after effects mask question

[belovedmonster]

is there a way to change the shape of my masks for example...

say im doing a shot where i want two of the same person on screen at the same time. There no need for blue screen just need to create a mask round one so i can put it on the other side of the shot with the other guy... the only problem is that i need the mask to change its position/shape half way through the sequence to accomodate what is happening on screen...

how do i change the shape/position of masks. Basicly in the same way you would use key frames and toggle the parameters of an effect to match the movie.

[MatJimMood]

you edit a mask in the same way that you edit an effect

all you have to do after you've created the mask is go to the animation menu and click on 'add mask shape key frame'

from then on simply move forwards in the time control and edit the mask as needed

the new keyframes are created automatically