If you did water pouring straight down, you could make a water vector graphic like it was falling...mask it from top to bottom, so the top starts appearing, then in the glass, mask a layer once it hits the bottom and make a water layer go up...to fill...I dont know what kind of idea you have, so I can't help you much more than that...do you know any bit on masking?...if not I can give you a link to some good sites. ----------------------------------------
The Learning process is just a way to get rid of all the stupids in your head.
Now where's that cute little kitten? :-X