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

Ryujinx.Audio/Renderer/Dsp/FloatingPointHelper.cs

@@ -0,0 +1,84 @@
+//
+// 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;
+using System.Runtime.CompilerServices;
+
+namespace Ryujinx.Audio.Renderer.Dsp
+{
+    public static class FloatingPointHelper
+    {
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static float MultiplyRoundDown(float a, float b)
+        {
+            return RoundDown(a * b);
+        }
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static float RoundDown(float a)
+        {
+            return MathF.Round(a, 0);
+        }
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static float RoundUp(float a)
+        {
+            return MathF.Round(a);
+        }
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static float MultiplyRoundUp(float a, float b)
+        {
+            return RoundUp(a * b);
+        }
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static float Pow10(float x)
+        {
+            // NOTE: Nintendo implementation uses Q15 and a LUT for this, we don't.
+            // As such, we support the same ranges as Nintendo to avoid unexpected behaviours.
+            if (x >= 0.0f)
+            {
+                return 1.0f;
+            }
+            else if (x <= -5.3f)
+            {
+                return 0.0f;
+            }
+
+            return MathF.Pow(10, x);
+        }
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static float DegreesToRadians(float degrees)
+        {
+            return degrees * MathF.PI / 180.0f;
+        }
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static float Cos(float value)
+        {
+            return MathF.Cos(DegreesToRadians(value));
+        }
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static float Sin(float value)
+        {
+            return MathF.Sin(DegreesToRadians(value));
+        }
+    }
+}