ACTIONSCRIPT 3 Developer’s Guide en

ACTIONSCRIPT 3.0 DEVELOPER’S GUIDE
Filtering display objects
Creating and applying filters
Flash Player 9 and later, Adobe AIR 1.0 and later
Filters allow you to apply a range of effects to bitmap and display objects, ranging from drop shadows to bevels and
blurs. Each filter is defined as a class, so applying filters involves creating instances of filter objects, which is no different
from constructing any other object. Once you’ve created an instance of a filter object, it can easily be applied to a
display object by using the object’s filters property, or in the case of a BitmapData object, by using the
applyFilter() method.
Creating a filter
Flash Player 9 and later, Adobe AIR 1.0 and later
To create a filter object, simply call the constructor method of your selected filter class. For example, to create a
DropShadowFilter object, use the following code:
import flash.filters.DropShadowFilter;
var myFilter:DropShadowFilter = new DropShadowFilter();
Although not shown here, the DropShadowFilter() constructor (like all the filter classes’ constructors) accepts
several optional parameters that can be used to customize the appearance of the filter effect.
Applying a filter
Flash Player 9 and later, Adobe AIR 1.0 and later
Once you've constructed a filter object, you can apply it to a display object or a BitmapData object; how you apply the
filter depends on the object to which you’re applying it.
Applying a filter to a display object
When you apply filter effects to a display object, you apply them through the filters property. The filters
property of a display object is an Array instance, whose elements are the filter objects applied to the display object. To
apply a single filter to a display object, create the filter instance, add it to an Array instance, and assign that Array object
to the display object’s filters property:
Last updated 6/6/2012
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