package {

	import flash.display.Bitmap;
	import flash.display.BitmapData;
	import flash.display.BitmapDataChannel;
	import flash.display.BlendMode;
	import flash.filters.BevelFilter;
	import flash.filters.BitmapFilterQuality;
	import flash.filters.DisplacementMapFilter;
	import flash.filters.DropShadowFilter;
	import flash.geom.ColorTransform;
	import flash.geom.Matrix;
	import flash.geom.Point;
	import flash.text.TextField;
	import flash.text.TextFieldAutoSize;
	import flash.text.TextFormat;
	import flash.text.TextFormatAlign;

	[SWF(width=640, height=480, backgroundColor=0x202020)]

	/**
	* Demonstrates how DisplacementMapFilter can be used to distort a texture so that it appears to wrap around
	* a textfield. The map used for the displacement is generated by applying bevel filters to the field and
	* capturing this bitmap data.
	*/
	public class graphic_flex_image_effects_04_Flex_GlassEffect extends graphic_flex_image_effects_04_Flex_AbstractImageLoader {

		/**
		* Constructor. Passes path of image to load to super class.
		*/
		public function graphic_flex_image_effects_04_Flex_GlassEffect() {
			super("graphic-flex-image-effects-04-assets-glassBackground.jpg");
		}

		/**
		* Run after the image loads in super class. This creates a new transparent bitmap data and copies over pixels
		* under a certain brightness into it. Then two filters applied to produce a pooling paint effect.
		*/
		override protected function runPostImageLoad():void {
			var width:Number = stage.stageWidth;
			var height:Number = stage.stageHeight;
			// this will be used as the displacement map
			var map:BitmapData = new BitmapData(width, height, true, 0x00000000);
			// this will be used for the distorted texture
			var texturedText:BitmapData = map.clone();
			// creates a filtered textfield
			var textfield:TextField = createTextField(0x808080, 0xFFFFFF);
			// a matrix to translate the captured text bitmap data to be centered within the texture bitmap
			var matrix:Matrix = new Matrix();
			matrix.translate((width-textfield.width)/2, (height-textfield.height)/2);
			// draws the textfield, centered, within bitmap data the same dimensions as the texture bitmap
			map.draw(textfield, matrix);
			var displacementMapFilter:DisplacementMapFilter = new DisplacementMapFilter(
				map, new Point(), BitmapDataChannel.RED, BitmapDataChannel.RED, 15, 15
			);
			var bitmapData:BitmapData = _loadedBitmap.bitmapData;
			// displace the texture bitmap using the captured filtered textfield
			texturedText.applyFilter(bitmapData, texturedText.rect, new Point(), displacementMapFilter);
			var alphaChannel:uint = BitmapDataChannel.ALPHA;
			// use the alpha from textfield on the distorted texture
			texturedText.copyChannel(map, map.rect, new Point(), alphaChannel, alphaChannel);
			// reuse map bitmap data just because it is the same size
			map.draw(textfield, matrix);
			// color transform used to draw overlay lighting text onto textured text
			texturedText.draw(map, null, new ColorTransform(1, 1, 1, 0.6), BlendMode.OVERLAY);
			// additional filters applied to create glass-like lighting
			texturedText.applyFilter(texturedText, texturedText.rect, new Point(), new DropShadowFilter(1, 45, 0xFFFFFF, 0.8, 2, 2, 2, 1, true));
			texturedText.applyFilter(texturedText, texturedText.rect, new Point(), new DropShadowFilter(2, 45, 0, 0.5, 3, 3));
			// background slightly lightened
			bitmapData.colorTransform(bitmapData.rect, new ColorTransform(1, 1, 1, 1, 10, 10, 10));
			addChild(_loadedBitmap);
			addChild(new Bitmap(texturedText));
		}

		/**
		* Creates a textfield and applies a bevel filter using the specified highlight color.
		*
		* @param textColor The color to give the text.
		* @param highlightColor The color to give the bevel filter highlight.
		*
		* @return The textfield that was created.
		*/
		private function createTextField(textColor:uint, highlightColor:uint):TextField {
			var textfield:TextField = new TextField();
			textfield.autoSize = TextFieldAutoSize.LEFT;
			textfield.multiline = true;
			// change font face if Impact is not installed
			var textFormat:TextFormat = new TextFormat("Impact", 130, textColor);
			textFormat.align = TextFormatAlign.CENTER;
			textfield.defaultTextFormat = textFormat;
			textfield.text = "GLASS\nDISTORTION";
			var bevelFilter:BevelFilter = new BevelFilter(5, 45);
			bevelFilter.highlightColor = highlightColor;
			bevelFilter.blurX = bevelFilter.blurY = 7;
			textfield.filters = [bevelFilter];
			return textfield;
		}

	}

}