The rectangle within the sprite to render. Note that the second x and y are actually the width and height of the Rect. The values are proportions of the width and height of the image in the Texture property.
Sprite providers due to the current Unity implementation at the time of writing this have issues with switching images very quickly. They will often flash white, causing a health hazard to photo sensitive users. Having all the sprites on UIX elements at once and switching their OrderOffset to change which element renders on top will remove the flashing and is currently the only way to combat this issue.
