Is there a way to tell a sprite to draw a dynamically selected subregion of itself, e.g. for revealing a sprite in a top-down manner?
For example, suppose that I have a 64x64 sprite, and in frame n, I want to draw a 64xn subregion of the sprite, with both vertex positions and UVs forming a rectange from (0, 0) to (64, n) , so that the sprite reveals from the top down? This obviously can't be done with just a scale because I want the same screen pixel of the sprite to always correspond to the same texel.
Is there an easy way to do this in NGUI?
Thanks,
Alex
