feat(RHI): 实现 RHICommandList 抽象基类

docs/RHI抽象层设计与实现.md

@@ -760,6 +760,84 @@ public:
    - 解决：GetNativeHandle() 返回 void*
 
 
+### 5.12 命令列表（RHICommandList）抽象设计
+
+#### 5.12.1 设计理念对应
+
+| 差异点 | 设计理念 | 处理方案 |
+|--------|---------|---------|
+| 资源状态转换 | 特性降级 | D3D12 实现转换，OpenGL 空实现 |
+| 绑定方式 | 求同存异 | 统一接口，后端各自实现 |
+| 渲染目标 | 求同存异 | 统一接口，后端各自实现 |
+
+#### 5.12.2 现有实现对比
+
+| 功能 | D3D12CommandList | OpenGLCommandList | 处理方案 |
+|------|-------------------|-------------------|----------|
+| 资源转换 | TransitionBarrier | glBarrier | 统一 TransitionBarrier |
+| PSO 设置 | SetPipelineState | UseShader | 统一 SetPipelineState |
+| 视口/裁剪 | SetViewport/ScissorRect | SetViewport/Scissor | 统一 |
+| 顶点缓冲 | SetVertexBuffer | BindVertexArray | 统一 |
+| 索引缓冲 | SetIndexBuffer | BindVertexArray | 统一 |
+| 绘制 | Draw/DrawIndexed | Draw/DrawIndexed | 统一 |
+| 渲染目标 | SetRenderTargets | glBindFramebuffer | 统一 |
+| 清除 | ClearRenderTargetView | Clear | 统一 |
+| 复制 | CopyResource | CopyImageSubData | 统一 |
+| 计算 | Dispatch | DispatchCompute | 统一 |
+
+#### 5.12.3 抽象接口定义
+
+```cpp
+class RHICommandList {
+public:
+    virtual ~RHICommandList() = default;
+
+    virtual void Shutdown() = 0;
+
+    virtual void Reset() = 0;
+    virtual void Close() = 0;
+
+    virtual void TransitionBarrier(void* resource, ResourceStates stateBefore, ResourceStates stateAfter) = 0;
+
+    virtual void SetPipelineState(void* pso) = 0;
+    virtual void SetViewport(const Viewport& viewport) = 0;
+    virtual void SetScissorRect(const Rect& rect) = 0;
+    virtual void SetRenderTargets(uint32_t count, void** renderTargets, void* depthStencil = nullptr) = 0;
+
+    virtual void SetVertexBuffer(uint32_t slot, void* buffer, uint64_t offset, uint32_t stride) = 0;
+    virtual void SetIndexBuffer(void* buffer, uint64_t offset, Format format) = 0;
+
+    virtual void Draw(uint32_t vertexCount, uint32_t instanceCount = 1, uint32_t startVertex = 0, uint32_t startInstance = 0) = 0;
+    virtual void DrawIndexed(uint32_t indexCount, uint32_t instanceCount = 1, uint32_t startIndex = 0, int32_t baseVertex = 0, uint32_t startInstance = 0) = 0;
+
+    virtual void Clear(float r, float g, float b, float a, uint32_t buffers) = 0;
+    virtual void ClearRenderTarget(void* renderTarget, const float color[4]) = 0;
+    virtual void ClearDepthStencil(void* depthStencil, float depth, uint8_t stencil) = 0;
+
+    virtual void CopyResource(void* dst, void* src) = 0;
+
+    virtual void Dispatch(uint32_t x, uint32_t y, uint32_t z) = 0;
+};
+```
+
+#### 5.12.4 差异处理策略
+
+1. **资源状态转换（特性降级）**
+   - D3D12：显式 TransitionBarrier 管理资源状态
+   - OpenGL：无资源状态概念
+   - 解决：D3D12 实现转换，OpenGL 空实现
+
+2. **绑定方式（求同存异）**
+   - D3D12：通过 DescriptorHeap 和 RootSignature
+   - OpenGL：通过 glBind* 和 VAO
+   - 解决：统一 Set* 接口，后端各自实现
+
+3. **渲染目标（求同存异）**
+   - D3D12：SetRenderTargets 设置渲染目标视图
+   - OpenGL：glBindFramebuffer 绑定帧缓冲
+   - 解决：统一 SetRenderTargets 接口
+
+
 ## 6. 后端实现示例
 ### 6.1 D3D12 设备实现（D3D12Device.h）
 ```cpp