Sdl backend (#670)

* [audio] added sdl audio backend and in-tree atrac9 decoder * [input] replaced per-platform pad readers with sdl gamepad input * [video] added sdl window and host display plumbing * [gui] added host display options and per-game render settings * [bink] synced host movie playback to the guest audio clock * [cpu] hooked windows write faults into guest image tracking * [perf] added guest and render profiling, reserved host cpu lanes * [kernel] fixed stale pthread mutex handle alias * [host] wired the sdl session, save-data paths and project references * [audio] hoisted ajm trace stackalloc out of its loop * [video] Add guest image sync setting * [build] Strip native symbols * reuse
2026-07-31 23:19:44 +08:00 · 2026-07-28 03:33:26 +03:00
parent b4cc5f88ca
commit 2b6bd5a532
111 changed files with 9846 additions and 4479 deletions
@@ -0,0 +1,121 @@
+// SPDX-License-Identifier: MIT
+#nullable disable
+using System.IO;
+using LibAtrac9.Utilities;
+
+namespace LibAtrac9
+{
+    /// <summary>
+    /// Stores the configuration data needed to decode or encode an ATRAC9 stream.
+    /// </summary>
+    public class Atrac9Config
+    {
+        /// <summary>
+        /// The 4-byte ATRAC9 configuration data.
+        /// </summary>
+        public byte[] ConfigData { get; }
+
+        /// <summary>
+        /// A 4-bit value specifying one of 16 sample rates.
+        /// </summary>
+        public int SampleRateIndex { get; }
+        /// <summary>
+        /// A 3-bit value specifying one of 6 substream channel mappings.
+        /// </summary>
+        public int ChannelConfigIndex { get; }
+        /// <summary>
+        /// An 11-bit value containing the average size of a single frame.
+        /// </summary>
+        public int FrameBytes { get; }
+        /// <summary>
+        /// A 2-bit value indicating how many frames are in each superframe.
+        /// </summary>
+        public int SuperframeIndex { get; }
+
+        /// <summary>
+        /// The channel mapping used by the ATRAC9 stream.
+        /// </summary>
+        public ChannelConfig ChannelConfig { get; }
+        /// <summary>
+        /// The total number of channels in the ATRAC9 stream.
+        /// </summary>
+        public int ChannelCount { get; }
+        /// <summary>
+        /// The sample rate of the ATRAC9 stream.
+        /// </summary>
+        public int SampleRate { get; }
+        /// <summary>
+        /// Indicates whether the ATRAC9 stream has a <see cref="SampleRateIndex"/> of 8 or above.
+        /// </summary>
+        public bool HighSampleRate { get; }
+
+        /// <summary>
+        /// The number of frames in each superframe.
+        /// </summary>
+        public int FramesPerSuperframe { get; }
+        /// <summary>
+        /// The number of samples in one frame as an exponent of 2.
+        /// <see cref="FrameSamples"/> = 2^<see cref="FrameSamplesPower"/>.
+        /// </summary>
+        public int FrameSamplesPower { get; }
+        /// <summary>
+        /// The number of samples in one frame.
+        /// </summary>
+        public int FrameSamples { get; }
+        /// <summary>
+        /// The number of bytes in one superframe.
+        /// </summary>
+        public int SuperframeBytes { get; }
+        /// <summary>
+        /// The number of samples in one superframe.
+        /// </summary>
+        public int SuperframeSamples { get; }
+
+        /// <summary>
+        /// Reads ATRAC9 configuration data and calculates the stream parameters from it.
+        /// </summary>
+        /// <param name="configData">The processed ATRAC9 configuration.</param>
+        public Atrac9Config(byte[] configData)
+        {
+            if (configData == null || configData.Length != 4)
+            {
+                throw new InvalidDataException("Config data must be 4 bytes long");
+            }
+
+            ReadConfigData(configData, out int a, out int b, out int c, out int d);
+            SampleRateIndex = a;
+            ChannelConfigIndex = b;
+            FrameBytes = c;
+            SuperframeIndex = d;
+            ConfigData = configData;
+
+            FramesPerSuperframe = 1 << SuperframeIndex;
+            SuperframeBytes = FrameBytes << SuperframeIndex;
+            ChannelConfig = Tables.ChannelConfig[ChannelConfigIndex];
+
+            ChannelCount = ChannelConfig.ChannelCount;
+            SampleRate = Tables.SampleRates[SampleRateIndex];
+            HighSampleRate = SampleRateIndex > 7;
+            FrameSamplesPower = Tables.SamplingRateIndexToFrameSamplesPower[SampleRateIndex];
+            FrameSamples = 1 << FrameSamplesPower;
+            SuperframeSamples = FrameSamples * FramesPerSuperframe;
+        }
+
+        private static void ReadConfigData(byte[] configData, out int sampleRateIndex, out int channelConfigIndex, out int frameBytes, out int superframeIndex)
+        {
+            var reader = new BitReader(configData);
+
+            int header = reader.ReadInt(8);
+            sampleRateIndex = reader.ReadInt(4);
+            channelConfigIndex = reader.ReadInt(3);
+            int validationBit = reader.ReadInt(1);
+            frameBytes = reader.ReadInt(11) + 1;
+            superframeIndex = reader.ReadInt(2);
+
+            if (header != 0xFE || validationBit != 0)
+            {
+                throw new InvalidDataException("ATRAC9 Config Data is invalid");
+            }
+        }
+    }
+}