feat(VBOs): rework vbo functions and add comments

inc/core/vbo.hpp

@@ -5,19 +5,29 @@
 
 #include "glad/glad.h"
 
+// A VBO (Vertex Buffer Object) is a contiguous block of GPU memory that stores
+// vertex data as raw bytes.
 class VBO
 {
  private:
-  unsigned int id;
+  GLuint id;  // OpenGL handle for this buffer
 
  public:
-  VBO();
+  // VBO constructor
+  // It uploads raw vertex data into GPU memory (VRAM).
+  // The interpretation of this data is defined later by the VAO.
+  VBO(const void *data, size_t size);
+
+  // VBO destructor
+  // Deletes the GPU buffer when the VBO object goes out of scope. Frees the
+  // VRAM associated with this VBO.
   ~VBO();
 
-  void setData(const GLfloat* vertices, size_t size);
-
+  // Binds this VBO to the current GL_ARRAY_BUFFER target
   void bind();
-  void unbind();
+
+  // unbinds current GL_ARRAY_BUFFER target (it's replaced by null id)
+  static void unbind();
 };
 
 #endif