I doing an assignment in school that requires me to use solid
black shapes to create a compostion. (Ah yes! One of those things. )
So we are allowed to overlap two, black shapes and invert the
overlaped sections to create a new, white shape. So my question is
how to do this. I would really like to make the inverting of the
shapes dynamic. Meaning that I would rather not have to cut up the
shape themselves. That way I can move the shapes around still to try
different ideas.

Thank you,