Masking is a very useful
technique in Flash. By applying a mask on a movie clip,
you can restrict the visible area of the target clip
to the mask area. Below is a simple example (press the
buttons to show the target movie, the mask clip and
the masking effect):
To apply a mask is very easy in the Flash
Open a new file in Flash editor. Draw
whatever you like as the target clip on the main stage.
Insert a new layer above the orginal layer.
Draw your mask shape there. Right click on the new layer
and select "mask" in the pop up menu. The
timeline will look like:
The means the mask has been applied to
the target clip.
Alternative way: Using Actionscript
In actionscript, you can use the "setMask"
function to apply a mask (clip) on a target clip. e.g.
where target_clip is the target clip and
the mask_clip is the mask clip.
Thats all. Simple? Want some more fancy
effect? Look at our tutorial on Moving
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