GlowFilter  - AS3

The alpha transparency value for the color. Valid values are 0 to 1. For example, .25 sets a transparency value of 25%. The default value is 1.

The amount of horizontal blur. Valid values are 0 to 255 (floating point). The default value is 6. 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 0 to 255 (floating point). The default value is 6. 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 color of the glow. Valid values are in the hexadecimal format 0xRRGGBB. The default value is 0xFF0000.

Specifies whether the glow is an inner glow. The value true indicates an inner glow. The default is false, an outer glow (a glow around the outer edges of the object).

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

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.

Related API Elements

The strength of the imprint or spread. The higher the value, the more color is imprinted and the stronger the contrast between the glow and the background. Valid values are 0 to 255. The default is 2.

Initializes a new GlowFilter instance with the specified parameters.

Related API Elements

Returns a copy of this filter object.

1. Import the required classes.
2. Declare three properties used in the draw method, which uses methods of the Graphics class accessed through the graphics property of Sprite to draw an orange square.
3. Create the constructor function, which does the following:
   • Calls the draw function to create a rectangle.
   • Creates a BitmapFilter object glowFilter and assigns it the return values from the getBitmapFilter() function.
   • Assigns the array of values from the glowFilter object to the filters property of the root display object. In this case, all display object children of the root display object inherit the glow filter properties. So, the rectangle created in the the draw() function displays the glow filter properties.

package {
    import flash.display.Sprite;
    import flash.events.Event;
    import flash.events.MouseEvent;
    import flash.filters.BitmapFilter;
    import flash.filters.BitmapFilterQuality;
    import flash.filters.GlowFilter;

    public class GlowFilterExample extends Sprite {
        private var bgColor:uint = 0xFFCC00;
        private var size:uint    = 80;
        private var offset:uint  = 50;

        public function GlowFilterExample() {
        //draw the rectangle using the draw() function below
            draw();
            
        //assign the values from getBitmapFilter function below
        //to a BitmapFilter object "glowFilter"
            var glowFilter:BitmapFilter = getBitmapFilter();
            
        //populate the filters property of the root display object with the array of values
        //from the glowFilter object.
            filters = [ glowFilter ];
        }

        private function getBitmapFilter():BitmapFilter {
            var color:Number = 0x33CCFF;
            var alpha:Number = 0.8;
            var blurX:Number = 35;
            var blurY:Number = 35;
            var strength:Number = 2;
            var inner:Boolean = false;
            var knockout:Boolean = false;
            var quality:Number = BitmapFilterQuality.HIGH;

            return new GlowFilter(color,
                                  alpha,
                                  blurX,
                                  blurY,
                                  strength,
                                  quality,
                                  inner,
                                  knockout);
        }

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