feat: engine as library

engine/src/renderer/mesh.cpp

@@ -0,0 +1,60 @@
+#include <cstddef>
+
+#include "engine/renderer/mesh.h"
+
+Mesh::Mesh() {
+    m_vao = 0;
+    m_vbo = 0;
+    m_ebo = 0;
+    
+    glGenVertexArrays(1, &m_vao);
+    glGenBuffers(1, &m_vbo);
+    glGenBuffers(1, &m_ebo);
+
+    glBindVertexArray(m_vao);
+
+    // VBO (vertex buffer)
+    glBindBuffer(GL_ARRAY_BUFFER, m_vbo);
+    glBufferData(GL_ARRAY_BUFFER, 0, nullptr, GL_DYNAMIC_DRAW);
+
+    // EBO (index buffer)
+    glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, m_ebo);
+    glBufferData(GL_ELEMENT_ARRAY_BUFFER, 0, nullptr, GL_DYNAMIC_DRAW);
+
+    // attributes
+    glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, sizeof(Vertex), reinterpret_cast<const void*>(offsetof(Vertex, m_position)));
+    glEnableVertexAttribArray(0);
+
+    glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, sizeof(Vertex), reinterpret_cast<const void*>(offsetof(Vertex, m_normal)));
+    glEnableVertexAttribArray(1);
+    
+    glVertexAttribPointer(2, 2, GL_FLOAT, GL_FALSE, sizeof(Vertex), reinterpret_cast<const void*>(offsetof(Vertex, m_texCoord)));
+    glEnableVertexAttribArray(2);
+
+    glBindBuffer(GL_ARRAY_BUFFER, 0);
+    glBindVertexArray(0);
+}
+
+void Mesh::Upload() const {
+    glBindVertexArray(m_vao);
+
+    glBindBuffer(GL_ARRAY_BUFFER, m_vbo);
+    glBufferData(GL_ARRAY_BUFFER, m_vertexBuffer.size() * sizeof(Vertex), m_vertexBuffer.data(), GL_DYNAMIC_DRAW);
+
+    // Upload indices
+    glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, m_ebo);
+    glBufferData(GL_ELEMENT_ARRAY_BUFFER, m_indexBuffer.size() * sizeof(unsigned int), m_indexBuffer.data(), GL_DYNAMIC_DRAW);
+
+    glBindVertexArray(0);
+}
+
+void Mesh::Render(unsigned int count)
+{
+    Bind();
+    if (count > 1) {
+        glDrawElementsInstanced(GL_TRIANGLES, static_cast<GLsizei>(m_indexBuffer.size()), GL_UNSIGNED_INT, 0, count);
+    } else {
+        glDrawElements(GL_TRIANGLES, static_cast<GLsizei>(m_indexBuffer.size()), GL_UNSIGNED_INT, 0);
+    }
+    Unbind();
+}