BlurFilter  - AS3

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.

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.

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

Initializes the filter with the specified parameters. The default values create a soft, unfocused image.

Returns a copy of this filter object.

1. Import the required classes.
2. Declare three properties used in the draw() function, which draws the object to which the blur filter is applied.
3. 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 to getBitmapFilter().
   • Creates a new Array object myFilters and adds filter to the array, and assigns myFilters to the filters property of the BlurFilterExample object. This applies all filters found in myFilters, which in this case is only filter.
4. Create the getBitmapFilter() function to create and set properties for the filter.
5. Create the draw() function. This function uses methods of the Graphics class, accessed through the graphics 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();
        }
    }
}