Stop using glTransformFeedbackVaryings and use explicit layout on the shader (#3012)

* Stop using glTransformFeedbackVarying and use explicit layout on the shader

* This is no longer needed

* Shader cache version bump

* Fix gl_PerVertex output for tessellation control shaders

5 files changed, 106 insertions, 29 deletions

diff --git a/Ryujinx.Graphics.Gpu/Shader/CachedGpuAccessor.cs b/Ryujinx.Graphics.Gpu/Shader/CachedGpuAccessor.cs
index 21d08823..d65349a5 100644
--- a/Ryujinx.Graphics.Gpu/Shader/CachedGpuAccessor.cs
+++ b/Ryujinx.Graphics.Gpu/Shader/CachedGpuAccessor.cs
@@ -13,6 +13,7 @@ namespace Ryujinx.Graphics.Gpu.Shader
         private readonly ReadOnlyMemory<byte> _cb1Data;
         private readonly GuestGpuAccessorHeader _header;
         private readonly Dictionary<int, GuestTextureDescriptor> _textureDescriptors;
+        private readonly TransformFeedbackDescriptor[] _tfd;
 
         /// <summary>
         /// Creates a new instance of the cached GPU state accessor for shader translation.
@@ -27,7 +28,8 @@ namespace Ryujinx.Graphics.Gpu.Shader
             ReadOnlyMemory<byte> data,
             ReadOnlyMemory<byte> cb1Data,
             GuestGpuAccessorHeader header,
-            IReadOnlyDictionary<int, GuestTextureDescriptor> guestTextureDescriptors) : base(context)
+            IReadOnlyDictionary<int, GuestTextureDescriptor> guestTextureDescriptors,
+            TransformFeedbackDescriptor[] tfd) : base(context)
         {
             _data = data;
             _cb1Data = cb1Data;
@@ -38,6 +40,8 @@ namespace Ryujinx.Graphics.Gpu.Shader
             {
                 _textureDescriptors.Add(guestTextureDescriptor.Key, guestTextureDescriptor.Value);
             }
+
+            _tfd = tfd;
         }
 
         /// <summary>
@@ -178,6 +182,35 @@ namespace Ryujinx.Graphics.Gpu.Shader
         }
 
         /// <summary>
+        /// Queries transform feedback enable state.
+        /// </summary>
+        /// <returns>True if the shader uses transform feedback, false otherwise</returns>
+        public bool QueryTransformFeedbackEnabled()
+        {
+            return _tfd != null;
+        }
+
+        /// <summary>
+        /// Queries the varying locations that should be written to the transform feedback buffer.
+        /// </summary>
+        /// <param name="bufferIndex">Index of the transform feedback buffer</param>
+        /// <returns>Varying locations for the specified buffer</returns>
+        public ReadOnlySpan<byte> QueryTransformFeedbackVaryingLocations(int bufferIndex)
+        {
+            return _tfd[bufferIndex].VaryingLocations;
+        }
+
+        /// <summary>
+        /// Queries the stride (in bytes) of the per vertex data written into the transform feedback buffer.
+        /// </summary>
+        /// <param name="bufferIndex">Index of the transform feedback buffer</param>
+        /// <returns>Stride for the specified buffer</returns>
+        public int QueryTransformFeedbackStride(int bufferIndex)
+        {
+            return _tfd[bufferIndex].Stride;
+        }
+
+        /// <summary>
         /// Queries if host state forces early depth testing.
         /// </summary>
         /// <returns>True if early depth testing is forced</returns>
diff --git a/Ryujinx.Graphics.Gpu/Shader/GpuAccessor.cs b/Ryujinx.Graphics.Gpu/Shader/GpuAccessor.cs
index 64604a99..a5c7575f 100644
--- a/Ryujinx.Graphics.Gpu/Shader/GpuAccessor.cs
+++ b/Ryujinx.Graphics.Gpu/Shader/GpuAccessor.cs
@@ -223,6 +223,35 @@ namespace Ryujinx.Graphics.Gpu.Shader
         }
 
         /// <summary>
+        /// Queries transform feedback enable state.
+        /// </summary>
+        /// <returns>True if the shader uses transform feedback, false otherwise</returns>
+        public bool QueryTransformFeedbackEnabled()
+        {
+            return _state.TransformFeedbackDescriptors != null;
+        }
+
+        /// <summary>
+        /// Queries the varying locations that should be written to the transform feedback buffer.
+        /// </summary>
+        /// <param name="bufferIndex">Index of the transform feedback buffer</param>
+        /// <returns>Varying locations for the specified buffer</returns>
+        public ReadOnlySpan<byte> QueryTransformFeedbackVaryingLocations(int bufferIndex)
+        {
+            return _state.TransformFeedbackDescriptors[bufferIndex].VaryingLocations;
+        }
+
+        /// <summary>
+        /// Queries the stride (in bytes) of the per vertex data written into the transform feedback buffer.
+        /// </summary>
+        /// <param name="bufferIndex">Index of the transform feedback buffer</param>
+        /// <returns>Stride for the specified buffer</returns>
+        public int QueryTransformFeedbackStride(int bufferIndex)
+        {
+            return _state.TransformFeedbackDescriptors[bufferIndex].Stride;
+        }
+
+        /// <summary>
         /// Queries if host state forces early depth testing.
         /// </summary>
         /// <returns>True if early depth testing is forced</returns>
diff --git a/Ryujinx.Graphics.Gpu/Shader/GpuAccessorState.cs b/Ryujinx.Graphics.Gpu/Shader/GpuAccessorState.cs
index ebbf3b69..6818072b 100644
--- a/Ryujinx.Graphics.Gpu/Shader/GpuAccessorState.cs
+++ b/Ryujinx.Graphics.Gpu/Shader/GpuAccessorState.cs
@@ -39,6 +39,11 @@ namespace Ryujinx.Graphics.Gpu.Shader
         public TessMode TessellationMode { get; }
 
         /// <summary>
+        /// Transform feedback information, if the shader uses transform feedback. Otherwise, should be null.
+        /// </summary>
+        public TransformFeedbackDescriptor[] TransformFeedbackDescriptors { get; set; }
+
+        /// <summary>
         /// Creates a new instance of the GPU accessor state.
         /// </summary>
         /// <param name="texturePoolGpuVa">GPU virtual address of the texture pool</param>
@@ -61,6 +66,7 @@ namespace Ryujinx.Graphics.Gpu.Shader
             EarlyZForce = earlyZForce;
             Topology = topology;
             TessellationMode = tessellationMode;
+            TransformFeedbackDescriptors = null;
         }
     }
 }
\ No newline at end of file
diff --git a/Ryujinx.Graphics.Gpu/Shader/ShaderCache.cs b/Ryujinx.Graphics.Gpu/Shader/ShaderCache.cs
index 4c6224e3..110115e7 100644
--- a/Ryujinx.Graphics.Gpu/Shader/ShaderCache.cs
+++ b/Ryujinx.Graphics.Gpu/Shader/ShaderCache.cs
@@ -40,7 +40,7 @@ namespace Ryujinx.Graphics.Gpu.Shader
         /// <summary>
         /// Version of the codegen (to be changed when codegen or guest format change).
         /// </summary>
-        private const ulong ShaderCodeGenVersion = 2972;
+        private const ulong ShaderCodeGenVersion = 3012;
 
         // Progress reporting helpers
         private volatile int _shaderCount;
@@ -227,7 +227,8 @@ namespace Ryujinx.Graphics.Gpu.Shader
                                             binaryCode,
                                             binaryCode.Slice(binaryCode.Length - entry.Header.Cb1DataSize),
                                             entry.Header.GpuAccessorHeader,
-                                            entry.TextureDescriptors);
+                                            entry.TextureDescriptors,
+                                            null);
 
                                         var options = new TranslationOptions(TargetLanguage.Glsl, TargetApi.OpenGL, DefaultFlags | TranslationFlags.Compute);
                                         program = Translator.CreateContext(0, gpuAccessor, options).Translate(out shaderProgramInfo);
@@ -251,7 +252,7 @@ namespace Ryujinx.Graphics.Gpu.Shader
 
                                         // Compile shader and create program as the shader program binary got invalidated.
                                         shader.HostShader = _context.Renderer.CompileShader(ShaderStage.Compute, program.Code);
-                                        hostProgram = _context.Renderer.CreateProgram(new IShader[] { shader.HostShader }, null);
+                                        hostProgram = _context.Renderer.CreateProgram(new IShader[] { shader.HostShader });
 
                                         task.OnCompiled(hostProgram, (bool isNewProgramValid, ShaderCompileTask task) =>
                                         {
@@ -293,13 +294,6 @@ namespace Ryujinx.Graphics.Gpu.Shader
 
                             TransformFeedbackDescriptor[] tfd = CacheHelper.ReadTransformFeedbackInformation(ref guestProgramReadOnlySpan, fileHeader);
 
-                            TranslationFlags flags = DefaultFlags;
-
-                            if (tfd != null)
-                            {
-                                flags |= TranslationFlags.Feedback;
-                            }
-
                             TranslationCounts counts = new TranslationCounts();
 
                             HostShaderCacheEntry[] hostShaderEntries = null;
@@ -343,15 +337,16 @@ namespace Ryujinx.Graphics.Gpu.Shader
                                                 binaryCode,
                                                 binaryCode.Slice(binaryCode.Length - entry.Header.Cb1DataSize),
                                                 entry.Header.GpuAccessorHeader,
-                                                entry.TextureDescriptors);
+                                                entry.TextureDescriptors,
+                                                tfd);
 
-                                            var options = new TranslationOptions(TargetLanguage.Glsl, TargetApi.OpenGL, flags);
+                                            var options = new TranslationOptions(TargetLanguage.Glsl, TargetApi.OpenGL, DefaultFlags);
 
                                             shaderContexts[i + 1] = Translator.CreateContext(0, gpuAccessor, options, counts);
 
                                             if (entry.Header.SizeA != 0)
                                             {
-                                                var options2 = new TranslationOptions(TargetLanguage.Glsl, TargetApi.OpenGL, flags | TranslationFlags.VertexA);
+                                                var options2 = new TranslationOptions(TargetLanguage.Glsl, TargetApi.OpenGL, DefaultFlags | TranslationFlags.VertexA);
 
                                                 shaderContexts[0] = Translator.CreateContext((ulong)entry.Header.Size, gpuAccessor, options2, counts);
                                             }
@@ -431,7 +426,7 @@ namespace Ryujinx.Graphics.Gpu.Shader
                                             hostShaders.Add(hostShader);
                                         }
 
-                                        hostProgram = _context.Renderer.CreateProgram(hostShaders.ToArray(), tfd);
+                                        hostProgram = _context.Renderer.CreateProgram(hostShaders.ToArray());
 
                                         task.OnCompiled(hostProgram, (bool isNewProgramValid, ShaderCompileTask task) =>
                                         {
@@ -622,7 +617,7 @@ namespace Ryujinx.Graphics.Gpu.Shader
 
                 shader.HostShader = _context.Renderer.CompileShader(ShaderStage.Compute, shader.Program.Code);
 
-                IProgram hostProgram = _context.Renderer.CreateProgram(new IShader[] { shader.HostShader }, null);
+                IProgram hostProgram = _context.Renderer.CreateProgram(new IShader[] { shader.HostShader });
 
                 cpShader = new ShaderBundle(hostProgram, shader);
 
@@ -684,25 +679,20 @@ namespace Ryujinx.Graphics.Gpu.Shader
 
             TransformFeedbackDescriptor[] tfd = GetTransformFeedbackDescriptors(ref state);
 
-            TranslationFlags flags = DefaultFlags;
-
-            if (tfd != null)
-            {
-                flags |= TranslationFlags.Feedback;
-            }
+            gas.TransformFeedbackDescriptors = tfd;
 
             TranslationCounts counts = new TranslationCounts();
 
             if (addresses.VertexA != 0)
             {
-                shaderContexts[0] = DecodeGraphicsShader(channel, gas, counts, flags | TranslationFlags.VertexA, ShaderStage.Vertex, addresses.VertexA);
+                shaderContexts[0] = DecodeGraphicsShader(channel, gas, counts, DefaultFlags | TranslationFlags.VertexA, ShaderStage.Vertex, addresses.VertexA);
             }
 
-            shaderContexts[1] = DecodeGraphicsShader(channel, gas, counts, flags, ShaderStage.Vertex, addresses.Vertex);
-            shaderContexts[2] = DecodeGraphicsShader(channel, gas, counts, flags, ShaderStage.TessellationControl, addresses.TessControl);
-            shaderContexts[3] = DecodeGraphicsShader(channel, gas, counts, flags, ShaderStage.TessellationEvaluation, addresses.TessEvaluation);
-            shaderContexts[4] = DecodeGraphicsShader(channel, gas, counts, flags, ShaderStage.Geometry, addresses.Geometry);
-            shaderContexts[5] = DecodeGraphicsShader(channel, gas, counts, flags, ShaderStage.Fragment, addresses.Fragment);
+            shaderContexts[1] = DecodeGraphicsShader(channel, gas, counts, DefaultFlags, ShaderStage.Vertex, addresses.Vertex);
+            shaderContexts[2] = DecodeGraphicsShader(channel, gas, counts, DefaultFlags, ShaderStage.TessellationControl, addresses.TessControl);
+            shaderContexts[3] = DecodeGraphicsShader(channel, gas, counts, DefaultFlags, ShaderStage.TessellationEvaluation, addresses.TessEvaluation);
+            shaderContexts[4] = DecodeGraphicsShader(channel, gas, counts, DefaultFlags, ShaderStage.Geometry, addresses.Geometry);
+            shaderContexts[5] = DecodeGraphicsShader(channel, gas, counts, DefaultFlags, ShaderStage.Fragment, addresses.Fragment);
 
             bool isShaderCacheEnabled = _cacheManager != null;
             bool isShaderCacheReadOnly = false;
@@ -765,7 +755,7 @@ namespace Ryujinx.Graphics.Gpu.Shader
                     hostShaders.Add(hostShader);
                 }
 
-                IProgram hostProgram = _context.Renderer.CreateProgram(hostShaders.ToArray(), tfd);
+                IProgram hostProgram = _context.Renderer.CreateProgram(hostShaders.ToArray());
 
                 gpShaders = new ShaderBundle(hostProgram, shaders);
 
diff --git a/Ryujinx.Graphics.Gpu/Shader/TransformFeedbackDescriptor.cs b/Ryujinx.Graphics.Gpu/Shader/TransformFeedbackDescriptor.cs
new file mode 100644
index 00000000..eaa889cc
--- /dev/null
+++ b/Ryujinx.Graphics.Gpu/Shader/TransformFeedbackDescriptor.cs
@@ -0,0 +1,19 @@
+using System;
+
+namespace Ryujinx.Graphics.Gpu.Shader
+{
+    struct TransformFeedbackDescriptor
+    {
+        public int BufferIndex { get; }
+        public int Stride      { get; }
+
+        public byte[] VaryingLocations { get; }
+
+        public TransformFeedbackDescriptor(int bufferIndex, int stride, byte[] varyingLocations)
+        {
+            BufferIndex      = bufferIndex;
+            Stride           = stride;
+            VaryingLocations = varyingLocations ?? throw new ArgumentNullException(nameof(varyingLocations));
+        }
+    }
+}