code: func Init() {
  	err := gl.Init()
  	if err != nil {
  		panic(err)
  	}
  	gl.Enable(gl.BLEND)
  	gl.Enable(gl.SCISSOR_TEST)
  	gl.BlendEquation(gl.FUNC_ADD)
  }
docs: // Init initializes OpenGL by loading function pointers from the active OpenGL context.
  // This function must be manually run inside the main thread (using "github.com/faiface/mainthread"
  // package).
  //
  // It must be called under the presence of an active OpenGL context, e.g., always after calling
  // window.MakeContextCurrent(). Also, always call this function when switching contexts.