Haydn: Part 1 (#2007)

* Haydn: Part 1

Based on my reverse of audio 11.0.0.

As always, core implementation under LGPLv3 for the same reasons as for Amadeus.

This place the bases of a more flexible audio system while making audout & audin accurate.

This have the following improvements:
- Complete reimplementation of audout and audin.
- Audin currently only have a dummy backend.
- Dramatically reduce CPU usage by up to 50% in common cases (SoundIO and OpenAL).
- Audio Renderer now can output to 5.1 devices when supported.
- Audio Renderer init its backend on demand instead of keeping two up all the time.
- All backends implementation are now in their own project.
- Ryujinx.Audio.Renderer was renamed Ryujinx.Audio and was refactored because of this.

As a note, games having issues with OpenAL haven't improved and will not
because of OpenAL design (stopping when buffers finish playing causing
possible audio "pops" when buffers are very small).

* Update for latest hexkyz's edits on Switchbrew

* audren: Rollback channel configuration changes

* Address gdkchan's comments

* Fix typo in OpenAL backend driver

* Address last comments

* Fix a nit

* Address gdkchan's comments

1 files changed, 95 insertions, 0 deletions

diff --git a/Ryujinx.Audio/Renderer/Dsp/Effect/DelayLine.cs b/Ryujinx.Audio/Renderer/Dsp/Effect/DelayLine.cs
new file mode 100644
index 00000000..d178e699
--- /dev/null
+++ b/Ryujinx.Audio/Renderer/Dsp/Effect/DelayLine.cs
@@ -0,0 +1,95 @@
+//
+// Copyright (c) 2019-2021 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;
+
+            if (CurrentSampleCount == 0)
+            {
+                _lastSampleIndex = 0;
+            }
+            else
+            {
+                _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);
+        }
+    }
+}