whammy pitch shift in bass (YARC-Official#487) (YARC-Official#499)

Co-authored-by: RileyTheFox <[email protected]>

Assets/Script/Audio/Bass/BassAudioManager.cs

@@ -31,6 +31,9 @@ public class BassAudioManager : MonoBehaviour, IAudioManager {
 		public float CurrentPositionF => (float) GetPosition();
 		public float AudioLengthF { get; private set; }
 
+		[Range(0, 1)]
+		public float whammyPitchPercent;
+
 		public event Action SongEnd {
 			add {
 				if (_mixer is null) {
@@ -55,6 +58,15 @@ public event Action SongEnd {
 
 		private IStemMixer _mixer;
 
+		private void Update() {
+			if (_mixer is null || _mixer.Channels.Count == 0) {
+				return;
+			}
+
+			foreach (var channel in _mixer.Channels) {
+				channel.Value.SetWhammyPitch(whammyPitchPercent);
+			}
+		}
 
 		private void Awake() {
 			SupportedFormats = new[] {

Assets/Script/Audio/Bass/BassMoggStemChannel.cs

@@ -112,6 +112,12 @@ public void SetReverb(bool reverb) {
 			}
 		}
 
+		public void SetWhammyPitch(float percent) {
+			foreach (var channel in _channels) {
+				channel.SetWhammyPitch(percent);
+			}
+		}
+
 		public double GetPosition() {
 			return _leadChannel.GetPosition();
 		}

Assets/Script/Audio/Bass/BassStemChannel.cs

@@ -54,9 +54,23 @@ public event Action ChannelEnd {
 
 		private int _sourceHandle;
 
+		private int _pitchFxHandle;
+		private int _pitchFxReverbHandle;
+
 		private bool _isReverbing;
 		private bool _disposed;
 
+#if UNITY_EDITOR_WIN || UNITY_STANDALONE_WIN
+		private PitchShiftWindowsParameters _pitchParams = new() {
+#else
+		private PitchShiftParameters _pitchParams = new() {
+#endif
+			fPitchShift = 1,
+			fSemitones = 0,
+			lFFTsize = 2048,
+			lOsamp = 32,
+		};
+
 		public BassStemChannel(IAudioManager manager, string path, SongStem stem) {
 			_manager = manager;
 			_path = path;
@@ -134,6 +148,18 @@ public int Load(float speed) {
 			Bass.ChannelSetAttribute(StreamHandle, ChannelAttribute.Volume, _manager.GetVolumeSetting(Stem));
 			Bass.ChannelSetAttribute(ReverbStreamHandle, ChannelAttribute.Volume, 0);
 
+			_pitchFxHandle = Bass.ChannelSetFX(StreamHandle, EffectType.PitchShift, 0);
+
+			if (_pitchFxHandle == 0) {
+				Debug.LogError("Failed to add pitchshift: " + Bass.LastError);
+			}
+
+			_pitchFxReverbHandle = Bass.ChannelSetFX(ReverbStreamHandle, EffectType.PitchShift, 0);
+
+			if (_pitchFxReverbHandle == 0) {
+				Debug.LogError("Failed to add pitchshift: " + Bass.LastError);
+			}
+
 			if (!Mathf.Approximately(speed, 1f)) {
 				// Gets relative speed from 100% (so 1.05f = 5% increase)
 				float percentageSpeed = Math.Abs(speed) * 100;
@@ -249,6 +275,37 @@ public void SetReverb(bool reverb) {
 			}
 		}
 
+		private float lastShift;
+
+		public void SetWhammyPitch(float percent) {
+			if (Stem != SongStem.Guitar && Stem != SongStem.Bass && Stem != SongStem.Rhythm)
+				return;
+
+			percent = Mathf.Clamp(percent, 0f, 1f);
+
+			float shift = Mathf.Pow(2, (-2 * percent) / 12);
+
+			if (Math.Abs(shift - lastShift) < float.Epsilon) {
+				return;
+			}
+
+			lastShift = shift;
+
+			Debug.Log(shift);
+
+			_pitchParams.fPitchShift = shift;
+
+			Debug.Log(_pitchFxHandle);
+
+			if (!Bass.FXSetParameters(_pitchFxHandle, _pitchParams)) {
+				Debug.LogError("Failed to set params (normal fx): " + Bass.LastError);
+			}
+
+			if (!Bass.FXSetParameters(_pitchFxReverbHandle, _pitchParams)) {
+				Debug.LogError("Failed to set params (reverb fx): " + Bass.LastError);
+			}
+		}
+
 		public double GetPosition() {
 			return Bass.ChannelBytes2Seconds(StreamHandle, Bass.ChannelGetPosition(StreamHandle));
 		}

Assets/Script/Audio/Bass/PitchShiftWindowsParameters.cs

@@ -0,0 +1,41 @@
+using System.Runtime.InteropServices;
+using ManagedBass;
+
+/// <summary>
+/// Parameters for PitchShift Effect.
+/// </summary>
+[StructLayout(LayoutKind.Sequential)]
+public class PitchShiftWindowsParameters : IEffectParameter
+{
+	/// <summary>
+	/// A factor value which is between 0.5 (one octave down) and 2 (one octave up) (1 won't change the pitch, default).
+	/// </summary>
+	public float fPitchShift;
+
+	/// <summary>
+	/// Semitones (0 won't change the pitch). Default = 0.
+	/// </summary>
+	public float fSemitones;
+
+	/// <summary>
+	/// Defines the FFT frame size used for the processing. Typical values are 1024, 2048 (default) and 4096, max is 8192.
+	/// </summary>
+	/// <remarks>It may be any value up to 8192 but it MUST be a power of 2.</remarks>
+	public int lFFTsize;
+
+	/// <summary>
+	/// Is the STFT oversampling factor which also determines the overlap between adjacent STFT frames. Default = 8.
+	/// </summary>
+	/// <remarks>It should at least be 4 for moderate scaling ratios. A value of 32 is recommended for best quality (better quality = higher CPU usage).</remarks>
+	public int lOsamp;
+
+	/// <summary>
+	/// A <see cref="FXChannelFlags" /> flag to define on which channels to apply the effect. Default: <see cref="FXChannelFlags.All"/>
+	/// </summary>
+	public FXChannelFlags lChannel = FXChannelFlags.All;
+
+	/// <summary>
+	/// Gets the <see cref="EffectType"/>.
+	/// </summary>
+	public EffectType FXType => EffectType.PitchShift;
+}

Assets/Script/Audio/Interfaces/IStemChannel.cs

@@ -21,6 +21,8 @@ public interface IStemChannel : IDisposable {
 
 		public void SetReverb(bool reverb);
 
+		public void SetWhammyPitch(float percent);
+
 		public double GetPosition();
 		public void SetPosition(double position);