In animated motion films, is the voice casting done before or after computer graphics animations?
Normally it is done before the animation.
The voice acting is done and then the animators will match the animation of the characters to the voice.
They will sometimes use the movement of the actors too. In Aladdin a lot of the genies movements and behaviours can be seen in footage of Robin Williams delivering the lines.
It also allows the actors to ad-lib lines that are the put into the movie.
You can see some of what I mentioned here although I’m sure there are better videos...