Actionscript mask

programming flash
1

Hello people,

I have created a mask using actionscript, but I found that it will only mask over graphic/movieclip/etc… am I doing something wrong here?


this.createEmptyMovieClip("mask_mc", this.getNextHighestDepth());
mask_mc.beginFill(0xFF0000);
mask_mc.moveTo(0, 0);
mask_mc.lineTo(550, 0);
mask_mc.lineTo(550, 400);
mask_mc.lineTo(0, 400);
mask_mc.lineTo(0, 0);
mask_mc.endFill();
//
bg_mc.setMask(mask_mc);
a_mc.setMask(mask_mc);

This will only mask “a_mc” movieclip.