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, 103 insertions, 0 deletions

diff --git a/Ryujinx.Audio/Renderer/Parameter/EffectInParameter.cs b/Ryujinx.Audio/Renderer/Parameter/EffectInParameter.cs
new file mode 100644
index 00000000..af8edeff
--- /dev/null
+++ b/Ryujinx.Audio/Renderer/Parameter/EffectInParameter.cs
@@ -0,0 +1,103 @@
+//
+// 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 Ryujinx.Audio.Renderer.Common;
+using Ryujinx.Common.Utilities;
+using System;
+using System.Runtime.InteropServices;
+
+namespace Ryujinx.Audio.Renderer.Parameter
+{
+    /// <summary>
+    /// Input information for an effect.
+    /// </summary>
+    [StructLayout(LayoutKind.Sequential, Pack = 1)]
+    public struct EffectInParameter
+    {
+        /// <summary>
+        /// Type of the effect.
+        /// </summary>
+        public EffectType Type;
+
+        /// <summary>
+        /// Set to true if the effect is new.
+        /// </summary>
+        [MarshalAs(UnmanagedType.I1)]
+        public bool IsNew;
+
+        /// <summary>
+        /// Set to true if the effect must be active.
+        /// </summary>
+        [MarshalAs(UnmanagedType.I1)]
+        public bool IsEnabled;
+
+        /// <summary>
+        /// Reserved/padding.
+        /// </summary>
+        private byte _reserved1;
+
+        /// <summary>
+        /// The target mix id of the effect.
+        /// </summary>
+        public int MixId;
+
+        /// <summary>
+        /// Address of the processing workbuffer.
+        /// </summary>
+        /// <remarks>This is additional data that could be required by the effect processing.</remarks>
+        public ulong BufferBase;
+
+        /// <summary>
+        /// Size of the processing workbuffer.
+        /// </summary>
+        /// <remarks>This is additional data that could be required by the effect processing.</remarks>
+        public ulong BufferSize;
+
+        /// <summary>
+        /// Position of the effect while processing effects.
+        /// </summary>
+        public uint ProcessingOrder;
+
+        /// <summary>
+        /// Reserved/padding.
+        /// </summary>
+        private uint _reserved2;
+
+        /// <summary>
+        /// Specific data storage.
+        /// </summary>
+        private SpecificDataStruct _specificDataStart;
+
+        [StructLayout(LayoutKind.Sequential, Size = 0xA0, Pack = 1)]
+        private struct SpecificDataStruct { }
+
+        /// <summary>
+        /// Specific data changing depending of the <see cref="Type"/>. See also the <see cref="Effect"/> namespace.
+        /// </summary>
+        public Span<byte> SpecificData => SpanHelpers.AsSpan<SpecificDataStruct, byte>(ref _specificDataStart);
+
+        /// <summary>
+        ///  Check if the given channel count is valid.
+        /// </summary>
+        /// <param name="channelCount">The channel count to check</param>
+        /// <returns>Returns true if the channel count is valid.</returns>
+        public static bool IsChannelCountValid(int channelCount)
+        {
+            return channelCount == 1 || channelCount == 2 || channelCount == 4 || channelCount == 6;
+        }
+    }
+}