Update audio renderer to REV12: Add support for splitter biquad filter (#6813)

* Update audio renderer to REV12: Add support for splitter biquad filter

* Formatting

* Official names

* Update BiquadFilterState size + other fixes

* Update tests

* Update comment for version 2

* Size test for SplitterDestinationVersion2

* Should use Volume1 if no ramp

5 files changed, 288 insertions, 6 deletions

diff --git a/src/Ryujinx.Audio/Renderer/Dsp/Command/BiquadFilterAndMixCommand.cs b/src/Ryujinx.Audio/Renderer/Dsp/Command/BiquadFilterAndMixCommand.cs
new file mode 100644
index 00000000..106fc035
--- /dev/null
+++ b/src/Ryujinx.Audio/Renderer/Dsp/Command/BiquadFilterAndMixCommand.cs
@@ -0,0 +1,123 @@
+using Ryujinx.Audio.Renderer.Common;
+using Ryujinx.Audio.Renderer.Dsp.State;
+using Ryujinx.Audio.Renderer.Parameter;
+using System;
+
+namespace Ryujinx.Audio.Renderer.Dsp.Command
+{
+    public class BiquadFilterAndMixCommand : ICommand
+    {
+        public bool Enabled { get; set; }
+
+        public int NodeId { get; }
+
+        public CommandType CommandType => CommandType.BiquadFilterAndMix;
+
+        public uint EstimatedProcessingTime { get; set; }
+
+        public ushort InputBufferIndex { get; }
+        public ushort OutputBufferIndex { get; }
+
+        private BiquadFilterParameter _parameter;
+
+        public Memory<BiquadFilterState> BiquadFilterState { get; }
+        public Memory<BiquadFilterState> PreviousBiquadFilterState { get; }
+
+        public Memory<VoiceUpdateState> State { get; }
+
+        public int LastSampleIndex { get; }
+
+        public float Volume0 { get; }
+        public float Volume1 { get; }
+
+        public bool NeedInitialization { get; }
+        public bool HasVolumeRamp { get; }
+        public bool IsFirstMixBuffer { get; }
+
+        public BiquadFilterAndMixCommand(
+            float volume0,
+            float volume1,
+            uint inputBufferIndex,
+            uint outputBufferIndex,
+            int lastSampleIndex,
+            Memory<VoiceUpdateState> state,
+            ref BiquadFilterParameter filter,
+            Memory<BiquadFilterState> biquadFilterState,
+            Memory<BiquadFilterState> previousBiquadFilterState,
+            bool needInitialization,
+            bool hasVolumeRamp,
+            bool isFirstMixBuffer,
+            int nodeId)
+        {
+            Enabled = true;
+            NodeId = nodeId;
+
+            InputBufferIndex = (ushort)inputBufferIndex;
+            OutputBufferIndex = (ushort)outputBufferIndex;
+
+            _parameter = filter;
+            BiquadFilterState = biquadFilterState;
+            PreviousBiquadFilterState = previousBiquadFilterState;
+
+            State = state;
+            LastSampleIndex = lastSampleIndex;
+
+            Volume0 = volume0;
+            Volume1 = volume1;
+
+            NeedInitialization = needInitialization;
+            HasVolumeRamp = hasVolumeRamp;
+            IsFirstMixBuffer = isFirstMixBuffer;
+        }
+
+        public void Process(CommandList context)
+        {
+            ReadOnlySpan<float> inputBuffer = context.GetBuffer(InputBufferIndex);
+            Span<float> outputBuffer = context.GetBuffer(OutputBufferIndex);
+
+            if (NeedInitialization)
+            {
+                // If there is no previous state, initialize to zero.
+
+                BiquadFilterState.Span[0] = new BiquadFilterState();
+            }
+            else if (IsFirstMixBuffer)
+            {
+                // This is the first buffer, set previous state to current state.
+
+                PreviousBiquadFilterState.Span[0] = BiquadFilterState.Span[0];
+            }
+            else
+            {
+                // Rewind the current state by copying back the previous state.
+
+                BiquadFilterState.Span[0] = PreviousBiquadFilterState.Span[0];
+            }
+
+            if (HasVolumeRamp)
+            {
+                float volume = Volume0;
+                float ramp = (Volume1 - Volume0) / (int)context.SampleCount;
+
+                State.Span[0].LastSamples[LastSampleIndex] = BiquadFilterHelper.ProcessBiquadFilterAndMixRamp(
+                    ref _parameter,
+                    ref BiquadFilterState.Span[0],
+                    outputBuffer,
+                    inputBuffer,
+                    context.SampleCount,
+                    volume,
+                    ramp);
+            }
+            else
+            {
+                BiquadFilterHelper.ProcessBiquadFilterAndMix(
+                    ref _parameter,
+                    ref BiquadFilterState.Span[0],
+                    outputBuffer,
+                    inputBuffer,
+                    context.SampleCount,
+                    Volume1);
+            }
+        }
+    }
+}
diff --git a/src/Ryujinx.Audio/Renderer/Dsp/Command/CommandType.cs b/src/Ryujinx.Audio/Renderer/Dsp/Command/CommandType.cs
index 098a04a0..de5c0ea2 100644
--- a/src/Ryujinx.Audio/Renderer/Dsp/Command/CommandType.cs
+++ b/src/Ryujinx.Audio/Renderer/Dsp/Command/CommandType.cs
@@ -30,8 +30,10 @@ namespace Ryujinx.Audio.Renderer.Dsp.Command
         CopyMixBuffer,
         LimiterVersion1,
         LimiterVersion2,
-        GroupedBiquadFilter,
+        MultiTapBiquadFilter,
         CaptureBuffer,
         Compressor,
+        BiquadFilterAndMix,
+        MultiTapBiquadFilterAndMix,
     }
 }
diff --git a/src/Ryujinx.Audio/Renderer/Dsp/Command/MixRampGroupedCommand.cs b/src/Ryujinx.Audio/Renderer/Dsp/Command/MixRampGroupedCommand.cs
index 3c7dd63b..41ac84c1 100644
--- a/src/Ryujinx.Audio/Renderer/Dsp/Command/MixRampGroupedCommand.cs
+++ b/src/Ryujinx.Audio/Renderer/Dsp/Command/MixRampGroupedCommand.cs
@@ -24,7 +24,14 @@ namespace Ryujinx.Audio.Renderer.Dsp.Command
 
         public Memory<VoiceUpdateState> State { get; }
 
-        public MixRampGroupedCommand(uint mixBufferCount, uint inputBufferIndex, uint outputBufferIndex, Span<float> volume0, Span<float> volume1, Memory<VoiceUpdateState> state, int nodeId)
+        public MixRampGroupedCommand(
+            uint mixBufferCount,
+            uint inputBufferIndex,
+            uint outputBufferIndex,
+            ReadOnlySpan<float> volume0,
+            ReadOnlySpan<float> volume1,
+            Memory<VoiceUpdateState> state,
+            int nodeId)
         {
             Enabled = true;
             MixBufferCount = mixBufferCount;
@@ -48,7 +55,12 @@ namespace Ryujinx.Audio.Renderer.Dsp.Command
         }
 
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        private static float ProcessMixRampGrouped(Span<float> outputBuffer, ReadOnlySpan<float> inputBuffer, float volume0, float volume1, int sampleCount)
+        private static float ProcessMixRampGrouped(
+            Span<float> outputBuffer,
+            ReadOnlySpan<float> inputBuffer,
+            float volume0,
+            float volume1,
+            int sampleCount)
         {
             float ramp = (volume1 - volume0) / sampleCount;
             float volume = volume0;
diff --git a/src/Ryujinx.Audio/Renderer/Dsp/Command/MultiTapBiquadFilterAndMixCommand.cs b/src/Ryujinx.Audio/Renderer/Dsp/Command/MultiTapBiquadFilterAndMixCommand.cs
new file mode 100644
index 00000000..e359371b
--- /dev/null
+++ b/src/Ryujinx.Audio/Renderer/Dsp/Command/MultiTapBiquadFilterAndMixCommand.cs
@@ -0,0 +1,145 @@
+using Ryujinx.Audio.Renderer.Common;
+using Ryujinx.Audio.Renderer.Dsp.State;
+using Ryujinx.Audio.Renderer.Parameter;
+using System;
+
+namespace Ryujinx.Audio.Renderer.Dsp.Command
+{
+    public class MultiTapBiquadFilterAndMixCommand : ICommand
+    {
+        public bool Enabled { get; set; }
+
+        public int NodeId { get; }
+
+        public CommandType CommandType => CommandType.MultiTapBiquadFilterAndMix;
+
+        public uint EstimatedProcessingTime { get; set; }
+
+        public ushort InputBufferIndex { get; }
+        public ushort OutputBufferIndex { get; }
+
+        private BiquadFilterParameter _parameter0;
+        private BiquadFilterParameter _parameter1;
+
+        public Memory<BiquadFilterState> BiquadFilterState0 { get; }
+        public Memory<BiquadFilterState> BiquadFilterState1 { get; }
+        public Memory<BiquadFilterState> PreviousBiquadFilterState0 { get; }
+        public Memory<BiquadFilterState> PreviousBiquadFilterState1 { get; }
+
+        public Memory<VoiceUpdateState> State { get; }
+
+        public int LastSampleIndex { get; }
+
+        public float Volume0 { get; }
+        public float Volume1 { get; }
+
+        public bool NeedInitialization0 { get; }
+        public bool NeedInitialization1 { get; }
+        public bool HasVolumeRamp { get; }
+        public bool IsFirstMixBuffer { get; }
+
+        public MultiTapBiquadFilterAndMixCommand(
+            float volume0,
+            float volume1,
+            uint inputBufferIndex,
+            uint outputBufferIndex,
+            int lastSampleIndex,
+            Memory<VoiceUpdateState> state,
+            ref BiquadFilterParameter filter0,
+            ref BiquadFilterParameter filter1,
+            Memory<BiquadFilterState> biquadFilterState0,
+            Memory<BiquadFilterState> biquadFilterState1,
+            Memory<BiquadFilterState> previousBiquadFilterState0,
+            Memory<BiquadFilterState> previousBiquadFilterState1,
+            bool needInitialization0,
+            bool needInitialization1,
+            bool hasVolumeRamp,
+            bool isFirstMixBuffer,
+            int nodeId)
+        {
+            Enabled = true;
+            NodeId = nodeId;
+
+            InputBufferIndex = (ushort)inputBufferIndex;
+            OutputBufferIndex = (ushort)outputBufferIndex;
+
+            _parameter0 = filter0;
+            _parameter1 = filter1;
+            BiquadFilterState0 = biquadFilterState0;
+            BiquadFilterState1 = biquadFilterState1;
+            PreviousBiquadFilterState0 = previousBiquadFilterState0;
+            PreviousBiquadFilterState1 = previousBiquadFilterState1;
+
+            State = state;
+            LastSampleIndex = lastSampleIndex;
+
+            Volume0 = volume0;
+            Volume1 = volume1;
+
+            NeedInitialization0 = needInitialization0;
+            NeedInitialization1 = needInitialization1;
+            HasVolumeRamp = hasVolumeRamp;
+            IsFirstMixBuffer = isFirstMixBuffer;
+        }
+
+        private void UpdateState(Memory<BiquadFilterState> state, Memory<BiquadFilterState> previousState, bool needInitialization)
+        {
+            if (needInitialization)
+            {
+                // If there is no previous state, initialize to zero.
+
+                state.Span[0] = new BiquadFilterState();
+            }
+            else if (IsFirstMixBuffer)
+            {
+                // This is the first buffer, set previous state to current state.
+
+                previousState.Span[0] = state.Span[0];
+            }
+            else
+            {
+                // Rewind the current state by copying back the previous state.
+
+                state.Span[0] = previousState.Span[0];
+            }
+        }
+
+        public void Process(CommandList context)
+        {
+            ReadOnlySpan<float> inputBuffer = context.GetBuffer(InputBufferIndex);
+            Span<float> outputBuffer = context.GetBuffer(OutputBufferIndex);
+
+            UpdateState(BiquadFilterState0, PreviousBiquadFilterState0, NeedInitialization0);
+            UpdateState(BiquadFilterState1, PreviousBiquadFilterState1, NeedInitialization1);
+
+            if (HasVolumeRamp)
+            {
+                float volume = Volume0;
+                float ramp = (Volume1 - Volume0) / (int)context.SampleCount;
+
+                State.Span[0].LastSamples[LastSampleIndex] = BiquadFilterHelper.ProcessDoubleBiquadFilterAndMixRamp(
+                    ref _parameter0,
+                    ref _parameter1,
+                    ref BiquadFilterState0.Span[0],
+                    ref BiquadFilterState1.Span[0],
+                    outputBuffer,
+                    inputBuffer,
+                    context.SampleCount,
+                    volume,
+                    ramp);
+            }
+            else
+            {
+                BiquadFilterHelper.ProcessDoubleBiquadFilterAndMix(
+                    ref _parameter0,
+                    ref _parameter1,
+                    ref BiquadFilterState0.Span[0],
+                    ref BiquadFilterState1.Span[0],
+                    outputBuffer,
+                    inputBuffer,
+                    context.SampleCount,
+                    Volume1);
+            }
+        }
+    }
+}
diff --git a/src/Ryujinx.Audio/Renderer/Dsp/Command/GroupedBiquadFilterCommand.cs b/src/Ryujinx.Audio/Renderer/Dsp/Command/MultiTapBiquadFilterCommand.cs
index 7af851bd..e159f8ef 100644
--- a/src/Ryujinx.Audio/Renderer/Dsp/Command/GroupedBiquadFilterCommand.cs
+++ b/src/Ryujinx.Audio/Renderer/Dsp/Command/MultiTapBiquadFilterCommand.cs
@@ -4,13 +4,13 @@ using System;
 
 namespace Ryujinx.Audio.Renderer.Dsp.Command
 {
-    public class GroupedBiquadFilterCommand : ICommand
+    public class MultiTapBiquadFilterCommand : ICommand
     {
         public bool Enabled { get; set; }
 
         public int NodeId { get; }
 
-        public CommandType CommandType => CommandType.GroupedBiquadFilter;
+        public CommandType CommandType => CommandType.MultiTapBiquadFilter;
 
         public uint EstimatedProcessingTime { get; set; }
 
@@ -20,7 +20,7 @@ namespace Ryujinx.Audio.Renderer.Dsp.Command
         private readonly int _outputBufferIndex;
         private readonly bool[] _isInitialized;
 
-        public GroupedBiquadFilterCommand(int baseIndex, ReadOnlySpan<BiquadFilterParameter> filters, Memory<BiquadFilterState> biquadFilterStateMemory, int inputBufferOffset, int outputBufferOffset, ReadOnlySpan<bool> isInitialized, int nodeId)
+        public MultiTapBiquadFilterCommand(int baseIndex, ReadOnlySpan<BiquadFilterParameter> filters, Memory<BiquadFilterState> biquadFilterStateMemory, int inputBufferOffset, int outputBufferOffset, ReadOnlySpan<bool> isInitialized, int nodeId)
         {
             _parameters = filters.ToArray();
             _biquadFilterStates = biquadFilterStateMemory;