code: func RegionMake2D(x, y, width, height int) Region {
  	return Region{
  		Origin: Origin{x, y, 0},
  		Size:   Size{width, height, 1},
  	}
  }
docs: // RegionMake2D returns a 2D, rectangular region for image or texture data.
  //
  // Reference: https://developer.apple.com/documentation/metal/1515675-mtlregionmake2d.