tremolo, volume slides, panning, sample offsets, retrigger, note cut/delay, pattern break/jump, pattern delay, tempo/speed, and global volume changes.
• Streaming-style stereo Float PCM rendering with no libopenmpt, no ffmpeg, and no external decoder.
• Optional psychoacoustic 3D spatialization using interaural time differences, level differences, head-shadow filtering, crossfeed, and early reflection cues.

This is intentionally a Swift package rather than app-only code so SwiftBuilder can use it as the real playback core later.

import Foundation
import Ox0badf00d

let data = try Data(contentsOf: moduleURL)
let module = try ModuleLoader.load(data: data)
let renderer = ModuleRenderer(module: module, sampleRate: 44_100)
let pcm = renderer.renderSong(maxSeconds: 600, tailSeconds: 2)

PCMBuffer.interleavedSamples contains stereo samples in left/right order.

For spatial playback:

let renderer = ModuleRenderer(
    module: module,
    sampleRate: 44_100,
    options: RenderOptions(spatialization: .psychoacoustic3D(.spacious))
)

This is a real parser, tick scheduler, effect engine, and PCM renderer. The goal is capability parity with mature tracker players, then to go beyond them with modern spatial rendering.

We've now added a rendering module for Apple platforms that provides an AVAudioEngine session for your convenience. Feedback appreciated.

Still to do for that bar:

• Full Impulse Tracker (IT) playback. Only uncompressed IT samples decode today; a module can parse structurally yet render pure silence (see TrackerModule.isRenderable). Needed:
  • IT 2.14 compressed sample decoding — ITParser.parseSample currently returns an empty sample for the flags & 0x08 (compressed) path, so any IT relying on compression comes back silent.
  • Verify/repair IT packed-pattern decoding — a 982-byte size-coded 1kb.it decoded to zero note events, so patterns need a second look, not just samples.
  • Confirm the IT note range maps correctly: values are 0–119 (0 = C-0), but pitch(fromITNote:) starts its note case at 1, dropping C-0.
  • IT instrument envelope playback and New Note Actions.
• More exact XM envelope edge cases and fadeout behavior.
• More exact per-format effect memory and edge-case compatibility.
• Filter/resonance commands where formats provide them.
• Golden-file render tests against known-good tracker engines.