/godot-audio-systems

Music transitions and ducking

Crossfade (never hard-cut)

func crossfade_to(next_track: AudioStreamPlayer, fade := 2.0) -> void:
    next_track.stream = new_stream
    next_track.volume_db = -80.0
    next_track.play()
    var tween := create_tween().set_parallel(true)
    tween.tween_property(current_track, "volume_db", -80.0, fade)
    tween.tween_property(next_track, "volume_db", 0.0, fade)
    await tween.finished
    current_track.stop()
    current_track = next_track

Prefer Tween crossfades (0.5–2.0s). Abrupt stop()/play() breaks immersion.

BPM-aligned handoff

var beat_duration := 60.0 / bpm
var pos := current_track.get_playback_position()
var wait := beat_duration - fmod(pos, beat_duration)
await get_tree().create_timer(wait).timeout
crossfade_to(next_stream)

Dialogue ducking

Sidechain Music bus down while Voice plays — audio_bus_ducker_logic.gd. Route VO to Voice bus, not SFX.

Vertical stems (AudioStreamSynchronized)

Fade with set_sync_stream_volume(index, db) over 1–2s Tweens driven by a 0–1 intensity signal — audio_interactive_music_manager.gd. Deep rules: interactive-music-deep-dive.md.

Horizontal clips (AudioStreamInteractive)

Combat ↔ explore transitions on bar boundaries — interactive_music_graph.gd.

Subtitle sync (no timer drift)

pos = get_playback_position()
    + AudioServer.get_time_since_last_mix()
    - AudioServer.get_output_latency()

Implemented in subtitle_sync_system.gd. Method/Audio tracks in godot-animation-player for frame-locked VO.

Variation

pitch_scale = randf_range(0.9, 1.1) on repeated footsteps/gunshots so identical samples do not phase-stack.

Runtime bus FX

Reverb/low-pass on SFX bus for underwater or room zones — audio_environmental_reverb_zone.gd. Occlusion via ray + attenuation_filter_cutoff_hz — audio_occlusion_raycast.gd.