oil-backend-opengl.c

    /* create and populate a VBO and VAO */
    glGenBuffers(1, &vbo);
    glGenVertexArrays(1, &vao);
    
    glBindVertexArray(vao);
    glBindBuffer(GL_ARRAY_BUFFER, vbo);
    
    glBufferData(GL_ARRAY_BUFFER, sizeof(OILVertex) * vertices_length, vertices, GL_STATIC_DRAW);
    glVertexPointer(3, GL_FLOAT, sizeof(OILVertex), (void *)offsetof(OILVertex, x));
    glTexCoordPointer(2, GL_FLOAT, sizeof(OILVertex), (void *)offsetof(OILVertex, s));
    glColorPointer(4, GL_UNSIGNED_BYTE, sizeof(OILVertex), (void *)offsetof(OILVertex, color));
    
    /* draw */
    glDrawElements(GL_TRIANGLES, indices_length, GL_UNSIGNED_INT, indices);
    
    /* free our VBO and VAO */
    glDeleteVertexArrays(1, &vao);
    glDeleteBuffers(1, &vbo);