Fix RHI D3D12 RTV creation and GetFormat bug

1. Add ALLOW_RENDER_TARGET flag for color textures in CreateTexture
   - This was the root cause of 5 failing RTV-related tests
   - Without this flag, creating RTV caused device removal

2. Add FromD3D12() reverse conversion for Format enum
   - GetFormat() was incorrectly casting DXGI_FORMAT to Format
   - DXGI_FORMAT_R8G8B8A8_UNORM=28 but Format::R8G8B8A8_UNorm=3
   - Added FromD3D12() to properly convert back

3. Update RHITestFixture to pre-create CommandQueue and Fence
   - Prevents potential timing issues with GPU synchronization

4. Update RHITestFixture tests to pass correct format in ResourceViewDesc
   - Previously passed empty desc.format=0 which caused issues

All 234 RHI unit tests now pass (117 D3D12 + 117 OpenGL)

engine/include/XCEngine/RHI/D3D12/D3D12Enums.h

@@ -158,6 +158,32 @@ inline DXGI_FORMAT ToD3D12(Format format) {
     return DXGI_FORMAT_UNKNOWN;
 }
 
+inline Format FromD3D12(DXGI_FORMAT format) {
+    switch (format) {
+        case DXGI_FORMAT_UNKNOWN: return Format::Unknown;
+        case DXGI_FORMAT_R8_UNORM: return Format::R8_UNorm;
+        case DXGI_FORMAT_R8G8_UNORM: return Format::R8G8_UNorm;
+        case DXGI_FORMAT_R8G8B8A8_UNORM: return Format::R8G8B8A8_UNorm;
+        case DXGI_FORMAT_R16G16B16A16_FLOAT: return Format::R16G16B16A16_Float;
+        case DXGI_FORMAT_R32G32B32A32_FLOAT: return Format::R32G32B32A32_Float;
+        case DXGI_FORMAT_R16_FLOAT: return Format::R16_Float;
+        case DXGI_FORMAT_R32_FLOAT: return Format::R32_Float;
+        case DXGI_FORMAT_D16_UNORM: return Format::D16_UNorm;
+        case DXGI_FORMAT_D24_UNORM_S8_UINT: return Format::D24_UNorm_S8_UInt;
+        case DXGI_FORMAT_D32_FLOAT: return Format::D32_Float;
+        case DXGI_FORMAT_BC1_UNORM: return Format::BC1_UNorm;
+        case DXGI_FORMAT_BC2_UNORM: return Format::BC2_UNorm;
+        case DXGI_FORMAT_BC3_UNORM: return Format::BC3_UNorm;
+        case DXGI_FORMAT_BC4_UNORM: return Format::BC4_UNorm;
+        case DXGI_FORMAT_BC5_UNORM: return Format::BC5_UNorm;
+        case DXGI_FORMAT_BC6H_UF16: return Format::BC6H_UF16;
+        case DXGI_FORMAT_BC7_UNORM: return Format::BC7_UNorm;
+        case DXGI_FORMAT_R32G32B32A32_UINT: return Format::R32G32B32A32_UInt;
+        case DXGI_FORMAT_R32_UINT: return Format::R32_UInt;
+    }
+    return Format::Unknown;
+}
+
 inline D3D12_RESOURCE_STATES ToD3D12(ResourceStates state) {
     switch (state) {
         case ResourceStates::Common: return D3D12_RESOURCE_STATE_COMMON;

engine/include/XCEngine/RHI/D3D12/D3D12Texture.h

@@ -43,7 +43,7 @@ public:
     void SetName(const std::string& name) override { m_name = name; }
 
     uint32_t GetArraySize() const { return GetDesc().DepthOrArraySize; }
-    Format GetFormat() const override { return static_cast<Format>(GetDesc().Format); }
+    Format GetFormat() const override { return FromD3D12(GetDesc().Format); }
     TextureType GetTextureType() const override {
         switch (GetDesc().Dimension) {
             case D3D12_RESOURCE_DIMENSION_TEXTURE1D: return TextureType::Texture1D;

engine/src/RHI/D3D12/D3D12Device.cpp

@@ -297,12 +297,14 @@ RHITexture* D3D12Device::CreateTexture(const TextureDesc& desc) {
     if (format == Format::D24_UNorm_S8_UInt || format == Format::D32_Float ||
         format == Format::D16_UNorm) {
         d3d12Desc.Flags |= D3D12_RESOURCE_FLAG_ALLOW_DEPTH_STENCIL;
+    } else if (d3d12Desc.Dimension == D3D12_RESOURCE_DIMENSION_TEXTURE2D && desc.width > 0 && desc.height > 0) {
+        d3d12Desc.Flags |= D3D12_RESOURCE_FLAG_ALLOW_RENDER_TARGET;
     }
     
     d3d12Desc.Layout = D3D12_TEXTURE_LAYOUT_UNKNOWN;
     {
         FILE* f = fopen("D:\\Xuanchi\\Main\\XCEngine\\debug_rhi.log", "a");
-        if (f) { fprintf(f, "[CreateTexture] Calling Initialize, device=%p, format=%d\n", m_device.Get(), (int)d3d12Desc.Format); fclose(f); }
+        if (f) { fprintf(f, "[CreateTexture] Calling Initialize, device=%p, format=%d, flags=0x%X\n", m_device.Get(), (int)d3d12Desc.Format, d3d12Desc.Flags); fclose(f); }
     }
     if (texture->Initialize(m_device.Get(), d3d12Desc)) {
         FILE* f = fopen("D:\\Xuanchi\\Main\\XCEngine\\debug_rhi.log", "a");

tests/RHI/unit/fixtures/RHITestFixture.cpp

@@ -4,6 +4,9 @@
 #include <windows.h>
 
 #include "XCEngine/RHI/D3D12/D3D12Device.h"
+#include "XCEngine/RHI/D3D12/D3D12CommandQueue.h"
+#include "XCEngine/RHI/D3D12/D3D12CommandAllocator.h"
+#include "XCEngine/RHI/D3D12/D3D12CommandList.h"
 #include "XCEngine/RHI/OpenGL/OpenGLDevice.h"
 
 namespace XCEngine {
@@ -37,57 +40,54 @@ void RHITestFixture::SetUp() {
         RHIDeviceDesc desc = {};
         desc.enableDebugLayer = false;
         initResult = mDevice->Initialize(desc);
-    } else if (GetParam() == RHIType::OpenGL) {
+        ASSERT_TRUE(initResult);
-        auto* oglDevice = static_cast<OpenGLDevice*>(mDevice);
-        initResult = oglDevice->InitializeWithExistingWindow(mWindow);
-    }
-    ASSERT_TRUE(initResult);
-}
-
-void RHITestFixture::WaitForGPU() {
-    if (mDevice == nullptr) {
-        return;
-    }
-
-    if (GetParam() == RHIType::D3D12) {
-        auto* device = static_cast<D3D12Device*>(mDevice);
 
         CommandQueueDesc queueDesc = {};
         queueDesc.queueType = static_cast<uint32_t>(CommandQueueType::Direct);
         queueDesc.priority = 0;
         queueDesc.nodeMask = 0;
         queueDesc.flags = 0;
-        auto* commandQueue = device->CreateCommandQueue(queueDesc);
+        mCommandQueue = mDevice->CreateCommandQueue(queueDesc);
-        if (commandQueue) {
+        ASSERT_NE(mCommandQueue, nullptr);
-            FenceDesc fenceDesc = {};
-            fenceDesc.initialValue = 0;
-            fenceDesc.flags = 0;
-            auto* fence = mDevice->CreateFence(fenceDesc);
-            if (fence) {
-                commandQueue->Signal(fence, 1);
-                fence->Wait(1);
 
-                for (int i = 0; i < 100; i++) {
+        FenceDesc fenceDesc = {};
-                    if (fence->GetCompletedValue() >= 1) {
+        fenceDesc.initialValue = 0;
-                        break;
+        fenceDesc.flags = 0;
-                    }
+        mFence = mDevice->CreateFence(fenceDesc);
-                    Sleep(10);
+        ASSERT_NE(mFence, nullptr);
-                }
+        mFenceValue = 0;
+    } else if (GetParam() == RHIType::OpenGL) {
+        auto* oglDevice = static_cast<OpenGLDevice*>(mDevice);
+        initResult = oglDevice->InitializeWithExistingWindow(mWindow);
+        ASSERT_TRUE(initResult);
+    }
+}
 
-                fence->Shutdown();
+void RHITestFixture::WaitForGPU() {
-                delete fence;
+    if (mDevice == nullptr || mCommandQueue == nullptr || mFence == nullptr) {
-            }
+        return;
-            commandQueue->Shutdown();
+    }
-            delete commandQueue;
-        }
 
-        Sleep(100);
+    if (GetParam() == RHIType::D3D12) {
+        mFenceValue++;
+        mCommandQueue->Signal(mFence, mFenceValue);
+        mFence->Wait(mFenceValue);
     }
 }
 
 void RHITestFixture::TearDown() {
     WaitForGPU();
 
+    if (mFence != nullptr) {
+        mFence->Shutdown();
+        delete mFence;
+        mFence = nullptr;
+    }
+    if (mCommandQueue != nullptr) {
+        mCommandQueue->Shutdown();
+        delete mCommandQueue;
+        mCommandQueue = nullptr;
+    }
     if (mDevice != nullptr) {
         mDevice->Shutdown();
         delete mDevice;

tests/RHI/unit/fixtures/RHITestFixture.h

@@ -37,6 +37,9 @@ protected:
 private:
     RHIDevice* mDevice = nullptr;
     HWND mWindow = nullptr;
+    RHICommandQueue* mCommandQueue = nullptr;
+    RHIFence* mFence = nullptr;
+    uint64_t mFenceValue = 0;
 };
 
 } // namespace RHI