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 06:59:45 +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 +1,142 @@
+// SPDX-License-Identifier: MIT
+#nullable disable
+using System;
+
+namespace LibAtrac9
+{
+    internal static class BitAllocation
+    {
+        public static void CreateGradient(Block block)
+        {
+            int valueCount = block.GradientEndValue - block.GradientStartValue;
+            int unitCount = block.GradientEndUnit - block.GradientStartUnit;
+
+            for (int i = 0; i < block.GradientEndUnit; i++)
+            {
+                block.Gradient[i] = block.GradientStartValue;
+            }
+
+            for (int i = block.GradientEndUnit; i <= block.QuantizationUnitCount; i++)
+            {
+                block.Gradient[i] = block.GradientEndValue;
+            }
+            if (unitCount <= 0) return;
+            if (valueCount == 0) return;
+
+            byte[] curve = Tables.GradientCurves[unitCount - 1];
+            if (valueCount <= 0)
+            {
+                double scale = (-valueCount - 1) / 31.0;
+                int baseVal = block.GradientStartValue - 1;
+                for (int i = block.GradientStartUnit; i < block.GradientEndUnit; i++)
+                {
+                    block.Gradient[i] = baseVal - (int)(curve[i - block.GradientStartUnit] * scale);
+                }
+            }
+            else
+            {
+                double scale = (valueCount - 1) / 31.0;
+                int baseVal = block.GradientStartValue + 1;
+                for (int i = block.GradientStartUnit; i < block.GradientEndUnit; i++)
+                {
+                    block.Gradient[i] = baseVal + (int)(curve[i - block.GradientStartUnit] * scale);
+                }
+            }
+        }
+
+        public static void CalculateMask(Channel channel)
+        {
+            Array.Clear(channel.PrecisionMask, 0, channel.PrecisionMask.Length);
+            for (int i = 1; i < channel.Block.QuantizationUnitCount; i++)
+            {
+                int delta = channel.ScaleFactors[i] - channel.ScaleFactors[i - 1];
+                if (delta > 1)
+                {
+                    channel.PrecisionMask[i] += Math.Min(delta - 1, 5);
+                }
+                else if (delta < -1)
+                {
+                    channel.PrecisionMask[i - 1] += Math.Min(delta * -1 - 1, 5);
+                }
+            }
+        }
+
+        public static void CalculatePrecisions(Channel channel)
+        {
+            Block block = channel.Block;
+
+            if (block.GradientMode != 0)
+            {
+                for (int i = 0; i < block.QuantizationUnitCount; i++)
+                {
+                    channel.Precisions[i] = channel.ScaleFactors[i] + channel.PrecisionMask[i] - block.Gradient[i];
+                    if (channel.Precisions[i] > 0)
+                    {
+                        switch (block.GradientMode)
+                        {
+                            case 1:
+                                channel.Precisions[i] /= 2;
+                                break;
+                            case 2:
+                                channel.Precisions[i] = 3 * channel.Precisions[i] / 8;
+                                break;
+                            case 3:
+                                channel.Precisions[i] /= 4;
+                                break;
+                        }
+                    }
+                }
+            }
+            else
+            {
+                for (int i = 0; i < block.QuantizationUnitCount; i++)
+                {
+                    channel.Precisions[i] = channel.ScaleFactors[i] - block.Gradient[i];
+                }
+            }
+
+            for (int i = 0; i < block.QuantizationUnitCount; i++)
+            {
+                if (channel.Precisions[i] < 1)
+                {
+                    channel.Precisions[i] = 1;
+                }
+            }
+
+            for (int i = 0; i < block.GradientBoundary; i++)
+            {
+                channel.Precisions[i]++;
+            }
+
+            for (int i = 0; i < block.QuantizationUnitCount; i++)
+            {
+                channel.PrecisionsFine[i] = 0;
+                if (channel.Precisions[i] > 15)
+                {
+                    channel.PrecisionsFine[i] = channel.Precisions[i] - 15;
+                    channel.Precisions[i] = 15;
+                }
+            }
+        }
+
+        public static byte[][] GenerateGradientCurves()
+        {
+            byte[] main =
+            {
+                01, 01, 01, 01, 02, 02, 02, 02, 03, 03, 03, 04, 04, 05, 05, 06, 07, 08, 09, 10, 11, 12, 13, 15,
+                16, 18, 19, 20, 21, 22, 23, 24, 25, 26, 26, 27, 27, 28, 28, 28, 29, 29, 29, 29, 30, 30, 30, 30
+            };
+            var curves = new byte[main.Length][];
+
+            for (int length = 1; length <= main.Length; length++)
+            {
+                curves[length - 1] = new byte[length];
+                for (int i = 0; i < length; i++)
+                {
+                    curves[length - 1][i] = main[i * main.Length / length];
+                }
+            }
+            return curves;
+        }
+    }
+}