Add OpenGL backend core classes: Buffer, VertexArray

- Added OpenGLBuffer class for VBO/IBO management
- Added OpenGLVertexArray class for VAO management
- Updated CMakeLists.txt to include new source files

tests/OpenGL/CMakeLists.txt

@@ -26,6 +26,8 @@ add_executable(
   main.cpp
   OpenGLDevice.cpp
   OpenGLShader.cpp
+  OpenGLBuffer.cpp
+  OpenGLVertexArray.cpp
   ./package/src/glad.c
 )
 

tests/OpenGL/OpenGLBuffer.cpp

@@ -0,0 +1,61 @@
+#define GLFW_INCLUDE_NONE
+#include "OpenGLBuffer.h"
+#include <glad/glad.h>
+#include <GLFW/glfw3.h>
+
+namespace XCEngine {
+namespace RHI {
+
+OpenGLBuffer::OpenGLBuffer()
+    : m_buffer(0)
+    , m_size(0)
+    , m_isIndexBuffer(false) {
+}
+
+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);
+    m_size = size;
+    m_isIndexBuffer = false;
+    return true;
+}
+
+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;
+}
+
+void OpenGLBuffer::Shutdown() {
+    if (m_buffer) {
+        glDeleteBuffers(1, &m_buffer);
+        m_buffer = 0;
+    }
+}
+
+void OpenGLBuffer::Bind() const {
+    if (m_isIndexBuffer) {
+        glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, m_buffer);
+    } else {
+        glBindBuffer(GL_ARRAY_BUFFER, m_buffer);
+    }
+}
+
+void OpenGLBuffer::Unbind() const {
+    if (m_isIndexBuffer) {
+        glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
+    } else {
+        glBindBuffer(GL_ARRAY_BUFFER, 0);
+    }
+}
+
+} // namespace RHI
+} // namespace XCEngine

tests/OpenGL/OpenGLBuffer.h

@@ -0,0 +1,31 @@
+#pragma once
+
+#include <string>
+#include <GLFW/glfw3.h>
+
+namespace XCEngine {
+namespace RHI {
+
+class OpenGLBuffer {
+public:
+    OpenGLBuffer();
+    ~OpenGLBuffer();
+
+    bool InitializeVertexBuffer(const void* data, size_t size);
+    bool InitializeIndexBuffer(const void* data, size_t size);
+    void Shutdown();
+
+    void Bind() const;
+    void Unbind() const;
+
+    unsigned int GetID() const { return m_buffer; }
+    size_t GetSize() const { return m_size; }
+
+private:
+    unsigned int m_buffer;
+    size_t m_size;
+    bool m_isIndexBuffer;
+};
+
+} // namespace RHI
+} // namespace XCEngine

tests/OpenGL/OpenGLVertexArray.cpp

@@ -0,0 +1,60 @@
+#define GLFW_INCLUDE_NONE
+#include "OpenGLVertexArray.h"
+#include <glad/glad.h>
+#include <GLFW/glfw3.h>
+
+namespace XCEngine {
+namespace RHI {
+
+OpenGLVertexArray::OpenGLVertexArray()
+    : m_vao(0)
+    , m_indexBuffer(0)
+    , m_indexCount(0)
+    , m_vertexBufferCount(0) {
+}
+
+OpenGLVertexArray::~OpenGLVertexArray() {
+    Shutdown();
+}
+
+bool OpenGLVertexArray::Initialize() {
+    glGenVertexArrays(1, &m_vao);
+    return true;
+}
+
+void OpenGLVertexArray::AddVertexBuffer(unsigned int buffer, const VertexAttribute& attribute) {
+    glBindVertexArray(m_vao);
+    glBindBuffer(GL_ARRAY_BUFFER, buffer);
+    glEnableVertexAttribArray(attribute.index);
+    glVertexAttribPointer(attribute.index, attribute.count, attribute.type, 
+        attribute.normalized ? GL_TRUE : GL_FALSE, 
+        attribute.stride, (void*)attribute.offset);
+    glBindBuffer(GL_ARRAY_BUFFER, 0);
+    glBindVertexArray(0);
+    m_vertexBufferCount++;
+}
+
+void OpenGLVertexArray::SetIndexBuffer(unsigned int buffer, unsigned int type) {
+    glBindVertexArray(m_vao);
+    glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, buffer);
+    glBindVertexArray(0);
+    m_indexBuffer = buffer;
+}
+
+void OpenGLVertexArray::Shutdown() {
+    if (m_vao) {
+        glDeleteVertexArrays(1, &m_vao);
+        m_vao = 0;
+    }
+}
+
+void OpenGLVertexArray::Bind() const {
+    glBindVertexArray(m_vao);
+}
+
+void OpenGLVertexArray::Unbind() const {
+    glBindVertexArray(0);
+}
+
+} // namespace RHI
+} // namespace XCEngine

tests/OpenGL/OpenGLVertexArray.h

@@ -0,0 +1,44 @@
+#pragma once
+
+#include <string>
+#include <GLFW/glfw3.h>
+#include <vector>
+
+namespace XCEngine {
+namespace RHI {
+
+struct VertexAttribute {
+    unsigned int index;
+    int count;
+    unsigned int type;
+    bool normalized;
+    size_t stride;
+    size_t offset;
+};
+
+class OpenGLVertexArray {
+public:
+    OpenGLVertexArray();
+    ~OpenGLVertexArray();
+
+    bool Initialize();
+    void AddVertexBuffer(unsigned int buffer, const VertexAttribute& attribute);
+    void SetIndexBuffer(unsigned int buffer, unsigned int type);
+    void Shutdown();
+
+    void Bind() const;
+    void Unbind() const;
+
+    unsigned int GetID() const { return m_vao; }
+    unsigned int GetIndexBuffer() const { return m_indexBuffer; }
+    unsigned int GetIndexCount() const { return m_indexCount; }
+
+private:
+    unsigned int m_vao;
+    unsigned int m_indexBuffer;
+    unsigned int m_indexCount;
+    int m_vertexBufferCount;
+};
+
+} // namespace RHI
+} // namespace XCEngine