code: func (m *Monitor) BitDepth() (red, green, blue int) {
  	var mode *glfw.VidMode
  	mainthread.Call(func() {
  		mode = m.monitor.GetVideoMode()
  	})
  	red = mode.RedBits
  	green = mode.GreenBits
  	blue = mode.BlueBits
  	return
  }
docs: // BitDepth returns the number of bits per color of the Monitor.