Runtime WAV Loading (AudioClip from disk)

When a code-only 7DTD mod needs a sampled sound but can't rebuild its Unity asset bundle (.unity3d), you can ship a loose .wav in the mod's Resources/ folder and decode it into an AudioClip at runtime — no bundle, no UnityWebRequest.

How

1. Ship the WAV in resources/ and copy it to <ModDest>/Resources/ in deploy.ps1 (same pattern as the goggles PNG in the FPV mod).
2. Resolve the deployed path via the mod instance path: ModInfo/Mod.Path (FPV exposes it as FPVModInit.ModPath), then Path.Combine(modPath, "Resources", "file.wav").
3. File.ReadAllBytes(path) → parse the RIFF/WAVE header → decode PCM into a float[] normalized to -1..1 → AudioClip.Create(name, samplesPerChannel, channels, sampleRate, false) then clip.SetData(data, 0).

WAV parsing notes

• Walk the chunk list (4-byte id + 4-byte little-endian size + payload); don't assume fmt is immediately followed by data — extra chunks (LIST, etc.) can sit between them. Chunks are word-aligned: an odd size has a pad byte.
• fmt fields: audioFormat(2) must be 1 (uncompressed PCM), channels(2), sampleRate(4), then bitsPerSample at offset +14.
• Decode per bit depth: 8-bit is unsigned (0..255, centre 128); 16/24/32-bit are signed little-endian. 24-bit needs manual sign extension.
• AudioClip.Create takes samples per channel (not total interleaved samples); SetData takes the full interleaved float[].
• Reference implementation: FPV/src/FPVWavLoader.cs.

MP3/other compressed sources

The loader is PCM-WAV-only by design — don't try to decode MP3 in managed code. Convert once at authoring time and ship the WAV: ffmpeg -i input.mp3 -ac 1 -ar 44100 -acodec pcm_s16le output.wav (ffmpeg is installed via chocolatey on this machine). Keep the original MP3 in resources/ as the source of truth; only the WAV is deployed. Example: the FPV mod's Betaflight startup melody (betaflight_startup.mp3 → betaflight-startup.wav).

Applies when

Any mod that wants recorded audio without an asset-bundle round-trip. Same runtime-AudioClip path the FPV mod already uses for its synthesized rotor sounds — this just fills the buffer from a file instead of a synth. For the synth side (RPM→pitch model, anti-rasp spectral tuning), see Synthesized Drone Rotor Audio. sounds ([[Procedural Engine-Rotor Loop Synthesis]]) — this just fills the buffer from a file instead of a synth.