4 files changed, 302 insertions, 0 deletions
diff --git a/Ryujinx.Audio.Renderer/Dsp/Effect/DecayDelay.cs b/Ryujinx.Audio.Renderer/Dsp/Effect/DecayDelay.cs
new file mode 100644
index 00000000..6d885dbf
--- /dev/null
+++ b/Ryujinx.Audio.Renderer/Dsp/Effect/DecayDelay.cs
@@ -0,0 +1,69 @@
+//
+// Copyright (c) 2019-2020 Ryujinx
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+//
+
+namespace Ryujinx.Audio.Renderer.Dsp.Effect
+{
+    public class DecayDelay : IDelayLine
+    {
+        private readonly IDelayLine _delayLine;
+
+        public uint CurrentSampleCount => _delayLine.CurrentSampleCount;
+
+        public uint SampleCountMax => _delayLine.SampleCountMax;
+
+        private float _decayRate;
+
+        public DecayDelay(IDelayLine delayLine)
+        {
+            _decayRate = 0.0f;
+            _delayLine = delayLine;
+        }
+
+        public void SetDecayRate(float decayRate)
+        {
+            _decayRate = decayRate;
+        }
+
+        public float Update(float value)
+        {
+            float delayLineValue = _delayLine.Read();
+            float processedValue = value - (_decayRate * delayLineValue);
+
+            return _delayLine.Update(processedValue) + processedValue * _decayRate;
+        }
+
+        public void SetDelay(float delayTime)
+        {
+            _delayLine.SetDelay(delayTime);
+        }
+
+        public float Read()
+        {
+            return _delayLine.Read();
+        }
+
+        public float TapUnsafe(uint sampleIndex, int offset)
+        {
+            return _delayLine.TapUnsafe(sampleIndex, offset);
+        }
+
+        public float Tap(uint sampleIndex)
+        {
+            return _delayLine.Tap(sampleIndex);
+        }
+    }
+}
diff --git a/Ryujinx.Audio.Renderer/Dsp/Effect/DelayLine.cs b/Ryujinx.Audio.Renderer/Dsp/Effect/DelayLine.cs
new file mode 100644
index 00000000..b443cd15
--- /dev/null
+++ b/Ryujinx.Audio.Renderer/Dsp/Effect/DelayLine.cs
@@ -0,0 +1,87 @@
+//
+// Copyright (c) 2019-2020 Ryujinx
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+//
+
+using System;
+
+namespace Ryujinx.Audio.Renderer.Dsp.Effect
+{
+    public class DelayLine : IDelayLine
+    {
+        private float[] _workBuffer;
+        private uint _sampleRate;
+        private uint _currentSampleIndex;
+        private uint _lastSampleIndex;
+
+        public uint CurrentSampleCount { get; private set; }
+        public uint SampleCountMax { get; private set; }
+
+        public DelayLine(uint sampleRate, float delayTimeMax)
+        {
+            _sampleRate = sampleRate;
+            SampleCountMax = IDelayLine.GetSampleCount(_sampleRate, delayTimeMax);
+            _workBuffer = new float[SampleCountMax];
+
+            SetDelay(delayTimeMax);
+        }
+
+        private void ConfigureDelay(uint targetSampleCount)
+        {
+            CurrentSampleCount = Math.Min(SampleCountMax, targetSampleCount);
+            _currentSampleIndex = 0;
+            _lastSampleIndex = CurrentSampleCount - 1;
+        }
+
+        public void SetDelay(float delayTime)
+        {
+            ConfigureDelay(IDelayLine.GetSampleCount(_sampleRate, delayTime));
+        }
+
+        public float Read()
+        {
+            return _workBuffer[_currentSampleIndex];
+        }
+
+        public float Update(float value)
+        {
+            float output = Read();
+
+            _workBuffer[_currentSampleIndex++] = value;
+
+            if (_currentSampleIndex >= _lastSampleIndex)
+            {
+                _currentSampleIndex = 0;
+            }
+
+            return output;
+        }
+
+        public float TapUnsafe(uint sampleIndex, int offset)
+        {
+            return IDelayLine.Tap(_workBuffer, (int)_currentSampleIndex, (int)sampleIndex + offset, (int)CurrentSampleCount);
+        }
+
+        public float Tap(uint sampleIndex)
+        {
+            if (sampleIndex >= CurrentSampleCount)
+            {
+                sampleIndex = CurrentSampleCount - 1;
+            }
+
+            return TapUnsafe(sampleIndex, -1);
+        }
+    }
+}
diff --git a/Ryujinx.Audio.Renderer/Dsp/Effect/DelayLineReverb3d.cs b/Ryujinx.Audio.Renderer/Dsp/Effect/DelayLineReverb3d.cs
new file mode 100644
index 00000000..acdfdb4f
--- /dev/null
+++ b/Ryujinx.Audio.Renderer/Dsp/Effect/DelayLineReverb3d.cs
@@ -0,0 +1,93 @@
+//
+// Copyright (c) 2019-2020 Ryujinx
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+//
+
+using System.Diagnostics;
+
+namespace Ryujinx.Audio.Renderer.Dsp.Effect
+{
+    public class DelayLine3d : IDelayLine
+    {
+        private float[] _workBuffer;
+        private uint _sampleRate;
+        private uint _currentSampleIndex;
+        private uint _lastSampleIndex;
+
+        public uint CurrentSampleCount { get; private set; }
+        public uint SampleCountMax { get; private set; }
+
+        public DelayLine3d(uint sampleRate, float delayTimeMax)
+        {
+            _sampleRate = sampleRate;
+            SampleCountMax = IDelayLine.GetSampleCount(_sampleRate, delayTimeMax);
+            _workBuffer = new float[SampleCountMax + 1];
+
+            SetDelay(delayTimeMax);
+        }
+
+        private void ConfigureDelay(uint targetSampleCount)
+        {
+            if (SampleCountMax >= targetSampleCount)
+            {
+                CurrentSampleCount = targetSampleCount;
+                _lastSampleIndex = (_currentSampleIndex + targetSampleCount) % (SampleCountMax + 1);
+            }
+        }
+
+        public void SetDelay(float delayTime)
+        {
+            ConfigureDelay(IDelayLine.GetSampleCount(_sampleRate, delayTime));
+        }
+
+        public float Read()
+        {
+            return _workBuffer[_currentSampleIndex];
+        }
+
+        public float Update(float value)
+        {
+            Debug.Assert(!float.IsNaN(value) && !float.IsInfinity(value));
+
+            _workBuffer[_lastSampleIndex++] = value;
+
+            float output = Read();
+
+            _currentSampleIndex++;
+
+            if (_currentSampleIndex >= SampleCountMax)
+            {
+                _currentSampleIndex = 0;
+            }
+
+            if (_lastSampleIndex >= SampleCountMax)
+            {
+                _lastSampleIndex = 0;
+            }
+
+            return output;
+        }
+
+        public float TapUnsafe(uint sampleIndex, int offset)
+        {
+            return IDelayLine.Tap(_workBuffer, (int)_lastSampleIndex, (int)sampleIndex + offset, (int)SampleCountMax + 1);
+        }
+
+        public float Tap(uint sampleIndex)
+        {
+            return TapUnsafe(sampleIndex, -1);
+        }
+    }
+}
diff --git a/Ryujinx.Audio.Renderer/Dsp/Effect/IDelayLine.cs b/Ryujinx.Audio.Renderer/Dsp/Effect/IDelayLine.cs
new file mode 100644
index 00000000..d44f5596
--- /dev/null
+++ b/Ryujinx.Audio.Renderer/Dsp/Effect/IDelayLine.cs
@@ -0,0 +1,53 @@
+//
+// Copyright (c) 2019-2020 Ryujinx
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+//
+
+using System;
+using System.Runtime.CompilerServices;
+
+namespace Ryujinx.Audio.Renderer.Dsp.Effect
+{
+    public interface IDelayLine
+    {
+        uint CurrentSampleCount { get; }
+        uint SampleCountMax { get; }
+
+        void SetDelay(float delayTime);
+        float Read();
+        float Update(float value);
+
+        float TapUnsafe(uint sampleIndex, int offset);
+        float Tap(uint sampleIndex);
+
+        public static float Tap(Span<float> workBuffer, int baseIndex, int sampleIndex, int delaySampleCount)
+        {
+            int targetIndex = baseIndex - sampleIndex;
+
+            if (targetIndex < 0)
+            {
+                targetIndex += delaySampleCount;
+            }
+
+            return workBuffer[targetIndex];
+        }
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static uint GetSampleCount(uint sampleRate, float delayTime)
+        {
+            return (uint)MathF.Round(sampleRate * delayTime);
+        }
+    }
+}