SimpleEngine/include/simpleengine/gfx/vao.h

69 lines
2.2 KiB
C++

#pragma once
#ifdef __linux__
#include <GL/glew.h>
#include <GL/gl.h>
#elif
#include <gl/glew.h>
#include <gl/gl.h>
#endif
#include "vbo.h"
namespace simpleengine::gfx {
class VAO {
public:
GLuint handle;
VAO() {
glCreateVertexArrays(1, &handle);
}
~VAO() {
destroy();
}
void destroy() {
glDeleteVertexArrays(1, &handle);
}
void bind() const {
glBindVertexArray(handle);
}
// TODO: Fix this.
void enable_attrib(const VBO& vbo, GLuint index, GLint size, GLenum type, GLsizei stride, size_t offset) const {
bind();
vbo.bind();
// NOTE: glVertexAttribPointer will AUTO-CONVERT integer values to floating point.
// Integer vertex attributes must be specified with glVertexAttribIPointer.
// THIS IS EVIL. OpenGL is bad. Who designed this to fail silently?
switch (type) {
case GL_BYTE:
case GL_UNSIGNED_BYTE:
case GL_SHORT:
case GL_UNSIGNED_SHORT:
case GL_INT:
case GL_UNSIGNED_INT:
case GL_INT_2_10_10_10_REV:
case GL_UNSIGNED_INT_2_10_10_10_REV:
glVertexAttribIPointer(index, size, type, stride, (void *) offset);
break;
default:
glVertexAttribPointer(index, size, type, GL_FALSE, stride, (void *) offset);
break;
}
glEnableVertexAttribArray(index);
// note that this is allowed, the call to glVertexAttribPointer registered VBO as the vertex attribute's
// bound vertex buffer object so afterwards we can safely unbind.
glBindBuffer(GL_ARRAY_BUFFER, 0);
// You can unbind the VAO afterwards so other VAO calls won't accidentally modify this VAO, but this
// rarely happens. Modifying other VAOs requires a call to glBindVertexArray anyways so we generally
// don't unbind VAOs (nor VBOs) when it's not directly necessary.
glBindVertexArray(0);
}
};
}