A question about masking capabilities

Hello! :slight_smile:

I’m a new Flash CS4 user, and am having tons of fun exploring all its incredible features! I’ve been busy building a website for my boss, and have run into an apparent limitation in the software. I would like to have a column of translucent, rotating rectangles; as they overlap, the shared regions change color. I had hoped to accomplish this with masks (that is, having a block of color that is only visible when and where two rectangles intersect), but I don’t think there is a way to have a mask depend on the motion of two symbols - or is there? Alternatively, I have experimented with Actionscript and the intersection method of the flash.geom.Rectangle class, but have had no luck with that either.

If someone could point me in the right direction - or let me know if this is even possible -I would very much appreciate it. Thanks in advance for your help!