Chapter 9. Masking Effects

Masking is one of those concepts with which people sometimes have a little trouble. However, after you get past the conceptual hurdle , masking is a great addition to your Flash skill set. So what is a mask? You'll hear masks referred to as "holes" or " windows ," but I think my favorite analogy is that a mask is like a stencil. You probably used stencils in your early school years to create posters and signs with neat, concise lettering. To do so, you lay the stencil on top of a piece of paper and paint in the holes. The stencil protects the underlying paper, except where the holes are. When you peel off the stencil, you can see nice, neat painted letters . That's pretty much what a mask does in Flash ”it screens off the underlying layer so that you see only the part where the holes are.

In this chapter, you learn how to do the following:

• Create various types of masking effects. Masking can be used in many ways. You can use it to create interesting motion and text effects. You also can use it to quickly and easily apply static effects to objects on the Stage.

• Soften mask edges. Masks in Flash don't work with gradients, but you can use a little trickery to give your masked effect a nice, soft edge.

• Use ActionScript to control a masked movie. You can't use ActionScript to control a mask, but you can control the movie being masked. You also can control a movie clip that has internal masking.

Just in case masking is new to you, and even if it isn't, it's a good idea to review the basics of masking so that you know what works and what doesn't.