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))
)

Current Scope

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.

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.