refactor(RHI): 完成 Shader uniform 设置迁移到 CommandList

- 删除 RHIShader 的 OpenGL 风格 SetMat4/SetVec3/SetInt 等方法
- 添加 UniformInfo 结构体和 GetUniformInfos/GetUniformInfo 接口
- D3D12Shader 和 OpenGLShader 实现 CacheUniformInfos
- RHICommandList 添加 SetUniform*/SetGlobal* 统一接口
- D3D12 实现 D3D12PipelineLayout 管理 root signature 映射
- 修复 D3D12CommandList::SetPipelineStateInternal 在 Reset 后未重新应用 root signature 的问题
- 更新 OpenGL 集成测试使用新的 SetUniform* API
- 所有单元测试和集成测试通过 (8/8 integration tests)

engine/src/RHI/D3D12/D3D12Shader.cpp

@@ -1,11 +1,15 @@
 #include "XCEngine/RHI/D3D12/D3D12Shader.h"
 #include <d3dcompiler.h>
 
+static const IID IID_ID3D12ShaderReflection = {
+    0x8e5c5a69, 0x5c6a, 0x427d, {0xb0, 0xdc, 0x27, 0x63, 0xae, 0xac, 0xe3, 0x75}
+};
+
 namespace XCEngine {
 namespace RHI {
 
 D3D12Shader::D3D12Shader()
-    : m_type(ShaderType::Vertex) {
+    : m_type(ShaderType::Vertex), m_uniformsCached(false) {
 }
 
 D3D12Shader::~D3D12Shader() {
@@ -35,6 +39,7 @@ bool D3D12Shader::CompileFromFile(const wchar_t* filePath, const char* entryPoin
         m_type = ShaderType::Compute;
     }
 
+    m_uniformsCached = false;
     return true;
 }
 
@@ -50,12 +55,87 @@ bool D3D12Shader::Compile(const void* sourceData, size_t sourceSize, const char*
         return false;
     }
 
+    m_uniformsCached = false;
     return true;
 }
 
 void D3D12Shader::Shutdown() {
     m_bytecode.Reset();
     m_error.Reset();
+    m_uniformInfos.clear();
+    m_uniformsCached = false;
+}
+
+void D3D12Shader::CacheUniformInfos() const {
+    if (m_uniformsCached || !m_bytecode) {
+        return;
+    }
+    
+    m_uniformInfos.clear();
+    
+    ComPtr<ID3D12ShaderReflection> pReflection;
+    HRESULT hr = D3DReflect(m_bytecode->GetBufferPointer(), m_bytecode->GetBufferSize(),
+        IID_ID3D12ShaderReflection, (void**)&pReflection);
+    
+    if (FAILED(hr)) {
+        return;
+    }
+    
+    D3D12_SHADER_DESC shaderDesc;
+    pReflection->GetDesc(&shaderDesc);
+    
+    for (UINT i = 0; i < shaderDesc.BoundResources; ++i) {
+        D3D12_SHADER_INPUT_BIND_DESC bindDesc;
+        pReflection->GetResourceBindingDesc(i, &bindDesc);
+        
+        UniformInfo info;
+        info.name = bindDesc.Name;
+        info.bindPoint = bindDesc.BindPoint;
+        info.arraySize = bindDesc.NumSamples;
+        
+        switch (bindDesc.Type) {
+            case D3D_SIT_CBUFFER:
+                info.type = static_cast<uint32_t>(D3D_SIT_CBUFFER);
+                break;
+            case D3D_SIT_TEXTURE:
+                info.type = static_cast<uint32_t>(D3D_SIT_TEXTURE);
+                break;
+            case D3D_SIT_SAMPLER:
+                info.type = static_cast<uint32_t>(D3D_SIT_SAMPLER);
+                break;
+            default:
+                info.type = static_cast<uint32_t>(bindDesc.Type);
+                break;
+        }
+        
+        D3D12_SHADER_BUFFER_DESC bufferDesc;
+        if (bindDesc.Type == D3D_SIT_CBUFFER) {
+            ID3D12ShaderReflectionConstantBuffer* pCB = pReflection->GetConstantBufferByIndex(bindDesc.BindPoint);
+            pCB->GetDesc(&bufferDesc);
+            info.size = bufferDesc.Size;
+        } else {
+            info.size = 0;
+        }
+        
+        m_uniformInfos.push_back(info);
+    }
+    
+    m_uniformsCached = true;
+}
+
+const std::vector<RHIShader::UniformInfo>& D3D12Shader::GetUniformInfos() const {
+    CacheUniformInfos();
+    return m_uniformInfos;
+}
+
+const RHIShader::UniformInfo* D3D12Shader::GetUniformInfo(const char* name) const {
+    CacheUniformInfos();
+    for (const auto& info : m_uniformInfos) {
+        if (info.name == name) {
+            return &info;
+        }
+    }
+    return nullptr;
 }
 
 const D3D12_SHADER_BYTECODE D3D12Shader::GetD3D12Bytecode() const {
@@ -90,4 +170,4 @@ ShaderType D3D12Shader::GetType() const {
 }
 
 } // namespace RHI
-} // namespace XCEngine
+} // namespace XCEngine