/** @language english
 * The DropShadowFilter class lets you add a drop shadow to display objects. The shadow algorithm is based on the same box filter that the blur filter uses. You have several options for the style of the drop shadow, including inner or outer shadow and knockout mode. You can apply the filter to any display object (that is, objects that inherit from the DisplayObject class).
 * @class LDropShadowFilter
 * @extends LObject
 * @constructor
 * @param {int} distance The offset distance for the shadow, in pixels.
 * @param {int} angle The angle of the shadow.
 * @param {int} color The color of the shadow.
 * @param {int} blur The amount of blur.
 * @example
 * 	var bitmapdata = new LBitmapData(event.target);  
 * 	var bitmap = new LBitmap(bitmapdata);
 * 	addChild(bitmap);
 * 	var shadow = new LDropShadowFilter(5,45,"#000000");
 * 	bitmap.filters = [shadow];
 * @examplelink <p><a href="../../../api/LDropShadowFilter/index.html" target="_blank">Try it »</a></p>
 * @since 1.6.0
 * @public
 */
var LDropShadowFilter = (function () {
	function LDropShadowFilter (distance, angle, color, blur) {
		var s = this;
		LExtends(s, LObject, []);
		s.type = "LDropShadowFilter";
		s.distance = distance ? distance : 0;
		s.angle = angle ? angle : 0;
		s.shadowColor = color ? color : "#000000";
		s.shadowBlur = blur ? blur : 20;
		s.setShadowOffset();
	}
	var p = {
		setShadowOffset : function () {
			var s = this;
			var a = s.angle * Math.PI / 180;
			s.shadowOffsetX = s.distance * Math.cos(a);
			s.shadowOffsetY = s.distance * Math.sin(a);
		},
		ll_show : function () {
			var s = this, c = LGlobal.canvas;
			c.shadowColor = s.shadowColor;
			c.shadowBlur = s.shadowBlur;
			c.shadowOffsetX = s.shadowOffsetX;
			c.shadowOffsetY = s.shadowOffsetY;
		},
		/** @language english
		 * Set the offset distance for the shadow.
		 * @method setDistance
		 * @param {int} distance the offset distance for the shadow.
		 * @since 1.6.0
		 * @public
		 */
		setDistance : function (distance) {
			this.distance = distance;
			this.setShadowOffset();
		},
		/** @language english
		 * Set the angle of the shadow.
		 * @method setAngle
		 * @param {int} angle the angle of the shadow.
		 * @since 1.6.0
		 * @public
		 */
		setAngle : function (angle) {
			this.angle = angle;
			this.setShadowOffset();
		},
		/** @language english
		 * Set the color of the shadow.
		 * @method setColor
		 * @param {int} color the color of the shadow.
		 * @since 1.6.0
		 * @public
		 */
		setColor : function (color) {
			this.shadowColor = color;
		},
		/** @language english
		 * Set the amount of blur.
		 * @method setBlur
		 * @param {int} blur the amount of blur。
		 * @since 1.6.0
		 * @public
		 */
		setBlur : function (blur) {
			this.shadowBlur = blur;
		}
	};
	for (var k in p) {
		LDropShadowFilter.prototype[k] = p[k];
	}
	return LDropShadowFilter;
})();