Adobe® Flex® 4 Language Reference
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flash.filters 
GradientBevelFilter 
Packageflash.filters
Classpublic final class GradientBevelFilter
InheritanceGradientBevelFilter Inheritance BitmapFilter Inheritance Object

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9

The GradientBevelFilter class lets you apply a gradient bevel effect to display objects. A gradient bevel is a beveled edge, enhanced with gradient color, on the outside, inside, or top of an object. Beveled edges make objects look three-dimensional. 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.

The use of filters depends on the object to which you apply the filter:

  • To apply filters to display objects, use the filters property. Setting the filters property of an object does not modify the object, and you can remove the filter by clearing the filters property.
  • To apply filters to BitmapData objects, use the BitmapData.applyFilter() method. Calling applyFilter() 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 clear 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 (if scaleX and scaleY are set to a value other than 1.0), 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. For example, if 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.

View the examples

See also



Public Properties
 PropertyDefined By
  alphas : Array
An array of alpha transparency values for the corresponding colors in the colors array.
GradientBevelFilter
  angle : Number
The angle, in degrees.
GradientBevelFilter
  blurX : Number
The amount of horizontal blur.
GradientBevelFilter
  blurY : Number
The amount of vertical blur.
GradientBevelFilter
  colors : Array
An array of RGB hexadecimal color values to use in the gradient.
GradientBevelFilter
 Inheritedconstructor : Object
A reference to the class object or constructor function for a given object instance.
Object
  distance : Number
The offset distance.
GradientBevelFilter
  knockout : Boolean
Specifies whether the object has a knockout effect.
GradientBevelFilter
 Inheritedprototype : Object
[static] A reference to the prototype object of a class or function object.
Object
  quality : int
The number of times to apply the filter.
GradientBevelFilter
  ratios : Array
An array of color distribution ratios for the corresponding colors in the colors array.
GradientBevelFilter
  strength : Number
The strength of the imprint or spread.
GradientBevelFilter
  type : String
The placement of the bevel effect.
GradientBevelFilter
Public Methods
 MethodDefined By
  
GradientBevelFilter(distance:Number = 4.0, angle:Number = 45, colors:Array = null, alphas:Array = null, ratios:Array = null, blurX:Number = 4.0, blurY:Number = 4.0, strength:Number = 1, quality:int = 1, type:String = "inner", knockout:Boolean = false)
Initializes the filter with the specified parameters.
GradientBevelFilter
  
[override] Returns a copy of this filter object.
GradientBevelFilter
 Inherited
Indicates whether an object has a specified property defined.
Object
 Inherited
Indicates whether an instance of the Object class is in the prototype chain of the object specified as the parameter.
Object
 Inherited
Indicates whether the specified property exists and is enumerable.
Object
 Inherited
Sets the availability of a dynamic property for loop operations.
Object
 Inherited
Returns the string representation of this object, formatted according to locale-specific conventions.
Object
 Inherited
Returns the string representation of the specified object.
Object
 Inherited
Returns the primitive value of the specified object.
Object
Property Detail

alphas

property
alphas:Array

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9

An array of alpha transparency values for the corresponding colors in the colors array. Valid values for each element in the array are 0 to 1. For example, .25 sets a transparency value of 25%.

The alphas property cannot be changed by directly modifying its values. Instead, you must get a reference to alphas, make the change to the reference, and then set alphas to the reference.

The colors, alphas, and ratios properties are related. The first element in the colors array corresponds to the first element in the alphas array and in the ratios array, and so on.



Implementation
    public function get alphas():Array
    public function set alphas(value:Array):void

Throws
TypeError — The Array is null when being set

See also

angle

property 
angle:Number

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9

The angle, in degrees. Valid values are 0 to 360. The default is 45.

The angle value represents the angle of the theoretical light source falling on the object. The value determines the angle at which the gradient colors are applied to the object: where the highlight and the shadow appear, or where the first color in the array appears. The colors are then applied in the order in which they appear in the array.



Implementation
    public function get angle():Number
    public function set angle(value:Number):void

See also

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 0 to 255. A blur of 1 or less means that the original image is copied as is. 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 0 to 255. A blur of 1 or less means that the original image is copied as is. 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

colors

property 
colors:Array

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9

An array of RGB hexadecimal color values to use in the gradient. For example, red is 0xFF0000, blue is 0x0000FF, and so on.

The colors property cannot be changed by directly modifying its values. Instead, you must get a reference to colors, make the change to the reference, and then set colors to the reference.

The colors, alphas, and ratios properties are related. The first element in the colors array corresponds to the first element in the alphas array and in the ratios array, and so on.



Implementation
    public function get colors():Array
    public function set colors(value:Array):void

Throws
TypeError — The Array is null when being set

See also

distance

property 
distance:Number

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9

The offset distance. Valid values are 0 to 8. The default value is 4.0.



Implementation
    public function get distance():Number
    public function set distance(value:Number):void

knockout

property 
knockout:Boolean

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9

Specifies whether the object has a knockout effect. A knockout effect makes the object's fill transparent and reveals the background color of the document. The value true specifies a knockout effect; the default is false (no knockout effect).



Implementation
    public function get knockout():Boolean
    public function set knockout(value:Boolean):void

quality

property 
quality:int

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9

The number of times to apply the filter. 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. 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 achieve different effects, 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.



Implementation
    public function get quality():int
    public function set quality(value:int):void

See also

ratios

property 
ratios:Array

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9

An array of color distribution ratios for the corresponding colors in the colors array. Valid values for each element in the array are 0 to 255.

The ratios property cannot be changed by directly modifying its values. Instead, you must get a reference to ratios, make the change to the reference, and then set ratios to the reference.

The colors, alphas, and ratios properties are related. The first element in the colors array corresponds to the first element in the alphas array and in the ratios array, and so on.

To understand how the colors in a gradient bevel are distributed, think first of the colors that you want in your gradient bevel. Consider that a simple bevel has a highlight color and shadow color; a gradient bevel has a highlight gradient and a shadow gradient. Assume that the highlight appears on the top-left corner, and the shadow appears on the bottom-right corner. Assume that one possible usage of the filter has four colors in the highlight and four in the shadow. In addition to the highlight and shadow, the filter uses a base fill color that appears where the edges of the highlight and shadow meet. Therefore the total number of colors is nine, and the corresponding number of elements in the ratios array is nine.

If you think of a gradient as composed of stripes of various colors, blending into each other, each ratio value sets the position of the color on the radius of the gradient, where 0 represents the outermost point of the gradient and 255 represents the innermost point of the gradient. For a typical usage, the middle value is 128, and that is the base fill value. To get the bevel effect shown in the image below, assign the ratio values as follows, using the example of nine colors:

  • The first four colors range from 0-127, increasing in value so that each value is greater than or equal to the previous one. This is the highlight bevel edge.
  • The fifth color (the middle color) is the base fill, set to 128. The pixel value of 128 sets the base fill, which appears either outside the shape (and around the bevel edges) if the type is set to outer; or inside the shape, effectively covering the object's own fill, if the type is set to inner.
  • The last four colors range from 129-255, increasing in value so that each value is greater than or equal to the previous one. This is the shadow bevel edge.

If you want an equal distribution of colors for each edge, use an odd number of colors, where the middle color is the base fill. Distribute the values between 0-127 and 129-255 equally among your colors, then adjust the value to change the width of each stripe of color in the gradient. For a gradient bevel with nine colors, a possible array is [16, 32, 64, 96, 128, 160, 192, 224, 235]. The following image depicts the gradient bevel as described:

A nine color gradient bevel.

Keep in mind that the spread of the colors in the gradient varies based on the values of the blurX, blurY, strength, and quality properties, as well as the ratios values.



Implementation
    public function get ratios():Array
    public function set ratios(value:Array):void

Throws
TypeError — The Array is null when being set

See also

strength

property 
strength:Number

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9

The strength of the imprint or spread. The higher the value, the more color is imprinted and the stronger the contrast between the bevel and the background. Valid values are 0 to 255. A value of 0 means that the filter is not applied. The default value is 1.



Implementation
    public function get strength():Number
    public function set strength(value:Number):void

See also

type

property 
type:String

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9

The placement of the bevel effect. Possible values are BitmapFilterType constants:

  • BitmapFilterType.OUTER — Bevel on the outer edge of the object
  • BitmapFilterType.INNER — Bevel on the inner edge of the object
  • BitmapFilterType.FULL — Bevel on top of the object



Implementation
    public function get type():String
    public function set type(value:String):void
Constructor Detail

GradientBevelFilter

()Constructor
public function GradientBevelFilter(distance:Number = 4.0, angle:Number = 45, colors:Array = null, alphas:Array = null, ratios:Array = null, blurX:Number = 4.0, blurY:Number = 4.0, strength:Number = 1, quality:int = 1, type:String = "inner", knockout:Boolean = false)

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0 Flash Player 9

Initializes the filter with the specified parameters.

Parameters
distance:Number (default = 4.0) — The offset distance. Valid values are 0 to 8.
 
angle:Number (default = 45) — The angle, in degrees. Valid values are 0 to 360.
 
colors:Array (default = null) — An array of RGB hexadecimal color values to use in the gradient. For example, red is 0xFF0000, blue is 0x0000FF, and so on.
 
alphas:Array (default = null) — An array of alpha transparency values for the corresponding colors in the colors array. Valid values for each element in the array are 0 to 1. For example, .25 sets a transparency value of 25%.
 
ratios:Array (default = null) — An array of color distribution ratios; valid values are 0 to 255.
 
blurX:Number (default = 4.0) — The amount of horizontal blur. Valid values are 0 to 255. A blur of 1 or less means that the original image is copied as is. 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.
 
blurY:Number (default = 4.0) — The amount of vertical blur. Valid values are 0 to 255. A blur of 1 or less means that the original image is copied as is. Values that are a power of 2 (such as 2, 4, 8, 16 and 32) are optimized to render more quickly than other values.
 
strength:Number (default = 1) — The strength of the imprint or spread. The higher the value, the more color is imprinted and the stronger the contrast between the bevel and the background. Valid values are 0 to 255. A value of 0 means that the filter is not applied.
 
quality:int (default = 1) — The quality of the filter. Use BitmapFilterQuality constants:
  • BitmapFilterQuality.LOW
  • BitmapFilterQuality.MEDIUM
  • BitmapFilterQuality.HIGH

For more information, see the description of the quality property.

 
type:String (default = "inner") — The placement of the bevel effect. Possible values are BitmapFilterType constants:
  • BitmapFilterType.OUTER — Bevel on the outer edge of the object
  • BitmapFilterType.INNER — Bevel on the inner edge of the object
  • BitmapFilterType.FULL — Bevel on top of the object
 
knockout:Boolean (default = false) — Specifies whether a knockout effect is applied. The value true makes the object's fill transparent and reveals the background color of the document.

See also

Method Detail

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.

Returns
BitmapFilter — A new GradientBevelFilter instance with all the same properties as the original GradientBevelFilter instance.
GradientBevelFilterExample.as

The following example draws a square and applies a gradient bevel filter to it. The general workflow of this example is as follows:
  1. Import the required classes.
  2. Declare global variables to define the square and the filter.
  3. Create the constructor functions, which does the following:
    • Calls the draw() method, which uses methods of the Graphics class accessed through the graphics property of Sprite to draw a gray square.
    • Creates a BitmapFilter object named filter and assigns it the return value of a call to getBitmapFilter(), which creates the filter.
    • Creates a new array named myFilters and adds filter to it.
    • Assigns myFilters to the filters property of the GradientBevelFilterExample object. This applies all filters found in myFilters, which in this case is only filter.

package {
    import flash.display.Sprite;
    import flash.filters.BitmapFilter;
    import flash.filters.BitmapFilterQuality;
    import flash.filters.BitmapFilterType;
    import flash.filters.GradientBevelFilter;

    public class GradientBevelFilterExample extends Sprite {
        private var bgColor:uint     = 0xCCCCCC;
        private var size:uint        = 80;
        private var offset:uint      = 50;
        private var distance:Number  = 5;
        private var angleInDegrees:Number = 225; // opposite 45 degrees
        private var colors:Array     = [0xFFFFFF, 0xCCCCCC, 0x000000];
        private var alphas:Array     = [1, 0, 1];
        private var ratios:Array     = [0, 128, 255];
        private var blurX:Number     = 8;
        private var blurY:Number     = 8;
        private var strength:Number  = 2;
        private var quality:Number   = BitmapFilterQuality.HIGH
        private var type:String      = BitmapFilterType.INNER;
        private var knockout:Boolean = true;

        public function GradientBevelFilterExample() {
            draw();
            var filter:BitmapFilter = getBitmapFilter();
            var myFilters:Array = new Array();
            myFilters.push(filter);
            filters = myFilters;
        }

        private function getBitmapFilter():BitmapFilter {
            return new GradientBevelFilter(distance,
                                           angleInDegrees,
                                           colors,
                                           alphas,
                                           ratios,
                                           blurX,
                                           blurY,
                                           strength,
                                           quality,
                                           type,
                                           knockout);
        }

        private function draw():void {
            graphics.beginFill(bgColor);
            graphics.drawRect(offset, offset, size, size);
            graphics.endFill();
        }
    }
}