Values
Pad
The image is not transformed
Stretch
The image is scaled to fit
Cover
The image is scaled uniformly to fill, cropping if necessary
Contain
The image is scaled uniformly to fit without cropping
Tile
The image is duplicated horizontally and vertically
TileVertically
The image is stretched horizontally and tiled vertically
TileHorizontally
The image is stretched vertically and tiled horizontally