Enhance OpenGLBuffer with more buffer types and features

- Add OpenGLBufferType enum (Vertex, Index, Uniform, CopyRead, CopyWrite, etc.)
- Add Initialize() method with buffer type parameter
- Add Map/Unmap for direct buffer access
- Add SetData for dynamic updates
- Add BindBase for buffer binding to indexed targets
- Add GetType and IsDynamic getters

engine/include/XCEngine/RHI/OpenGL/OpenGLBuffer.h

@@ -6,25 +6,47 @@
 namespace XCEngine {
 namespace RHI {
 
+enum class OpenGLBufferType {
+    Vertex,
+    Index,
+    Uniform,
+    CopyRead,
+    CopyWrite,
+    AtomicCounter,
+    DispatchIndirect,
+    DrawIndirect,
+    ShaderBindingTable
+};
+
 class OpenGLBuffer {
 public:
     OpenGLBuffer();
     ~OpenGLBuffer();
 
+    bool Initialize(OpenGLBufferType type, size_t size, const void* data = nullptr, bool dynamic = false);
     bool InitializeVertexBuffer(const void* data, size_t size);
     bool InitializeIndexBuffer(const void* data, size_t size);
     void Shutdown();
 
     void Bind() const;
     void Unbind() const;
+    void BindBase(unsigned int target, unsigned int index) const;
+
+    void* Map();
+    void Unmap();
+    void SetData(const void* data, size_t size, size_t offset = 0);
 
     unsigned int GetID() const { return m_buffer; }
     size_t GetSize() const { return m_size; }
+    OpenGLBufferType GetType() const { return m_type; }
+    bool IsDynamic() const { return m_dynamic; }
 
 private:
     unsigned int m_buffer;
     size_t m_size;
     bool m_isIndexBuffer;
+    bool m_dynamic;
+    OpenGLBufferType m_type;
 };
 
 } // namespace RHI

engine/src/RHI/OpenGL/OpenGLBuffer.cpp

@@ -6,32 +6,56 @@
 namespace XCEngine {
 namespace RHI {
 
+static unsigned int ToGLBufferTarget(OpenGLBufferType type) {
+    switch (type) {
+        case OpenGLBufferType::Vertex: return GL_ARRAY_BUFFER;
+        case OpenGLBufferType::Index: return GL_ELEMENT_ARRAY_BUFFER;
+        case OpenGLBufferType::Uniform: return GL_UNIFORM_BUFFER;
+        case OpenGLBufferType::CopyRead: return GL_COPY_READ_BUFFER;
+        case OpenGLBufferType::CopyWrite: return GL_COPY_WRITE_BUFFER;
+        case OpenGLBufferType::AtomicCounter: return GL_ATOMIC_COUNTER_BUFFER;
+        case OpenGLBufferType::DispatchIndirect: return GL_DISPATCH_INDIRECT_BUFFER;
+        case OpenGLBufferType::DrawIndirect: return GL_DRAW_INDIRECT_BUFFER;
+        case OpenGLBufferType::ShaderBindingTable: return GL_SHADER_STORAGE_BUFFER;
+        default: return GL_ARRAY_BUFFER;
+    }
+}
+
 OpenGLBuffer::OpenGLBuffer()
     : m_buffer(0)
     , m_size(0)
-    , m_isIndexBuffer(false) {
+    , m_isIndexBuffer(false)
+    , m_dynamic(false)
+    , m_type(OpenGLBufferType::Vertex) {
 }
 
 OpenGLBuffer::~OpenGLBuffer() {
     Shutdown();
 }
 
-bool OpenGLBuffer::InitializeVertexBuffer(const void* data, size_t size) {
-    glGenBuffers(1, &m_buffer);
-    glBindBuffer(GL_ARRAY_BUFFER, m_buffer);
-    glBufferData(GL_ARRAY_BUFFER, size, data, GL_STATIC_DRAW);
+bool OpenGLBuffer::Initialize(OpenGLBufferType type, size_t size, const void* data, bool dynamic) {
+    m_type = type;
     m_size = size;
-    m_isIndexBuffer = false;
+    m_dynamic = dynamic;
+    m_isIndexBuffer = (type == OpenGLBufferType::Index);
+
+    unsigned int target = ToGLBufferTarget(type);
+    GLenum usage = dynamic ? GL_DYNAMIC_DRAW : GL_STATIC_DRAW;
+
+    glGenBuffers(1, &m_buffer);
+    glBindBuffer(target, m_buffer);
+    glBufferData(target, size, data, usage);
+    glBindBuffer(target, 0);
+
     return true;
 }
 
+bool OpenGLBuffer::InitializeVertexBuffer(const void* data, size_t size) {
+    return Initialize(OpenGLBufferType::Vertex, size, data, false);
+}
+
 bool OpenGLBuffer::InitializeIndexBuffer(const void* data, size_t size) {
-    glGenBuffers(1, &m_buffer);
-    glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, m_buffer);
-    glBufferData(GL_ELEMENT_ARRAY_BUFFER, size, data, GL_STATIC_DRAW);
-    m_size = size;
-    m_isIndexBuffer = true;
-    return true;
+    return Initialize(OpenGLBufferType::Index, size, data, false);
 }
 
 void OpenGLBuffer::Shutdown() {
@@ -42,19 +66,43 @@ void OpenGLBuffer::Shutdown() {
 }
 
 void OpenGLBuffer::Bind() const {
-    if (m_isIndexBuffer) {
-        glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, m_buffer);
-    } else {
-        glBindBuffer(GL_ARRAY_BUFFER, m_buffer);
-    }
+    unsigned int target = ToGLBufferTarget(m_type);
+    glBindBuffer(target, m_buffer);
 }
 
 void OpenGLBuffer::Unbind() const {
-    if (m_isIndexBuffer) {
-        glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
-    } else {
-        glBindBuffer(GL_ARRAY_BUFFER, 0);
+    unsigned int target = ToGLBufferTarget(m_type);
+    glBindBuffer(target, 0);
 }
+
+void OpenGLBuffer::BindBase(unsigned int target, unsigned int index) const {
+    glBindBufferBase(target, index, m_buffer);
+}
+
+void* OpenGLBuffer::Map() {
+    unsigned int target = ToGLBufferTarget(m_type);
+    glBindBuffer(target, m_buffer);
+    void* ptr = glMapBuffer(target, GL_WRITE_ONLY);
+    glBindBuffer(target, 0);
+    return ptr;
+}
+
+void OpenGLBuffer::Unmap() {
+    unsigned int target = ToGLBufferTarget(m_type);
+    glBindBuffer(target, m_buffer);
+    glUnmapBuffer(target);
+    glBindBuffer(target, 0);
+}
+
+void OpenGLBuffer::SetData(const void* data, size_t size, size_t offset) {
+    unsigned int target = ToGLBufferTarget(m_type);
+    glBindBuffer(target, m_buffer);
+    if (offset == 0 && size == m_size) {
+        glBufferData(target, size, data, m_dynamic ? GL_DYNAMIC_DRAW : GL_STATIC_DRAW);
+    } else {
+        glBufferSubData(target, offset, size, data);
+    }
+    glBindBuffer(target, 0);
 }
 
 } // namespace RHI