[flexcoders] Inverting a Shape

[Sebastian Mohr]

Hi there,

I want to create a mask which prevents a component
from being shown, but the following code is doing the
exact opposite:

var surroundingMask:Shape = new Shape();
surroundingMask.blendMode = BlendMode.INVERT;

surroundingMask.graphics.beginFill(0x00FFFF, 0.5);
surroundingMask.graphics.drawRoundRect(x, y, width, height, 0);
surroundingMask.graphics.endFill();

I thought that the BlendMode.INVERT is going to help
but it doesn't.

Any ideas?
masu