Package | flash.filters |
Class | public final class BlurFilter |
Inheritance | BlurFilter BitmapFilter Object |
Language Version: | ActionScript 3.0 |
Runtime Versions: | AIR 1.0 Flash Player 9 |
quality
property
of this filter is set to low, the result is a softly unfocused look.
When the quality
property is set to high, it approximates a Gaussian blur
filter. You can apply the filter to any display object (that is, objects that inherit
from the DisplayObject class),
such as MovieClip, SimpleButton, TextField, and Video objects, as well as to BitmapData objects.
To create a new filter, use the constructor new BlurFilter()
.
The use of filters depends on the object to which you apply the filter:
- To apply filters to movie clips, text fields, buttons, and video, use the
filters
property (inherited from DisplayObject). Setting thefilters
property of an object does not modify the object, and you can remove the filter by clearing thefilters
property. - To apply filters to BitmapData objects, use the
BitmapData.applyFilter()
method. CallingapplyFilter()
on a BitmapData object takes the source BitmapData object and the filter object and generates a filtered image as a result.
If you apply a filter to a display object, the cacheAsBitmap
property of the
display object is set to true
. If you remove all filters, the original value of
cacheAsBitmap
is restored.
This filter supports Stage scaling. However, it does not support general scaling,
rotation, and skewing. If the object itself is scaled (scaleX
and scaleY
are not set to 100%), the
filter effect is not scaled. It is scaled only when the user zooms in on the Stage.
A filter is not applied if the resulting image exceeds the maximum dimensions. In AIR 1.5 and Flash Player 10, the maximum is 8,191 pixels in width or height, and the total number of pixels cannot exceed 16,777,215 pixels. (So, if an image is 8,191 pixels wide, it can only be 2,048 pixels high.) In Flash Player 9 and earlier and AIR 1.1 and earlier, the limitation is 2,880 pixels in height and 2,880 pixels in width. If, for example, you zoom in on a large movie clip with a filter applied, the filter is turned off if the resulting image exceeds the maximum dimensions.
See also
flash.display.DisplayObject.cacheAsBitmap
flash.display.BitmapData.applyFilter()
Property | Defined By | ||
---|---|---|---|
blurX : Number
The amount of horizontal blur. | BlurFilter | ||
blurY : Number
The amount of vertical blur. | BlurFilter | ||
constructor : Object
A reference to the class object or constructor function for a given object instance. | Object | ||
prototype : Object [static]
A reference to the prototype object of a class or function object. | Object | ||
quality : int
The number of times to perform the blur. | BlurFilter |
Method | Defined By | ||
---|---|---|---|
Initializes the filter with the specified parameters. | BlurFilter | ||
[override]
Returns a copy of this filter object. | BlurFilter | ||
Indicates whether an object has a specified property defined. | Object | ||
Indicates whether an instance of the Object class is in the prototype chain of the object specified
as the parameter. | Object | ||
Indicates whether the specified property exists and is enumerable. | Object | ||
Sets the availability of a dynamic property for loop operations. | Object | ||
Returns the string representation of this object, formatted according to locale-specific conventions. | Object | ||
Returns the string representation of the specified object. | Object | ||
Returns the primitive value of the specified object. | Object |
blurX | property |
blurX:Number
Language Version: | ActionScript 3.0 |
Runtime Versions: | AIR 1.0 Flash Player 9 |
The amount of horizontal blur. Valid values are from 0 to 255 (floating point). The default value is 4. Values that are a power of 2 (such as 2, 4, 8, 16 and 32) are optimized to render more quickly than other values.
Implementation
public function get blurX():Number
public function set blurX(value:Number):void
blurY | property |
blurY:Number
Language Version: | ActionScript 3.0 |
Runtime Versions: | AIR 1.0 Flash Player 9 |
The amount of vertical blur. Valid values are from 0 to 255 (floating point). The default value is 4. Values that are a power of 2 (such as 2, 4, 8, 16 and 32) are optimized to render more quickly than other values.
Implementation
public function get blurY():Number
public function set blurY(value:Number):void
quality | property |
quality:int
Language Version: | ActionScript 3.0 |
Runtime Versions: | AIR 1.0 Flash Player 9 |
The number of times to perform the blur. The default value is BitmapFilterQuality.LOW
,
which is equivalent to applying the filter once. The value BitmapFilterQuality.MEDIUM
applies the filter twice; the value BitmapFilterQuality.HIGH
applies it three times
and approximates a Gaussian blur. Filters with lower values are rendered more quickly.
For most applications, a quality
value of low, medium, or high is sufficient.
Although you can use additional numeric values up to 15 to increase the number of times the blur
is applied,
higher values are rendered more slowly. Instead of increasing the value of quality
,
you can often get a similar effect, and with faster rendering, by simply increasing the values
of the blurX
and blurY
properties.
You can use the following BitmapFilterQuality constants to specify values of the
quality
property:
BitmapFilterQuality.LOW
BitmapFilterQuality.MEDIUM
BitmapFilterQuality.HIGH
Implementation
public function get quality():int
public function set quality(value:int):void
BlurFilter | () | Constructor |
public function BlurFilter(blurX:Number = 4.0, blurY:Number = 4.0, quality:int = 1)
Language Version: | ActionScript 3.0 |
Runtime Versions: | AIR 1.0 Flash Player 9 |
Initializes the filter with the specified parameters. The default values create a soft, unfocused image.
ParametersblurX:Number (default = 4.0 ) — The amount to blur horizontally. Valid values are from 0 to 255.0 (floating-point
value).
| |
blurY:Number (default = 4.0 ) — The amount to blur vertically. Valid values are from 0 to 255.0 (floating-point
value).
| |
quality:int (default = 1 ) — The number of times to apply the filter. You can specify the quality using
the BitmapFilterQuality constants:
High quality approximates a Gaussian blur. For most applications, these three values are sufficient. Although you can use additional numeric values up to 15 to achieve different effects, be aware that higher values are rendered more slowly. |
clone | () | method |
override public function clone():BitmapFilter
Language Version: | ActionScript 3.0 |
Runtime Versions: | AIR 1.0 Flash Player 9 |
Returns a copy of this filter object.
ReturnsBitmapFilter — A new BlurFilter instance with all the same
properties as the original BlurFilter instance.
|
- Import the required classes.
- Declare three properties used in the
draw()
function, which draws the object to which the blur filter is applied. - Create the
BlurFilterExample()
constructor function, which does the following:- Calls the
draw()
function, which is declared later. - Declares a
filter
variable as a BitmapFilter object and assigns it to the return of a call togetBitmapFilter()
. - Creates a new Array object
myFilters
and addsfilter
to the array, and assignsmyFilters
to thefilters
property of the BlurFilterExample object. This applies all filters found inmyFilters
, which in this case is onlyfilter
.
- Calls the
- Create the
getBitmapFilter()
function to create and set properties for the filter. - Create the
draw()
function. This function uses methods of the Graphics class, accessed through thegraphics
property of the Sprite class, to draw the square.
package { import flash.display.Sprite; import flash.filters.BitmapFilter; import flash.filters.BitmapFilterQuality; import flash.filters.BlurFilter; public class BlurFilterExample extends Sprite { private var bgColor:uint = 0xFFCC00; private var size:uint = 80; private var offset:uint = 50; public function BlurFilterExample() { draw(); var filter:BitmapFilter = getBitmapFilter(); var myFilters:Array = new Array(); myFilters.push(filter); filters = myFilters; } private function getBitmapFilter():BitmapFilter { var blurX:Number = 30; var blurY:Number = 30; return new BlurFilter(blurX, blurY, BitmapFilterQuality.HIGH); } private function draw():void { graphics.beginFill(bgColor); graphics.drawRect(offset, offset, size, size); graphics.endFill(); } } }
Fri Mar 19 2010, 02:45 AM -07:00