Creating a Mask
Masks are like stencils: They reveal parts of images that are below. Use them to reveal portions of layers in your movies. For example, you can use text as a mask to reveal parts of an image within the shapes of the letters, as shown in Figure 3.28. Creating a mask is easy. Draw simple shapes on a separate layer that is above the layers you want to mask. Contrary to expectations, masks in Flash reveal rather than hide. So, remember to draw your mask in the shapes you want to reveal contents below them. When your mask shape is in place, Ctrl+click or right-click the layer and then select Mask from the context menu. This applies the mask and locks the mask layer and any layers below it that are masked.
→ For more details on using masks, see "Working with Dynamic Masks," page 362 (Chapter 17, "Unlocking the Power of Movie Clips").
Figure 3.28 Text can be used as a mask.