Upgrade Version

Core/RenderManager.cs

@@ -5,7 +5,6 @@ using System.IO;
 using System.Threading;
 using System.Buffers;
 using System.Diagnostics;
-using System.Linq;
 using ADOFAIRenderer.API;
 using ADOFAIRenderer.Core.Data;
 using ADOFAIRenderer.Data;
@@ -81,8 +80,28 @@ internal class RenderManager : MonoBehaviour
     public static bool IsActive => Instance && Instance.stage >= RenderStage.OnScene;
     public static bool IsCapturingActive => Instance && Instance.stage >= RenderStage.Render;
 
+    /// <summary>
+    /// Maximum number of frames in ImageQueue. The main thread waits (throttles) while the queue holds more frames.
+    /// </summary>
     public const int MaxQueuedFrames = 64;
 
+    /// <summary>
+    /// Upper bound of the readback buffer bytes of the frames in ImageQueue (4 GiB).
+    /// The frame limit becomes min(MaxQueuedFrames, MaxQueuedBytes / bytes per frame) (see ComputeQueueFrameLimit),
+    /// so it only lowers the frame count at resolutions where MaxQueuedFrames frames exceed this size.
+    /// </summary>
+    public const long MaxQueuedBytes = 4L * 1024 * 1024 * 1024;
+
+    /// <summary>
+    /// Wait time of the throttle loop (OnPostFrame) for the render thread to take a frame from ImageQueue.
+    /// When it elapses without a dequeue, AsyncGPUReadback.WaitAllRequests() is called once so the readbacks
+    /// still in flight complete (the render thread may be waiting for one of them to fill a gap in ImageQueue).
+    /// </summary>
+    private const int ThrottleWaitMilliseconds = 10;
+
+    /// <summary>Frame limit of ImageQueue applied by the last throttle check (MaxQueuedFrames or lower).</summary>
+    public int QueueFrameLimit { get; private set; } = MaxQueuedFrames;
+        
     // Statistics
     public long framesSent;
     private readonly Stopwatch _renderStopwatch = new();
@@ -213,6 +232,8 @@ internal class RenderManager : MonoBehaviour
     // Thread and Queue State
     internal SortedList<long, CapturedFrame> ImageQueue = new();
     internal AutoResetEvent FrameAvailableEvent = new(false);
+    // Set by the render thread each time it takes a frame from ImageQueue; the throttle loop waits on it.
+    internal AutoResetEvent FrameDequeuedEvent = new(false);
     public Thread? RenderThread;
     public long passCount;
     public volatile bool endRequested;
@@ -439,13 +460,30 @@ internal class RenderManager : MonoBehaviour
         _holdFloorsSourceCount = floors.Count;
     }
 
+    /// <summary>
+    /// Frame limit of ImageQueue for the given capture texture: MaxQueuedBytes divided by the readback bytes of
+    /// one frame (YUV 4:2:0 when the GPU conversion is active, RGBA otherwise), within 4 to MaxQueuedFrames.
+    /// </summary>
+    private int ComputeQueueFrameLimit(RenderTexture texture)
+    {
+        var frameBytes = _frameReader?.GetFrameBufferBytes(texture.width, texture.height)
+                         ?? (long)texture.width * texture.height * 4;
+        if (frameBytes <= 0) return MaxQueuedFrames;
+
+        return (int)Math.Min(MaxQueuedFrames, Math.Max(4, MaxQueuedBytes / frameBytes));
+    }
+
     // ReSharper disable once Unity.IncorrectMethodSignature
     public void OnPostFrame(RenderTexture? texture)
     {
         if (Instance.stage < RenderStage.Render || !texture) return;
 
         // [Backpressure Throttling]
+        // The main thread waits while ImageQueue holds more than QueueFrameLimit frames. Only the render thread
+        // removes frames, and it signals FrameDequeuedEvent for each one. The wait has a timeout so that the loop
+        // re-checks the render thread state and pumps pending readback completions (see ThrottleWaitMilliseconds).
         isThrottling = false;
+        var frameLimit = QueueFrameLimit = ComputeQueueFrameLimit(texture!);
 
         while (Instance.stage >= RenderStage.Render)
         {
@@ -461,7 +499,7 @@ internal class RenderManager : MonoBehaviour
                 count = ImageQueue.Count;
             }
 
-            if (count <= MaxQueuedFrames) break;
+            if (count <= frameLimit) break;
 
             if (!isThrottling)
             {
@@ -469,7 +507,10 @@ internal class RenderManager : MonoBehaviour
                 throttleCount++;
             }
                 
-            AsyncGPUReadback.WaitAllRequests();
+            if (!FrameDequeuedEvent.WaitOne(ThrottleWaitMilliseconds))
+            {
+                AsyncGPUReadback.WaitAllRequests();
+            }
         }
         isThrottling = false;
 
@@ -649,6 +690,7 @@ internal class RenderManager : MonoBehaviour
         endRequested = false;
         endSuccessful = false;
         FrameAvailableEvent.Reset();
+        FrameDequeuedEvent.Reset();
 
         var renderFPS = Configuration.RenderFPS;
         var videoFPS = Configuration.VideoFPS;
@@ -712,7 +754,7 @@ internal class RenderManager : MonoBehaviour
             throw;
         }
 
-        var encoder = videoFFmpeg!;
+        var encoder = videoFFmpeg;
         RenderThread = new Thread(() => RunRenderThread(encoder))
         {
             IsBackground = true,
@@ -775,6 +817,7 @@ internal class RenderManager : MonoBehaviour
 
             if (TryDequeueNextFrame(out var frame))
             {
+                FrameDequeuedEvent.Set();
                 SendVideoFrame(videoFFmpeg, frame);
                 WriteAudioForFrame(videoFFmpeg);
                 continue;

RenderMod.cs

@@ -9,7 +9,7 @@ using MelonLoader.Utils;
 using UnityEngine;
 using Object = UnityEngine.Object;
 
-[assembly: MelonInfo(typeof(RenderMod), "ADOFAI Renderer", "0.2.8-INDEV", "ADOFAI Editor Forum")]
+[assembly: MelonInfo(typeof(RenderMod), "ADOFAI Renderer", "0.4.0-BETA", "ADOFAI Editor Forum")]
 [assembly: MelonGame("7th Beat Games", "A Dance of Fire and Ice")]
 
 namespace ADOFAIRenderer;

UI/DebugMonitorUI.cs

@@ -164,7 +164,7 @@ internal class DebugMonitorUI : MonoBehaviour
             }
         }
             
-        sb.AppendLine($"• Queue: <b>{queueCount}</b> / {RenderManager.MaxQueuedFrames} frames");
+        sb.AppendLine($"• Queue: <b>{queueCount}</b> / {(RenderManager.Instance ? RenderManager.Instance.QueueFrameLimit : RenderManager.MaxQueuedFrames)} frames");
         sb.AppendLine($"• Rendered Frames: <b>{(RenderManager.Instance ? RenderManager.Instance.frameCount : 0)}</b>");
         sb.AppendLine($"• Frames Sent: <b>{(RenderManager.Instance ? Interlocked.Read(ref RenderManager.Instance.framesSent) : 0)}</b>");
             

Util/FFmpeg/FFmpegNativeEncoder.cs

@@ -201,6 +201,12 @@ namespace ADOFAIRenderer.Util.FFmpeg
         /// </summary>
         private AVPixelFormat _dstPixFmt = AVPixelFormat.AV_PIX_FMT_YUV420P;
 
+        /// <summary>
+        /// Color range of the encoder input and output (codec context color_range of the selected encoder).
+        /// Full range (JPEG) for every encoder except libvvenc, limited range (MPEG) for libvvenc.
+        /// </summary>
+        private AVColorRange _colorRange = AVColorRange.AVCOL_RANGE_JPEG;
+
         /// <summary>Pixel format of the finally selected and running encoder.</summary>
         public AVPixelFormat SelectedPixelFormat => _dstPixFmt;
 
@@ -399,7 +405,19 @@ namespace ADOFAIRenderer.Util.FFmpeg
                         // ── Basic video parameters configuration ──
                         _pCodecContext->width = _settings.Width;
                         _pCodecContext->height = _settings.Height;
-                        _pCodecContext->color_range = AVColorRange.AVCOL_RANGE_JPEG;
+
+                        // ── Output color tags ──
+                        // Matrix: BT.709, the RGB→YUV matrix of both conversion paths
+                        //   (GPU: RGB2YUV_BT709_Full in ColorConversion.compute, CPU: ConfigureSwsColorspace).
+                        //   Players use this tag to convert the YUV frames back to RGB.
+                        // Range: full (0-255) for every encoder except libvvenc, limited (16-235) for libvvenc.
+                        //   The FFmpeg libvvenc wrapper passes the matrix/primaries/transfer tags to VVenC but not the range,
+                        //   so a VVC stream is read as limited range; its input is converted to limited range to match.
+                        // Reference: https://github.com/FFmpeg/FFmpeg/blob/release/8.0/libavcodec/libvvenc.c (vvenc_set_color_format)
+                        _pCodecContext->color_range = encoder == VideoEncoder.LibVvenc
+                            ? AVColorRange.AVCOL_RANGE_MPEG
+                            : AVColorRange.AVCOL_RANGE_JPEG;
+                        _pCodecContext->colorspace = AVColorSpace.AVCOL_SPC_BT709;
                         // thread_count = 0: FFmpeg automatically allocates threads according to the system CPU core count.
                         // For libvvenc, the FFmpeg wrapper passes thread_count as the VVenC internal thread count,
                         // so setting 0 (auto) is required for parallel encoding utilizing all cores.
@@ -756,6 +774,7 @@ namespace ADOFAIRenderer.Util.FFmpeg
                             var accelStatus = isHardware ? "Hardware Acceleration Enabled" : "Software CPU Usage";
                             Melon<RenderMod>.Logger.Msg($"Video encoder successfully initialized: {encoder.Name} ({accelStatus})");
                             _dstPixFmt = selectedPixFmt;
+                            _colorRange = _pCodecContext->color_range;
                             openedSuccessfully = true;
                             break;
                         }
@@ -855,6 +874,8 @@ namespace ADOFAIRenderer.Util.FFmpeg
                     if (_pSwsContext == null)
                         throw new Exception("Failed to initialize software scaler.");
 
+                    ConfigureSwsColorspace();
+
                     _isInitialized = true;
                     _loggedConversionMode = false;
                 }
@@ -1240,7 +1261,51 @@ namespace ADOFAIRenderer.Util.FFmpeg
         }
 
         /// <summary>
-        /// Sets the format, size and color range of the destination frame (_pDstFrame) and allocates a new pixel buffer for it.
+        /// Sets the RGB→YUV conversion of the CPU conversion path (_pSwsContext) to the BT.709 matrix
+        /// and the color range of the encoder (_colorRange), so that it produces the same colors as the GPU path
+        /// (RGB2YUV_BT709_Full in ColorConversion.compute) and as the tags of the output stream.
+        /// A new libswscale context uses the BT.601 matrix (SWS_CS_DEFAULT = SWS_CS_ITU601) and the limited range.
+        ///
+        /// For RGB input, "table" holds the coefficients of the output YUV space and dstRange its range (1 = full, 0 = limited).
+        /// The source (RGB) values, brightness, contrast and saturation keep the values of the context.
+        ///
+        /// Reference: https://ffmpeg.org/doxygen/trunk/group__libsws.html (sws_setColorspaceDetails, sws_getCoefficients)
+        /// Reference: https://github.com/FFmpeg/FFmpeg/blob/release/8.0/libswscale/swscale.h (SWS_CS_ITU709, SWS_CS_DEFAULT)
+        /// </summary>
+        private void ConfigureSwsColorspace()
+        {
+            int* currentInvTable;
+            int* currentTable;
+            int srcRange, dstRange, brightness, contrast, saturation;
+
+            var ret = ffmpeg.sws_getColorspaceDetails(_pSwsContext, &currentInvTable, &srcRange, &currentTable, &dstRange,
+                &brightness, &contrast, &saturation);
+            if (ret < 0)
+            {
+                Melon<RenderMod>.Logger.Warning($"[Encoder] Cannot read the colorspace details of the software scaler: {GetFFmpegErrorString(ret)} (Code: {ret}). The CPU conversion path keeps the libswscale defaults.");
+                return;
+            }
+
+            var coefficients = ffmpeg.sws_getCoefficients(ffmpeg.SWS_CS_ITU709);
+            var invTable = new int_array4();
+            var table = new int_array4();
+            for (uint i = 0; i < 4; i++)
+            {
+                invTable[i] = currentInvTable[i];
+                table[i] = coefficients[i];
+            }
+
+            var fullRange = _colorRange == AVColorRange.AVCOL_RANGE_JPEG;
+            ret = ffmpeg.sws_setColorspaceDetails(_pSwsContext, invTable, srcRange, table, fullRange ? 1 : 0,
+                brightness, contrast, saturation);
+            if (ret < 0)
+            {
+                Melon<RenderMod>.Logger.Warning($"[Encoder] Cannot set the colorspace details of the software scaler: {GetFFmpegErrorString(ret)} (Code: {ret}). The CPU conversion path keeps the libswscale defaults.");
+            }
+        }
+
+        /// <summary>
+        /// Sets the format, size, color range and matrix of the destination frame (_pDstFrame) and allocates a new pixel buffer for it.
         /// av_frame_get_buffer allocates memory matching format, width and height and sets the data[]/linesize[] pointers.
         /// Second argument 0 means default alignment.
         /// Reference: https://ffmpeg.org/doxygen/trunk/group__lavu__frame.html (av_frame_get_buffer)
@@ -1250,7 +1315,8 @@ namespace ADOFAIRenderer.Util.FFmpeg
             _pDstFrame->format = (int)_dstPixFmt;
             _pDstFrame->width = _settings.Width;
             _pDstFrame->height = _settings.Height;
-            _pDstFrame->color_range = AVColorRange.AVCOL_RANGE_JPEG;
+            _pDstFrame->color_range = _colorRange;
+            _pDstFrame->colorspace = AVColorSpace.AVCOL_SPC_BT709;
 
             var ret = ffmpeg.av_frame_get_buffer(_pDstFrame, 0);
             if (ret < 0)

Util/FrameReader.cs

@@ -73,6 +73,16 @@ namespace ADOFAIRenderer.Util
             }
         }
 
+        /// <summary>
+        /// Bytes of the readback buffer of one frame: Width x Height x 3 / 2 when the GPU conversion to NV12 / YUV420P
+        /// is used, Width x Height x 4 (RGBA) otherwise. The same size as ReadbackRequestState.Setup uses.
+        /// </summary>
+        public long GetFrameBufferBytes(int width, int height)
+        {
+            var pixels = (long)width * height;
+            return _useGPUConversion ? pixels * 3 / 2 : pixels * 4;
+        }
+
         public void RequestFrameCapture(Texture texture, long currentFrame)
         {
             if (!RenderManager.IsCapturingActive) return;