0,0 should be None (native size, centered)
1,0 should be Fill (stretched on both width and height to fill rectangle)
2,0 should be Uniform (stretched to fill, fit and keep ratio)
3,0 should be UniformToFill (stretched to fill, keep ratio, but not to fit)

0,1 should be empty (no image, not even the rectangle border)
1,1 should be empty (no image, not even the rectangle border)
2,1 should be None like 0,0
3,1 should be UniformToFill like 0,3