small backup

Ghost.Graphics/D3D12/D3D12CommandBuffer.cs

@@ -383,7 +383,7 @@ internal unsafe class D3D12CommandBuffer : ICommandBuffer
         for (var i = 0; i < rtDescs.Length; i++)
         {
             var rtDesc = rtDescs[i];
-            if (!rtDesc.Texture.IsValid)
+            if (rtDesc.Texture.IsInvalid)
             {
                 RecordError(nameof(BeginRenderPass), ErrorStatus.InvalidArgument);
                 continue;
@@ -396,7 +396,7 @@ internal unsafe class D3D12CommandBuffer : ICommandBuffer
                 continue;
             }
 
-            var record = recordResult.Value;
+            ref var record = ref recordResult.Value;
             var cpuHandle = _descriptorAllocator.GetCpuHandle(record.viewGroup.rtv);
             var format = record.desc.TextureDescription.Format.ToDXGIFormat();
             var clearColor = rtDesc.ClearColor;
@@ -431,7 +431,7 @@ internal unsafe class D3D12CommandBuffer : ICommandBuffer
                 return;
             }
 
-            var record = recordResult.Value;
+            ref var record = ref recordResult.Value;
             var cpuHandle = _descriptorAllocator.GetCpuHandle(record.viewGroup.dsv);
             var format = record.desc.TextureDescription.Format.ToDXGIFormat();
 
@@ -544,7 +544,7 @@ internal unsafe class D3D12CommandBuffer : ICommandBuffer
             return;
         }
 
-        var record = recordResult.Value;
+        ref var record = ref recordResult.Value;
         var vbView = new D3D12_VERTEX_BUFFER_VIEW
         {
             BufferLocation = record.ResourcePtr.Get()->GetGPUVirtualAddress() + offset,

Ghost.RenderGraph.Concept/RenderGraph.cs

@@ -166,35 +166,42 @@ public sealed class RenderGraph
                 offset = ComputeTextureHash(pData, offset, pass.colorAccess[j].id);
             }
 
-            *(int*)(pData + offset) = pass.resourceReads.Count;
+            for (var j = 0; j < (int)RenderGraphResourceType.Count; j++)
-            offset += sizeof(int);
-            for (var j = 0; j < pass.resourceReads.Count; j++)
             {
-                *(int*)(pData + offset) = pass.resourceReads[j].Value;
+                var readList = pass.resourceReads[j];
-                offset += sizeof(int);
+                var writeList = pass.resourceWrites[j];
-            }
+                var createList = pass.resourceCreates[j];
 
-            *(int*)(pData + offset) = pass.resourceWrites.Count;
+                *(int*)(pData + offset) = readList.Count;
-            offset += sizeof(int);
-            for (var j = 0; j < pass.resourceWrites.Count; j++)
-            {
-                *(int*)(pData + offset) = pass.resourceWrites[j].Value;
                 offset += sizeof(int);
-            }
+                for (var k = 0; k < readList.Count; k++)
+                {
+                    *(int*)(pData + offset) = readList[k].Value;
+                    offset += sizeof(int);
+                }
 
-            *(int*)(pData + offset) = pass.resourceCreates.Count;
+                *(int*)(pData + offset) = writeList.Count;
-            offset += sizeof(int);
-            for (var j = 0; j < pass.resourceCreates.Count; j++)
-            {
-                *(int*)(pData + offset) = pass.resourceCreates[j].Value;
                 offset += sizeof(int);
+                for (var k = 0; k < writeList.Count; k++)
+                {
+                    *(int*)(pData + offset) = writeList[k].Value;
+                    offset += sizeof(int);
+                }
+
+                *(int*)(pData + offset) = createList.Count;
+                offset += sizeof(int);
+                for (var k = 0; k < createList.Count; k++)
+                {
+                    *(int*)(pData + offset) = createList[k].Value;
+                    offset += sizeof(int);
+                }
             }
         }
 
         //// Hash resource descriptors
-        //for (var i = 0; i < _resources.TextureResourceCount; i++)
+        //for (var j = 0; j < _resources.TextureResourceCount; j++)
         //{
-        //    var resource = _resources.GetTextureResourceByIndex(i);
+        //    var resource = _resources.GetTextureResourceByIndex(j);
 
         //    *(int*)(pData + offset) = resource.descriptor.width;
         //    offset += sizeof(int);
@@ -260,15 +267,19 @@ public sealed class RenderGraph
         {
             var pass = _passes[i];
 
-            // Check if this pass writes to any imported textures
+            // Check if this pass writes to any imported resources
-            for (var j = 0; j < pass.resourceWrites.Count; j++)
+            for (var j = 0; j < (int)RenderGraphResourceType.Count; j++)
             {
-                var writeHandle = pass.resourceWrites[j];
+                var writeList = pass.resourceWrites[j];
-                var resource = _resources.GetResource(writeHandle);
+                for (var k = 0; k < writeList.Count; k++)
-                if (resource.isImported)
                 {
-                    pass.hasSideEffects = true;
+                    var writeHandle = writeList[k];
-                    break;
+                    var resource = _resources.GetResource(writeHandle);
+                    if (resource.isImported)
+                    {
+                        pass.hasSideEffects = true;
+                        break;
+                    }
                 }
             }
         }
@@ -403,13 +414,17 @@ public sealed class RenderGraph
     private void UnculDependencies(RenderGraphPassBase pass)
     {
         // Un-cull producers of read resources
-        for (var i = 0; i < pass.resourceReads.Count; i++)
+        for (var i = 0; i < (int)RenderGraphResourceType.Count; i++)
         {
-            UnculProducer(pass.resourceReads[i]);
+            var readList = pass.resourceReads[i];
+            for (var j = 0; j < readList.Count; j++)
+            {
+                UnculProducer(readList[j]);
+            }
         }
 
         // Un-cull producers of color attachments
-        for (var i = 0; i <= pass.maxColorIndex; i++)
+        for (var i = 0; i < pass.maxColorIndex; i++)
         {
             if (pass.colorAccess[i].id.IsValid)
             {
@@ -533,16 +548,20 @@ public sealed class RenderGraph
     private void InsertTransitionBarriers(RenderGraphPassBase pass, int passIdx)
     {
         // Process reads (transition to shader resource)
-        for (var i = 0; i < pass.resourceReads.Count; i++)
+        for (var i = 0; i < (int)RenderGraphResourceType.Count; i++)
         {
-            var handle = pass.resourceReads[i];
+            var readList = pass.resourceReads[i];
-            InsertTransitionIfNeeded(handle, ResourceState.ShaderResource, passIdx);
+            for (var j = 0; j < readList.Count; j++)
+            {
+                var handle = readList[j];
+                InsertTransitionIfNeeded(handle, ResourceState.ShaderResource, passIdx);
+            }
         }
 
         switch (pass.type)
         {
             case RenderPassType.Raster:
-                for (var i = 0; i <= pass.maxColorIndex; i++)
+                for (var i = 0; i < pass.maxColorIndex; i++)
                 {
                     var access = pass.colorAccess[i];
                     InsertTransitionIfNeeded(access.id.AsResource(), ResourceState.RenderTarget, passIdx);
@@ -561,10 +580,14 @@ public sealed class RenderGraph
 
                 break;
             case RenderPassType.Compute:
-                for (var i = 0; i < pass.resourceWrites.Count; i++)
+                for (var i = 0; i < (int)RenderGraphResourceType.Count; i++)
                 {
-                    var id = pass.resourceWrites[i];
+                    var writeList = pass.resourceWrites[i];
-                    InsertTransitionIfNeeded(id, ResourceState.UnorderedAccess, passIdx);
+                    for (var j = 0; j < writeList.Count; j++)
+                    {
+                        var id = writeList[j];
+                        InsertTransitionIfNeeded(id, ResourceState.UnorderedAccess, passIdx);
+                    }
                 }
 
                 break;

Ghost.RenderGraph.Concept/RenderGraph.cs.bak

@@ -0,0 +1,663 @@
+using Ghost.Core;
+using Misaki.HighPerformance.LowLevel.Buffer;
+using Misaki.HighPerformance.LowLevel.Collections;
+using System.IO.Hashing;
+using TerraFX.Interop.Windows;
+
+namespace Ghost.RenderGraph.Concept;
+
+/// <summary>
+/// Main render graph class that manages resource allocation and pass execution.
+/// 
+/// Design principles for minimal GC:
+/// - Object pooling for all passes and resources
+/// - Reuse collections across frames (Clear() instead of new)
+/// - Avoid LINQ and foreach over interfaces
+/// - Pre-allocate capacity based on expected usage
+/// </summary>
+public sealed class RenderGraph
+{
+    private readonly RenderGraphResourceRegistry _resources = new();
+    private readonly RenderGraphObjectPool _objectPool = new();
+    private readonly List<RenderGraphPassBase> _passes = new(64);
+    private readonly List<RenderGraphPassBase> _compiledPasses = new(64);
+    private readonly RenderGraphBuilder _builder = new();
+    private readonly MockCommandBuffer _commandBuffer = new();
+    private readonly RenderContext _renderContext;
+    private readonly ResourceAliasingManager _aliasingManager = new();
+    private readonly Dictionary<int, ResourceState> _resourceStates = new(128);
+    private readonly List<ResourceBarrier> _barriers = new(128);
+    private readonly RenderGraphCompilationCache _compilationCache = new();
+
+    private bool _compiled;
+
+    public RenderGraphBlackboard Blackboard { get; } = new();
+
+    public RenderGraph()
+    {
+        _renderContext = new RenderContext(_commandBuffer);
+    }
+
+    /// <summary>
+    /// Resets the render graph for a new frame.
+    /// Reuses existing allocations to minimize GC.
+    /// </summary>
+    public void Reset()
+    {
+        // Clear blackboard data
+        Blackboard.Clear();
+
+        // Reset resources but keep allocations
+        _resources.BeginFrame();
+
+        // Reset aliasing manager
+        _aliasingManager.BeginFrame();
+
+        // Clear resource states and barriers
+        _resourceStates.Clear();
+        _barriers.Clear();
+
+        // Return passes to the pool and reset count
+        for (var i = 0; i < _passes.Count; i++)
+        {
+            var pass = _passes[i];
+            pass.Reset(_objectPool);
+        }
+
+        _passes.Clear();
+
+        // Clear compiled passes list
+        _compiledPasses.Clear();
+        _compiled = false;
+    }
+
+    /// <summary>
+    /// Imports an external texture into the render graph.
+    /// </summary>
+    public Identifier<RGTexture> ImportTexture(TextureDescriptor descriptor)
+    {
+        return _resources.ImportTexture(descriptor);
+    }
+
+    public IRasterRenderGraphBuilder AddRasterRenderPass<TPassData>(string name, out TPassData passData)
+        where TPassData : class, new()
+    {
+        var renderPass = _objectPool.Rent<RasterRenderGraphPass<TPassData>>();
+        renderPass.Init(_passes.Count, _objectPool.Rent<TPassData>(), name, RenderPassType.Raster);
+        passData = renderPass.passData;
+
+        _passes.Add(renderPass);
+
+        _builder.Init(this, renderPass, _resources);
+        return _builder;
+    }
+
+    public IComputeRenderGraphBuilder AddComputeRenderPass<TPassData>(string name, out TPassData passData)
+        where TPassData : class, new()
+    {
+        var renderPass = _objectPool.Rent<ComputeRenderGraphPass<TPassData>>();
+        renderPass.Init(_passes.Count, _objectPool.Rent<TPassData>(), name, RenderPassType.Compute);
+        passData = renderPass.passData;
+
+        _passes.Add(renderPass);
+
+        _builder.Init(this, renderPass, _resources);
+        return _builder;
+    }
+
+    private unsafe int ComputeTextureHash(byte* pData, int offset, Identifier<RGTexture> texture)
+    {
+        if (texture.IsInvalid)
+        {
+            return offset;
+        }
+
+        var resource = _resources.GetResource(texture.AsResource());
+
+        // In real implementation, we typically need to handle imported resources differently.
+
+        *(pData + offset) = resource.isImported ? (byte)1 : (byte)0;
+        offset += sizeof(byte);
+
+        *(TextureFormat*)(pData + offset) = resource.descriptor.format;
+        offset += sizeof(TextureFormat);
+        
+        *(int*)(pData + offset) = resource.descriptor.width;
+        offset += sizeof(int);
+
+        *(int*)(pData + offset) = resource.descriptor.height;
+        offset += sizeof(int);
+
+        return offset;
+    }
+
+    private unsafe ulong ComputeGraphHash()
+    {
+        using var scope = AllocationManager.CreateStackScope();
+        var bufferPool = new UnsafeList<byte>(2048, scope.AllocationHandle);
+        var pData = (byte*)bufferPool.GetUnsafePtr();
+        var offset = 0;
+
+        // Hash pass count
+        *(int*)(pData + offset) = _passes.Count;
+        offset += sizeof(int);
+
+        // Hash each pass structure (excluding names)
+        for (var i = 0; i < _passes.Count; i++)
+        {
+            var pass = _passes[i];
+
+            *(RenderPassType*)(pData + offset) = pass.type;
+            offset += sizeof(RenderPassType);
+
+            *(bool*)(pData + offset) = pass.allowCulling;
+            offset += sizeof(bool);
+
+            *(bool*)(pData + offset) = pass.asyncCompute;
+            offset += sizeof(bool);
+
+            // Hash depth attachment
+            offset = ComputeTextureHash(pData, offset, pass.depthAccess.id);
+
+            *(int*)(pData + offset) = pass.maxColorIndex;
+            offset += sizeof(int);
+            for (var j = 0; j <= pass.maxColorIndex; j++)
+            {
+                offset = ComputeTextureHash(pData, offset, pass.colorAccess[j].id);
+            }
+
+            *(int*)(pData + offset) = pass.resourceReads.Count;
+            offset += sizeof(int);
+            for (var j = 0; j < pass.resourceReads.Count; j++)
+            {
+                *(int*)(pData + offset) = pass.resourceReads[j].Value;
+                offset += sizeof(int);
+            }
+
+            *(int*)(pData + offset) = pass.resourceWrites.Count;
+            offset += sizeof(int);
+            for (var j = 0; j < pass.resourceWrites.Count; j++)
+            {
+                *(int*)(pData + offset) = pass.resourceWrites[j].Value;
+                offset += sizeof(int);
+            }
+
+            *(int*)(pData + offset) = pass.resourceCreates.Count;
+            offset += sizeof(int);
+            for (var j = 0; j < pass.resourceCreates.Count; j++)
+            {
+                *(int*)(pData + offset) = pass.resourceCreates[j].Value;
+                offset += sizeof(int);
+            }
+        }
+
+        //// Hash resource descriptors
+        //for (var i = 0; i < _resources.TextureResourceCount; i++)
+        //{
+        //    var resource = _resources.GetTextureResourceByIndex(i);
+
+        //    *(int*)(pData + offset) = resource.descriptor.width;
+        //    offset += sizeof(int);
+
+        //    *(int*)(pData + offset) = resource.descriptor.height;
+        //    offset += sizeof(int);
+
+        //    *(TextureFormat*)(pData + offset) = resource.descriptor.format;
+        //    offset += sizeof(TextureFormat);
+
+        //    *(bool*)(pData + offset) = resource.isImported;
+        //    offset += sizeof(bool);
+        //}
+
+        var span = new Span<byte>(pData, offset);
+        return XxHash64.HashToUInt64(span);
+    }
+
+    /// <summary>
+    /// Compiles the render graph by culling unused passes and determining resource lifetimes.
+    /// </summary>
+    public void Compile()
+    {
+        if (_compiled)
+        {
+            return;
+        }
+
+#if DEBUG
+        var sw = System.Diagnostics.Stopwatch.StartNew();
+#endif
+
+        // Step 0: Check cache
+        var graphHash = ComputeGraphHash(); // 17020363347016000737
+
+#if DEBUG
+        var hashTime = sw.Elapsed.TotalMicroseconds;
+#endif
+
+        if (_compilationCache.TryGetCached(graphHash, out var cached))
+        {
+            // CACHE HIT - restore from cache
+#if DEBUG
+            Console.WriteLine($"\n[CACHE HIT] Hash: {graphHash:X16} (computed in {hashTime:F2}μs)");
+#endif
+            RestoreFromCache(cached);
+#if DEBUG
+            sw.Stop();
+            Console.WriteLine($"[CACHE HIT] Total restore time: {sw.Elapsed.TotalMicroseconds:F2}μs");
+#endif
+            _compiled = true;
+            return;
+        }
+
+#if DEBUG
+        Console.WriteLine($"\n[CACHE MISS] Hash: {graphHash:X16} (computed in {hashTime:F2}μs)");
+#endif
+
+        _compiledPasses.Clear();
+
+        // Step 1: Mark passes with side effects (writes to imported resources)
+        for (var i = 0; i < _passes.Count; i++)
+        {
+            var pass = _passes[i];
+
+            // Check if this pass writes to any imported textures
+            for (var j = 0; j < pass.resourceWrites.Count; j++)
+            {
+                var writeHandle = pass.resourceWrites[j];
+                var resource = _resources.GetResource(writeHandle);
+                if (resource.isImported)
+                {
+                    pass.hasSideEffects = true;
+                    break;
+                }
+            }
+        }
+
+        // Step 2: Cull passes based on dependency analysis
+        // Mark all passes as culled initially
+        for (var i = 0; i < _passes.Count; i++)
+        {
+            _passes[i].culled = _passes[i].allowCulling && !_passes[i].hasSideEffects;
+        }
+
+        // Step 3: Traverse backwards from passes with side effects
+        for (var i = _passes.Count - 1; i >= 0; i--)
+        {
+            var pass = _passes[i];
+            if (!pass.culled)
+            {
+                UnculDependencies(pass);
+            }
+        }
+
+        // Step 4: Build final pass list (only non-culled passes)
+        for (var i = 0; i < _passes.Count; i++)
+        {
+            var pass = _passes[i];
+            if (!pass.culled)
+            {
+                _compiledPasses.Add(pass);
+            }
+        }
+
+        // Step 5: Perform resource aliasing to minimize memory usage
+        _aliasingManager.AssignPhysicalResources(_resources, _passes.Count);
+
+        // Step 6: Generate barriers for state transitions and aliasing
+        GenerateBarriers();
+
+        // Step 7: Store in cache for future frames
+        StoreInCache(graphHash);
+
+        _compiled = true;
+    }
+
+    /// <summary>
+    /// Restores the render graph state from cached compilation results.
+    /// </summary>
+    private void RestoreFromCache(CachedCompilation cached)
+    {
+        // Restore compiled pass list
+        _compiledPasses.Clear();
+        for (var i = 0; i < cached.compiledPassIndices.Count; i++)
+        {
+            var passIndex = cached.compiledPassIndices[i];
+            _compiledPasses.Add(_passes[passIndex]);
+        }
+
+        // Restore culling flags
+        for (var i = 0; i < _passes.Count && i < cached.passCulledFlags.Count; i++)
+        {
+            _passes[i].culled = cached.passCulledFlags[i];
+        }
+
+        // Restore aliasing mappings (need to update ResourceAliasingManager)
+        _aliasingManager.RestoreFromCache(cached.logicalToPhysical, cached.physicalResources);
+
+        // Restore barriers (deep copy to avoid shared references)
+        _barriers.Clear();
+        for (var i = 0; i < cached.barriers.Count; i++)
+        {
+            _barriers.Add(cached.barriers[i]);
+        }
+
+        // Restore resource states
+        _resourceStates.Clear();
+        foreach (var kvp in cached.resourceStates)
+        {
+            _resourceStates[kvp.Key] = kvp.Value;
+        }
+    }
+
+    /// <summary>
+    /// Stores current compilation results in the cache.
+    /// </summary>
+    private void StoreInCache(ulong graphHash)
+    {
+        var cacheData = new CachedCompilation();
+
+        // Store compiled pass indices
+        for (var i = 0; i < _compiledPasses.Count; i++)
+        {
+            cacheData.compiledPassIndices.Add(_compiledPasses[i].index);
+        }
+
+        // Store culling flags for all passes
+        for (var i = 0; i < _passes.Count; i++)
+        {
+            cacheData.passCulledFlags.Add(_passes[i].culled);
+        }
+
+        // Store aliasing mappings
+        _aliasingManager.StoreToCache(cacheData.logicalToPhysical, cacheData.physicalResources);
+
+        // Store barriers
+        for (var i = 0; i < _barriers.Count; i++)
+        {
+            cacheData.barriers.Add(_barriers[i]);
+        }
+
+        // Store resource states
+        foreach (var kvp in _resourceStates)
+        {
+            cacheData.resourceStates[kvp.Key] = kvp.Value;
+        }
+
+        _compilationCache.Store(graphHash, cacheData);
+    }
+
+    private void UnculProducer(Identifier<RGResource> resource)
+    {
+        var res = _resources.GetResource(resource);
+        if (res.producerPass >= 0)
+        {
+            var producer = _passes[res.producerPass];
+            if (producer.culled)
+            {
+                producer.culled = false;
+                UnculDependencies(producer);
+            }
+        }
+    }
+
+    private void UnculDependencies(RenderGraphPassBase pass)
+    {
+        // Un-cull producers of read resources
+        for (var i = 0; i < pass.resourceReads.Count; i++)
+        {
+            UnculProducer(pass.resourceReads[i]);
+        }
+
+        // Un-cull producers of color attachments
+        for (var i = 0; i <= pass.maxColorIndex; i++)
+        {
+            if (pass.colorAccess[i].id.IsValid)
+            {
+                UnculProducer(pass.colorAccess[i].id.AsResource());
+            }
+        }
+
+        // Un-cull producer of depth attachment
+        if (pass.depthAccess.id.IsValid)
+        {
+            UnculProducer(pass.depthAccess.id.AsResource());
+        }
+
+        // Un-cull producers of UAV resources (if not already in reads/writes)
+        for (var i = 0; i < pass.randomAccess.Count; i++)
+        {
+            UnculProducer(pass.randomAccess[i]);
+        }
+    }
+
+    /// <summary>
+    /// Generates resource barriers for state transitions and aliasing.
+    /// </summary>
+    private void GenerateBarriers()
+    {
+        _barriers.Clear();
+        _resourceStates.Clear();
+
+#if DEBUG
+        Console.WriteLine("\n=== Barrier Generation ===");
+#endif
+
+        // Process each compiled pass in order
+        for (var passIdx = 0; passIdx < _compiledPasses.Count; passIdx++)
+        {
+            var pass = _compiledPasses[passIdx];
+
+            // Insert aliasing barriers for resources that reuse physical memory
+            InsertAliasingBarriers(pass, passIdx);
+
+            // Insert transition barriers for state changes
+            InsertTransitionBarriers(pass, passIdx);
+        }
+
+#if DEBUG
+        Console.WriteLine($"Total Barriers: {_barriers.Count}");
+        Console.WriteLine("==========================\n");
+#endif
+    }
+
+    /// <summary>
+    /// Inserts aliasing barriers when a physical resource is reused.
+    /// </summary>
+    private void InsertAliasingBarriers(RenderGraphPassBase pass, int passIdx)
+    {
+        // Check all resources written by this pass
+        for (var i = 0; i < pass.resourceWrites.Count; i++)
+        {
+            var id = pass.resourceWrites[i];
+            var resource = _resources.GetResource(id);
+
+            // Skip imported resources
+            if (resource.isImported)
+                continue;
+
+            // Check if this is the first use of this logical resource
+            if (resource.firstUsePass == pass.index)
+            {
+                // Rent the physical resource
+                var physicalIndex = _aliasingManager.GetPhysicalResourceIndex(id.Value);
+                if (physicalIndex >= 0)
+                {
+                    var physical = _aliasingManager.GetPhysicalResource(physicalIndex);
+
+                    // If this physical resource has multiple aliased resources,
+                    // we need an aliasing barrier when switching between them
+                    if (physical != null && physical.aliasedLogicalResources.Count > 1)
+                    {
+                        // Find the resource that used this physical memory most recently before this pass
+                        Identifier<RGResource> resourceBefore = default;
+                        var mostRecentLastUse = -1;
+
+                        foreach (var otherLogicalIndex in physical.aliasedLogicalResources)
+                        {
+                            if (otherLogicalIndex != id.Value)
+                            {
+                                var otherResource = _resources.GetTextureResourceByIndex(otherLogicalIndex);
+                                // Check if this resource finished before our resource starts
+                                if (otherResource.lastUsePass < pass.index &&
+                                    otherResource.lastUsePass > mostRecentLastUse)
+                                {
+                                    mostRecentLastUse = otherResource.lastUsePass;
+                                    resourceBefore = otherLogicalIndex;
+                                }
+                            }
+                        }
+
+                        // If we found a previous resource, insert aliasing barrier
+                        if (mostRecentLastUse >= 0)
+                        {
+                            var barrier = ResourceBarrier.CreateAliasingBarrier(
+                                resourceBefore,
+                                id,
+                                passIdx
+                            );
+                            _barriers.Add(barrier);
+
+#if DEBUG
+                            Console.WriteLine($"  {barrier}");
+#endif
+                        }
+                    }
+                }
+            }
+        }
+    }
+
+    /// <summary>
+    /// Inserts transition barriers when a resource changes state.
+    /// </summary>
+    private void InsertTransitionBarriers(RenderGraphPassBase pass, int passIdx)
+    {
+        // Process reads (transition to shader resource)
+        for (var i = 0; i < pass.resourceReads.Count; i++)
+        {
+            var handle = pass.resourceReads[i];
+            InsertTransitionIfNeeded(handle, ResourceState.ShaderResource, passIdx);
+        }
+
+        switch (pass.type)
+        {
+            case RenderPassType.Raster:
+                for (var i = 0; i <= pass.maxColorIndex; i++)
+                {
+                    var access = pass.colorAccess[i];
+                    InsertTransitionIfNeeded(access.id.AsResource(), ResourceState.RenderTarget, passIdx);
+                }
+
+                if (pass.depthAccess.id.IsValid)
+                {
+                    var depthAccess = pass.depthAccess;
+                    InsertTransitionIfNeeded(depthAccess.id.AsResource(), ResourceState.DepthWrite, passIdx);
+                }
+
+                for (var i = 0; i < pass.randomAccess.Count; i++)
+                {
+                    InsertTransitionIfNeeded(pass.randomAccess[i], ResourceState.UnorderedAccess, passIdx);
+                }
+
+                break;
+            case RenderPassType.Compute:
+                for (var i = 0; i < pass.resourceWrites.Count; i++)
+                {
+                    var id = pass.resourceWrites[i];
+                    InsertTransitionIfNeeded(id, ResourceState.UnorderedAccess, passIdx);
+                }
+
+                break;
+        }
+    }
+
+    /// <summary>
+    /// Inserts a transition barrier if the resource state changes.
+    /// </summary>
+    private void InsertTransitionIfNeeded(Identifier<RGResource> resource, ResourceState newState, int passIdx)
+    {
+        if (!_resourceStates.TryGetValue(resource.Value, out var currentState))
+        {
+            // First time seeing this resource, assume undefined
+            currentState = ResourceState.Common;
+        }
+
+        if (currentState != newState)
+        {
+            var barrier = ResourceBarrier.CreateTransitionBarrier(
+                resource,
+                currentState,
+                newState,
+                passIdx
+            );
+            _barriers.Add(barrier);
+            _resourceStates[resource.Value] = newState;
+
+#if DEBUG
+            Console.WriteLine($"  {barrier}");
+#endif
+        }
+    }
+
+    /// <summary>
+    /// Executes all compiled passes.
+    /// </summary>
+    public void Execute()
+    {
+        if (!_compiled)
+        {
+            Compile();
+        }
+
+        // Execute each non-culled pass
+        var barrierIndex = 0;
+        for (var i = 0; i < _compiledPasses.Count; i++)
+        {
+            var pass = _compiledPasses[i];
+
+            // Execute all barriers for this pass
+#if DEBUG
+            bool hasBarriers = false;
+#endif
+            while (barrierIndex < _barriers.Count && _barriers[barrierIndex].PassIndex == i)
+            {
+#if DEBUG
+                if (!hasBarriers)
+                {
+                    Console.WriteLine($"\n=== Barriers before Pass {i}: {pass.name} ===");
+                    hasBarriers = true;
+                }
+
+                var barrier = _barriers[barrierIndex];
+                if (barrier.Type == BarrierType.Transition)
+                {
+                    _commandBuffer.ResourceBarrier(
+                        barrier.Resource,
+                        barrier.StateBefore,
+                        barrier.StateAfter
+                    );
+                }
+                else if (barrier.Type == BarrierType.Aliasing)
+                {
+                    _commandBuffer.AliasBarrier(
+                        barrier.ResourceBefore,
+                        barrier.ResourceAfter
+                    );
+                }
+#endif
+                // In a real implementation, you would execute the barrier here:
+                // ExecuteBarrier(_barriers[barrierIndex]);
+
+                barrierIndex++;
+            }
+#if DEBUG
+            if (hasBarriers)
+            {
+                Console.WriteLine("=====================================\n");
+            }
+#endif
+
+            pass.Execute(_renderContext);
+        }
+    }
+}

Ghost.RenderGraph.Concept/RenderGraphAliasing.cs.bak

@@ -0,0 +1,329 @@
+using Ghost.Core.Utilities;
+
+namespace Ghost.RenderGraph.Concept;
+
+/// <summary>
+/// Represents a physical GPU resource that can be aliased by multiple logical resources.
+/// </summary>
+internal sealed class PhysicalResource
+{
+    public int index;
+    public int width;
+    public int height;
+    public TextureFormat format;
+    public int sizeInBytes;
+    
+    // Lifetime tracking
+    public int firstUsePass = int.MaxValue;
+    public int lastUsePass = -1;
+    
+    // Aliasing tracking
+    public readonly List<int> aliasedLogicalResources = new(4);
+
+    public void Reset()
+    {
+        index = -1;
+        width = 0;
+        height = 0;
+        format = TextureFormat.RGBA8;
+        sizeInBytes = 0;
+        firstUsePass = int.MaxValue;
+        lastUsePass = -1;
+        aliasedLogicalResources.Clear();
+    }
+
+    public bool CanAlias(TextureDescriptor descriptor)
+    {
+        // For aliasing, resources must be identical in size and format
+        // In a real implementation, you could be more flexible (e.g., same size but different format)
+        return width == descriptor.width &&
+               height == descriptor.height &&
+               format == descriptor.format;
+    }
+
+    public void UpdateLifetime(int passIndex)
+    {
+        firstUsePass = Math.Min(firstUsePass, passIndex);
+        lastUsePass = Math.Max(lastUsePass, passIndex);
+    }
+
+    public bool IsAliveAt(int passIndex)
+    {
+        return passIndex >= firstUsePass && passIndex <= lastUsePass;
+    }
+
+    public int CalculateSize()
+    {
+        int bytesPerPixel = format switch
+        {
+            TextureFormat.RGBA8 => 4,
+            TextureFormat.RGBA16F => 8,
+            TextureFormat.RGBA32F => 16,
+            TextureFormat.Depth32F => 4,
+            TextureFormat.Depth24Stencil8 => 4,
+            _ => 4
+        };
+        return width * height * bytesPerPixel;
+    }
+}
+
+/// <summary>
+/// Manages physical resource allocation and aliasing.
+/// Uses interval scheduling algorithm to minimize memory usage.
+/// </summary>
+internal sealed class ResourceAliasingManager
+{
+    private readonly List<PhysicalResource> _physicalResources = new(32);
+    private readonly RenderGraphObjectPool _pool = new();
+    private int _physicalResourceCount;
+    
+    // Mapping from logical resource index to physical resource index
+    private readonly Dictionary<int, int> _logicalToPhysical = new(64);
+
+    public void BeginFrame()
+    {
+        _physicalResourceCount = 0;
+        _logicalToPhysical.Clear();
+        
+        // Reset physical resources but keep them in the pool
+        for (int i = 0; i < _physicalResources.Count; i++)
+        {
+            _physicalResources[i].Reset();
+        }
+    }
+
+    /// <summary>
+    /// Assigns physical resources to logical resources using greedy interval scheduling.
+    /// This minimizes total GPU memory usage.
+    /// </summary>
+    public void AssignPhysicalResources(RenderGraphResourceRegistry registry, int passCount)
+    {
+#if DEBUG
+        Console.WriteLine("\n=== Resource Aliasing Analysis ===");
+        int totalLogicalSize = 0;
+#endif
+
+        // Build list of all logical resources with their lifetimes
+        var logicalResources = ListPool<(int index, RenderGraphResource resource)>.Rent();
+        
+        for (int i = 0; i < registry.TextureResourceCount; i++)
+        {
+            var resource = registry.GetTextureResourceByIndex(i);
+            if (!resource.isImported) // Don't alias imported resources
+            {
+                logicalResources.Add((i, resource));
+#if DEBUG
+                int size = CalculateSize(resource.descriptor);
+                totalLogicalSize += size;
+                Console.WriteLine($"Logical Resource {i}: {resource.descriptor.name}");
+                Console.WriteLine($"  Lifetime: Pass {resource.firstUsePass} -> {resource.lastUsePass}");
+                Console.WriteLine($"  Size: {size / 1024.0:F2} KB");
+#endif
+            }
+        }
+
+        // Sort by first use pass (earlier resources first)
+        logicalResources.Sort((a, b) => a.resource.firstUsePass.CompareTo(b.resource.firstUsePass));
+
+        // Greedy interval scheduling: assign each logical resource to a physical resource
+        foreach (var (logicalIndex, logicalResource) in logicalResources)
+        {
+            PhysicalResource? assignedPhysical = null;
+
+            // Try to find an existing physical resource that:
+            // 1. Has compatible format/size
+            // 2. Is not alive during this logical resource's lifetime
+            for (int i = 0; i < _physicalResourceCount; i++)
+            {
+                var physical = _physicalResources[i];
+                
+                if (physical.CanAlias(logicalResource.descriptor) &&
+                    !HasLifetimeOverlap(physical, logicalResource))
+                {
+                    assignedPhysical = physical;
+                    break;
+                }
+            }
+
+            // No compatible physical resource found, allocate a new one
+            if (assignedPhysical == null)
+            {
+                assignedPhysical = GetOrCreatePhysicalResource();
+                assignedPhysical.index = _physicalResourceCount - 1;
+                assignedPhysical.width = logicalResource.descriptor.width;
+                assignedPhysical.height = logicalResource.descriptor.height;
+                assignedPhysical.format = logicalResource.descriptor.format;
+                assignedPhysical.sizeInBytes = assignedPhysical.CalculateSize();
+                
+#if DEBUG
+                Console.WriteLine($"\nAllocated NEW Physical Resource {assignedPhysical.index}:");
+                Console.WriteLine($"  Size: {assignedPhysical.width}x{assignedPhysical.height}");
+                Console.WriteLine($"  Format: {assignedPhysical.format}");
+                Console.WriteLine($"  Memory: {assignedPhysical.sizeInBytes / 1024.0:F2} KB");
+#endif
+            }
+#if DEBUG
+            else
+            {
+                Console.WriteLine($"\nALIASING: {logicalResource.descriptor.name} -> Physical Resource {assignedPhysical.index}");
+            }
+#endif
+
+            // Update physical resource lifetime
+            assignedPhysical.UpdateLifetime(logicalResource.firstUsePass);
+            assignedPhysical.UpdateLifetime(logicalResource.lastUsePass);
+            assignedPhysical.aliasedLogicalResources.Add(logicalIndex);
+
+            // Record the mapping
+            _logicalToPhysical[logicalIndex] = assignedPhysical.index;
+        }
+
+#if DEBUG
+        int totalPhysicalSize = 0;
+        for (int i = 0; i < _physicalResourceCount; i++)
+        {
+            totalPhysicalSize += _physicalResources[i].sizeInBytes;
+        }
+        
+        Console.WriteLine($"\n=== Aliasing Summary ===");
+        Console.WriteLine($"Logical Resources: {logicalResources.Count}");
+        Console.WriteLine($"Physical Resources: {_physicalResourceCount}");
+        Console.WriteLine($"Total Logical Memory: {totalLogicalSize / 1024.0:F2} KB");
+        Console.WriteLine($"Total Physical Memory: {totalPhysicalSize / 1024.0:F2} KB");
+        Console.WriteLine($"Memory Saved: {(totalLogicalSize - totalPhysicalSize) / 1024.0:F2} KB ({(1.0 - (double)totalPhysicalSize / totalLogicalSize) * 100.0:F1}%)");
+        Console.WriteLine("================================\n");
+#endif
+
+        ListPool<(int index, RenderGraphResource resource)>.Return(logicalResources);
+    }
+
+    public int GetPhysicalResourceIndex(int logicalIndex)
+    {
+        return _logicalToPhysical.TryGetValue(logicalIndex, out var physicalIndex) ? physicalIndex : -1;
+    }
+
+    public PhysicalResource? GetPhysicalResource(int physicalIndex)
+    {
+        return physicalIndex >= 0 && physicalIndex < _physicalResourceCount 
+            ? _physicalResources[physicalIndex] 
+            : null;
+    }
+
+    private bool HasLifetimeOverlap(PhysicalResource physical, RenderGraphResource logical)
+    {
+        // Check if the lifetimes overlap
+        // No overlap if: logical.First > physical.Last OR logical.Last < physical.First
+        return !(logical.firstUsePass > physical.lastUsePass || 
+                 logical.lastUsePass < physical.firstUsePass);
+    }
+
+    private PhysicalResource GetOrCreatePhysicalResource()
+    {
+        PhysicalResource resource;
+        if (_physicalResourceCount < _physicalResources.Count)
+        {
+            resource = _physicalResources[_physicalResourceCount];
+            resource.Reset();
+        }
+        else
+        {
+            resource = _pool.Rent<PhysicalResource>();
+            resource.Reset();
+            _physicalResources.Add(resource);
+        }
+
+        _physicalResourceCount++;
+        return resource;
+    }
+
+    private static int CalculateSize(TextureDescriptor descriptor)
+    {
+        int bytesPerPixel = descriptor.format switch
+        {
+            TextureFormat.RGBA8 => 4,
+            TextureFormat.RGBA16F => 8,
+            TextureFormat.RGBA32F => 16,
+            TextureFormat.Depth32F => 4,
+            TextureFormat.Depth24Stencil8 => 4,
+            _ => 4
+        };
+        return descriptor.width * descriptor.height * bytesPerPixel;
+    }
+
+    public void Clear()
+    {
+        for (int i = 0; i < _physicalResources.Count; i++)
+        {
+            _pool.Return(_physicalResources[i]);
+        }
+        _physicalResources.Clear();
+        _physicalResourceCount = 0;
+        _logicalToPhysical.Clear();
+    }
+
+    /// <summary>
+    /// Restores aliasing state from cache.
+    /// </summary>
+    public void RestoreFromCache(Dictionary<int, int> logicalToPhysical, List<PhysicalResourceData> physicalData)
+    {
+        _logicalToPhysical.Clear();
+        foreach (var kvp in logicalToPhysical)
+        {
+            _logicalToPhysical[kvp.Key] = kvp.Value;
+        }
+
+        // Restore physical resources
+        _physicalResourceCount = physicalData.Count;
+        for (int i = 0; i < physicalData.Count; i++)
+        {
+            PhysicalResource physical;
+            if (i < _physicalResources.Count)
+            {
+                physical = _physicalResources[i];
+                physical.Reset();
+            }
+            else
+            {
+                physical = _pool.Rent<PhysicalResource>();
+                physical.Reset();
+                _physicalResources.Add(physical);
+            }
+
+            var data = physicalData[i];
+            physical.index = data.index;
+            physical.width = data.width;
+            physical.height = data.height;
+            physical.format = data.format;
+            physical.firstUsePass = data.firstUsePass;
+            physical.lastUsePass = data.lastUsePass;
+            physical.sizeInBytes = physical.CalculateSize();
+        }
+    }
+
+    /// <summary>
+    /// Stores current aliasing state to cache.
+    /// </summary>
+    public void StoreToCache(Dictionary<int, int> outLogicalToPhysical, List<PhysicalResourceData> outPhysicalData)
+    {
+        outLogicalToPhysical.Clear();
+        foreach (var kvp in _logicalToPhysical)
+        {
+            outLogicalToPhysical[kvp.Key] = kvp.Value;
+        }
+
+        outPhysicalData.Clear();
+        for (int i = 0; i < _physicalResourceCount; i++)
+        {
+            var physical = _physicalResources[i];
+            outPhysicalData.Add(new PhysicalResourceData
+            {
+                index = physical.index,
+                width = physical.width,
+                height = physical.height,
+                format = physical.format,
+                firstUsePass = physical.firstUsePass,
+                lastUsePass = physical.lastUsePass
+            });
+        }
+    }
+}

Ghost.RenderGraph.Concept/RenderGraphBuilder.cs

@@ -110,17 +110,17 @@ internal class RenderGraphBuilder : IRasterRenderGraphBuilder, IComputeRenderGra
         ObjectDisposedException.ThrowIf(_disposed, this);
     }
 
-    private Identifier<RGResource> UseResource(Identifier<RGResource> resource, AccessFlags accessFlags)
+    private Identifier<RGResource> UseResource(Identifier<RGResource> resource, AccessFlags accessFlags, RenderGraphResourceType type)
     {
         if (accessFlags.HasFlag(AccessFlags.Read))
         {
-            _pass.resourceReads.Add(resource);
+            _pass.resourceReads[(int)type].Add(resource);
             _resources.AddConsumer(resource, _pass.index);
         }
 
         if (accessFlags.HasFlag(AccessFlags.Write))
         {
-            _pass.resourceWrites.Add(resource);
+            _pass.resourceWrites[(int)type].Add(resource);
             _resources.SetProducer(resource, _pass.index);
         }
 
@@ -142,7 +142,7 @@ internal class RenderGraphBuilder : IRasterRenderGraphBuilder, IComputeRenderGra
         ThrowIfDisposed();
 
         var handle = _resources.CreateTexture(descriptor);
-        _pass.resourceCreates.Add(handle.AsResource());
+        _pass.resourceCreates[(int)RenderGraphResourceType.Texture].Add(handle.AsResource());
         _resources.SetProducer(handle.AsResource(), _pass.index);
         return handle;
     }
@@ -150,8 +150,7 @@ internal class RenderGraphBuilder : IRasterRenderGraphBuilder, IComputeRenderGra
     public Identifier<RGTexture> UseTexture(Identifier<RGTexture> texture, AccessFlags flags)
     {
         ThrowIfDisposed();
-
+        return UseResource(texture.AsResource(), flags, RenderGraphResourceType.Texture).AsTexture();
-        return UseResource(texture.AsResource(), flags).AsTexture();
     }
 
     public Identifier<RGTexture> UseRandomAccessTexture(Identifier<RGTexture> texture)
@@ -159,7 +158,7 @@ internal class RenderGraphBuilder : IRasterRenderGraphBuilder, IComputeRenderGra
         ThrowIfDisposed();
 
         var resource = texture.AsResource();
-        UseResource(resource, AccessFlags.ReadWrite);
+        UseResource(resource, AccessFlags.ReadWrite, RenderGraphResourceType.Texture);
         _pass.randomAccess.Add(resource);
         return texture;
     }
@@ -169,7 +168,7 @@ internal class RenderGraphBuilder : IRasterRenderGraphBuilder, IComputeRenderGra
         ThrowIfDisposed();
 
         var resource = buffer.AsResource();
-        UseResource(resource, AccessFlags.ReadWrite);
+        UseResource(resource, AccessFlags.ReadWrite, RenderGraphResourceType.Buffer);
         _pass.randomAccess.Add(resource);
         return buffer;
     }

Ghost.RenderGraph.Concept/RenderGraphBuilder.cs.bak

@@ -0,0 +1,240 @@
+using Ghost.Core;
+using System.Diagnostics;
+
+namespace Ghost.RenderGraph.Concept;
+
+[Flags]
+public enum AccessFlags
+{
+    None = 0,
+    Read = 1 << 0,
+    Write = 1 << 1,
+    ReadWrite = Read | Write,
+}
+
+public interface IRenderGraphBuilder : IDisposable
+{
+    /// <summary>
+    /// Enables or disables pass culling for the current context.
+    /// </summary>
+    /// <param name="value">A value indicating whether pass culling is allowed.</param>
+    void AllowPassCulling(bool value);
+
+    /// <summary>
+    /// Creates a new texture resource based on the specified descriptor.
+    /// </summary>
+    /// <param name="descriptor">A structure that defines the properties and configuration of the texture to create.</param>
+    /// <returns>An identifier for the newly created texture resource.</returns>
+    Identifier<RGTexture> CreateTexture(in TextureDescriptor descriptor);
+
+    /// <summary>
+    /// Registers the specified texture for use in the current render graph pass with the given access mode.
+    /// </summary>
+    /// <param name="texture">The identifier of the texture to be used in the render graph pass.</param>
+    /// <param name="accessMode">The access mode specifying how the texture will be read or written during the pass.</param>
+    /// <returns>An identifier for the texture.</returns>
+    Identifier<RGTexture> UseTexture(Identifier<RGTexture> texture, AccessFlags accessMode);
+}
+
+public interface IRasterRenderGraphBuilder : IRenderGraphBuilder
+{
+    /// <summary>
+    /// Binds a texture for random access operations within the current rendering pass.
+    /// </summary>
+    /// <param name="texture">The identifier of the texture to be used for random access.</param>
+    /// <returns>An identifier for the texture.</returns>
+    Identifier<RGTexture> UseRandomAccessTexture(Identifier<RGTexture> texture);
+    /// <summary>
+    /// Specifies that the given buffer will be used for random access operations with the specified access mode within the current context.
+    /// </summary>
+    /// <param name="buffer">An identifier for the buffer to be used for random access. Must reference a valid buffer resource.</param>
+    /// <returns>An identifier for the buffer.</returns>
+    Identifier<RGBuffer> UseRandomAccessBuffer(Identifier<RGBuffer> buffer);
+
+    /// <summary>
+    /// Sets the color attachment at the specified index to the given texture.
+    /// </summary>
+    /// <param name="texture">The identifier of the texture to use as the color attachment.</param>
+    /// <param name="index">The zero-based index of the color attachment to set.</param>
+    void SetColorAttachment(Identifier<RGTexture> texture, int index);
+
+    /// <summary>
+    /// Sets the depth attachment for the current render pass using the specified texture.
+    /// </summary>
+    /// <param name="texture">The identifier of the texture to use as the depth attachment. Cannot be null.</param>
+    void SetDepthAttachment(Identifier<RGTexture> texture);
+
+    /// <summary>
+    /// Sets the function used to render a pass with the specified pass data and render context.
+    /// </summary>
+    /// <typeparam name="TPassData">The type of data associated with the render pass.</typeparam>
+    /// <param name="renderFunc">The delegate that defines the rendering logic for the pass.</param>
+    void SetRenderFunc<TPassData>(Action<TPassData, RasterRenderContext> renderFunc)
+        where TPassData : class, new();
+}
+
+public interface IComputeRenderGraphBuilder : IRenderGraphBuilder
+{
+    /// <summary>
+    /// Enables or disables asynchronous compute operations.
+    /// </summary>
+    /// <param name="value">true to enable asynchronous compute; otherwise, false.</param>
+    void EnableAsyncCompute(bool value);
+
+    /// <summary>
+    /// Sets the render function to be invoked during the compute rendering process.
+    /// </summary>
+    /// <typeparam name="TPassData">The type of the data object passed to the render function.</typeparam>
+    /// <param name="renderFunc">The delegate that defines the rendering logic to execute.</param>
+    void SetRenderFunc<TPassData>(Action<TPassData, ComputeRenderContext> renderFunc)
+        where TPassData : class, new();
+}
+
+internal class RenderGraphBuilder : IRasterRenderGraphBuilder, IComputeRenderGraphBuilder
+{
+    private RenderGraph _graph = null!;
+    private RenderGraphPassBase _pass = null!;
+    private RenderGraphResourceRegistry _resources = null!;
+    private bool _disposed;
+
+    internal void Init(RenderGraph graph, RenderGraphPassBase pass, RenderGraphResourceRegistry resources)
+    {
+        _graph = graph;
+        _pass = pass;
+        _resources = resources;
+        _disposed = false;
+    }
+
+    private void ThrowIfDisposed()
+    {
+        ObjectDisposedException.ThrowIf(_disposed, this);
+    }
+
+    private Identifier<RGResource> UseResource(Identifier<RGResource> resource, AccessFlags accessFlags)
+    {
+        if (accessFlags.HasFlag(AccessFlags.Read))
+        {
+            _pass.resourceReads.Add(resource);
+            _resources.AddConsumer(resource, _pass.index);
+        }
+
+        if (accessFlags.HasFlag(AccessFlags.Write))
+        {
+            _pass.resourceWrites.Add(resource);
+            _resources.SetProducer(resource, _pass.index);
+        }
+
+        return resource;
+    }
+
+    public void AllowPassCulling(bool value)
+    {
+        _pass.allowCulling = value;
+    }
+
+    public void EnableAsyncCompute(bool value)
+    {
+        _pass.asyncCompute = value;
+    }
+
+    public Identifier<RGTexture> CreateTexture(in TextureDescriptor descriptor)
+    {
+        ThrowIfDisposed();
+
+        var handle = _resources.CreateTexture(descriptor);
+        _pass.resourceCreates.Add(handle.AsResource());
+        _resources.SetProducer(handle.AsResource(), _pass.index);
+        return handle;
+    }
+
+    public Identifier<RGTexture> UseTexture(Identifier<RGTexture> texture, AccessFlags flags)
+    {
+        ThrowIfDisposed();
+
+        return UseResource(texture.AsResource(), flags).AsTexture();
+    }
+
+    public Identifier<RGTexture> UseRandomAccessTexture(Identifier<RGTexture> texture)
+    {
+        ThrowIfDisposed();
+
+        var resource = texture.AsResource();
+        UseResource(resource, AccessFlags.ReadWrite);
+        _pass.randomAccess.Add(resource);
+        return texture;
+    }
+
+    public Identifier<RGBuffer> UseRandomAccessBuffer(Identifier<RGBuffer> buffer)
+    {
+        ThrowIfDisposed();
+
+        var resource = buffer.AsResource();
+        UseResource(resource, AccessFlags.ReadWrite);
+        _pass.randomAccess.Add(resource);
+        return buffer;
+    }
+
+    public void SetColorAttachment(Identifier<RGTexture> texture, int index)
+    {
+        ThrowIfDisposed();
+
+        Debug.Assert(index >= 0 && index < _pass.colorAccess.Length, "Color attachment index out of range.");
+
+        var id = UseTexture(texture, AccessFlags.Write);
+        if (_pass.colorAccess[index].id == id || _pass.colorAccess[index].id.IsInvalid)
+        {
+            _pass.maxColorIndex = Math.Max(_pass.maxColorIndex, index);
+            _pass.colorAccess[index] = new TextureAccess(id, AccessFlags.Write);
+        }
+        else
+        {
+            throw new InvalidOperationException($"Color attachment at index {index} is already set to a different texture.");
+        }
+    }
+
+    public void SetDepthAttachment(Identifier<RGTexture> texture)
+    {
+        ThrowIfDisposed();
+
+        var id = UseTexture(texture, AccessFlags.Write);
+        if (_pass.depthAccess.id == id || _pass.depthAccess.id.IsInvalid)
+        {
+            _pass.depthAccess = new TextureAccess(id, AccessFlags.Write);
+        }
+        else
+        {
+            throw new InvalidOperationException("Depth attachment is already set to a different texture.");
+        }
+    }
+
+    public void SetRenderFunc<TPassData>(Action<TPassData, RasterRenderContext> renderFunc)
+        where TPassData : class, new()
+    {
+        ((RasterRenderGraphPass<TPassData>)_pass).renderFunc = renderFunc;
+    }
+
+    public void SetRenderFunc<TPassData>(Action<TPassData, ComputeRenderContext> renderFunc)
+        where TPassData : class, new()
+    {
+        ((ComputeRenderGraphPass<TPassData>)_pass).renderFunc = renderFunc;
+    }
+
+    public void Dispose()
+    {
+        if (_disposed)
+        {
+            return;
+        }
+
+        if (!_pass.HasRenderFunc())
+        {
+            throw new InvalidOperationException("RenderGraphBuilder must be disposed after setting up the render function.");
+        }
+
+        _graph = null!;
+        _pass = null!;
+        _resources = null!;
+
+        _disposed = true;
+    }
+}

Ghost.RenderGraph.Concept/RenderGraphPass.cs

@@ -1,5 +1,4 @@
 using Ghost.Core;
-using System.IO;
 
 namespace Ghost.RenderGraph.Concept;
 
@@ -31,14 +30,24 @@ internal abstract class RenderGraphPassBase
     public List<Identifier<RGResource>> randomAccess = new(8);
 
     // Resource dependencies
-    public readonly List<Identifier<RGResource>> resourceReads = new(8);
+    public readonly List<Identifier<RGResource>>[] resourceReads = new List<Identifier<RGResource>>[(int)RenderGraphResourceType.Count];
-    public readonly List<Identifier<RGResource>> resourceWrites = new(4);
+    public readonly List<Identifier<RGResource>>[] resourceWrites = new List<Identifier<RGResource>>[(int)RenderGraphResourceType.Count];
-    public readonly List<Identifier<RGResource>> resourceCreates = new(4);
+    public readonly List<Identifier<RGResource>>[] resourceCreates = new List<Identifier<RGResource>>[(int)RenderGraphResourceType.Count];
 
     // Execution state
     public bool culled;
     public bool hasSideEffects;
 
+    public RenderGraphPassBase()
+    {
+        for (int i = 0; i < (int)RenderGraphResourceType.Count; i++)
+        {
+            resourceReads[i] = new List<Identifier<RGResource>>(8);
+            resourceWrites[i] = new List<Identifier<RGResource>>(4);
+            resourceCreates[i] = new List<Identifier<RGResource>>(4);
+        }
+    }
+
     public abstract void Execute(RenderContext context);
     public abstract void Clear();
     public abstract bool HasRenderFunc();
@@ -57,9 +66,13 @@ internal abstract class RenderGraphPassBase
 
         randomAccess.Clear();
 
-        resourceReads.Clear();
+        for (var i = 0; i < (int)RenderGraphResourceType.Count; i++)
-        resourceWrites.Clear();
+        {
-        resourceCreates.Clear();
+            resourceReads[i].Clear();
+            resourceWrites[i].Clear();
+            resourceCreates[i].Clear();
+        }
+
         culled = false;
         hasSideEffects = false;
     }

Ghost.RenderGraph.Concept/RenderGraphPass.cs.bak

@@ -0,0 +1,129 @@
+using Ghost.Core;
+using System.IO;
+
+namespace Ghost.RenderGraph.Concept;
+
+/// <summary>
+/// Represents different types of render passes.
+/// </summary>
+public enum RenderPassType : byte
+{
+    Raster,
+    Compute
+}
+
+/// <summary>
+/// Base class for render passes.
+/// Uses pooling to avoid allocations after the first frame.
+/// </summary>
+internal abstract class RenderGraphPassBase
+{
+    public string name = string.Empty;
+    public int index;
+    public RenderPassType type;
+    public bool allowCulling = true;
+    public bool asyncCompute;
+
+    public TextureAccess depthAccess;
+    public TextureAccess[] colorAccess = new TextureAccess[8];
+    public int maxColorIndex = -1;
+
+    public List<Identifier<RGResource>> randomAccess = new(8);
+
+    // Resource dependencies
+    public readonly List<Identifier<RGResource>> resourceReads = new(8);
+    public readonly List<Identifier<RGResource>> resourceWrites = new(4);
+    public readonly List<Identifier<RGResource>> resourceCreates = new(4);
+    
+    // Execution state
+    public bool culled;
+    public bool hasSideEffects;
+
+    public abstract void Execute(RenderContext context);
+    public abstract void Clear();
+    public abstract bool HasRenderFunc();
+
+    public virtual void Reset(RenderGraphObjectPool pool)
+    {
+        name = string.Empty;
+        index = -1;
+        type = RenderPassType.Raster;
+        allowCulling = true;
+        asyncCompute = false;
+        
+        depthAccess = default;
+        colorAccess.AsSpan().Clear();
+        maxColorIndex = -1;
+
+        randomAccess.Clear();
+
+        resourceReads.Clear();
+        resourceWrites.Clear();
+        resourceCreates.Clear();
+        culled = false;
+        hasSideEffects = false;
+    }
+}
+
+internal abstract class RenderGraphPassT<TPassData, TRenderContext> : RenderGraphPassBase
+    where TPassData : class, new()
+{
+    public TPassData passData = null!;
+    public Action<TPassData, TRenderContext>? renderFunc;
+
+    public void Init(int index, TPassData passData, string name, RenderPassType type)
+    {
+        this.index = index;
+        this.passData = passData;
+        this.name = name;
+        this.type = type;
+    }
+
+    public sealed override bool HasRenderFunc()
+    {
+        return renderFunc != null;
+    }
+
+    public override void Clear()
+    {
+        passData = null!;
+        renderFunc = null;
+    }
+
+    public override void Reset(RenderGraphObjectPool pool)
+    {
+        base.Reset(pool);
+        pool.Return(passData);
+        Clear();
+    }
+}
+
+internal sealed class RasterRenderGraphPass<TPassData> : RenderGraphPassT<TPassData, RasterRenderContext>
+    where TPassData : class, new()
+{
+    public override void Execute(RenderContext context)
+    {
+        renderFunc!(passData, context.RasterContext);
+    }
+
+    public override void Reset(RenderGraphObjectPool pool)
+    {
+        base.Reset(pool);
+        pool.Return(this);
+    }
+}
+
+internal sealed class ComputeRenderGraphPass<TPassData> : RenderGraphPassT<TPassData, ComputeRenderContext>
+    where TPassData : class, new()
+{
+    public override void Execute(RenderContext context)
+    {
+        renderFunc!(passData, context.ComputeContext);
+    }
+
+    public override void Reset(RenderGraphObjectPool pool)
+    {
+        base.Reset(pool);
+        pool.Return(this);
+    }
+}

Ghost.RenderGraph.Concept/RenderGraphTypes.cs

@@ -3,11 +3,11 @@ using System.Runtime.CompilerServices;
 
 namespace Ghost.RenderGraph.Concept;
 
-internal enum RenderGraphResourceType
+internal enum RenderGraphResourceType : int
 {
     Texture,
     Buffer,
-    AccelerationStructure,
+    // AccelerationStructure,
     Count
 }
 
@@ -84,14 +84,79 @@ public readonly struct TextureDescriptor : IEquatable<TextureDescriptor>
         this.name = name;
     }
 
-    public readonly bool Equals(TextureDescriptor other) =>
+    public readonly bool Equals(TextureDescriptor other)
-        width == other.width &&
+    {
+        return width == other.width &&
         height == other.height &&
         format == other.format &&
         name == other.name;
+    }
 
     public override readonly bool Equals(object? obj) => obj is TextureDescriptor other && Equals(other);
     public override readonly int GetHashCode() => HashCode.Combine(width, height, format, name);
+
+    public static bool operator ==(TextureDescriptor left, TextureDescriptor right)
+    {
+        return left.Equals(right);
+    }
+
+    public static bool operator !=(TextureDescriptor left, TextureDescriptor right)
+    {
+        return !(left == right);
+    }
+}
+
+[Flags]
+public enum BufferUsage
+{
+    None = 0,
+    Vertex = 1 << 0,
+    Index = 1 << 1,
+    IndirectArgument = 1 << 7,
+    Constant = 1 << 2,
+    ShaderResource = 1 << 3,
+    UnorderedAccess = 1 << 4,
+    Structured = 1 << 5,
+    Raw = 1 << 6,
+    Upload = 1 << 8,
+    Readback = 1 << 9,
+}
+
+public readonly struct BufferDescriptor : IEquatable<BufferDescriptor>
+{
+    public readonly uint sizeInBytes;
+    public readonly uint stride;
+    public readonly BufferUsage usage;
+    public readonly string name;
+
+    public BufferDescriptor(uint sizeInBytes, uint stride, BufferUsage usage, string name)
+    {
+        this.sizeInBytes = sizeInBytes;
+        this.stride = stride;
+        this.usage = usage;
+        this.name = name;
+    }
+
+    public readonly bool Equals(BufferDescriptor other)
+    {
+        return sizeInBytes == other.sizeInBytes &&
+               stride == other.stride &&
+               usage == other.usage &&
+               name == other.name;
+    }
+
+    public override readonly bool Equals(object? obj) => obj is BufferDescriptor other && Equals(other);
+    public override readonly int GetHashCode() => HashCode.Combine(sizeInBytes, name);
+
+    public static bool operator ==(BufferDescriptor left, BufferDescriptor right)
+    {
+        return left.Equals(right);
+    }
+
+    public static bool operator !=(BufferDescriptor left, BufferDescriptor right)
+    {
+        return !(left == right);
+    }
 }
 
 /// <summary>