/*
  等比缩放
  as1984 - qq:38657783
  20091221
  请注意包路径，我的as包都放在tools目录下。所以包的路径是 tools
  如果你的路径不一样，请注意修改
*/
package tools
{
	public class imgzoom {
		
		// Static table initialization
		private var isZoom:Boolean;//是否缩放
		private var srcWidth:Number;//原始宽
		private var srcHeight:Number;//原始高
		private var maxWidth:Number;//限制宽
		private var maxHeight:Number;//限制高
		private var newWidth:Number;//新宽
		private var newHeight:Number;//新高
		
		public function imgzoom(srcWidth:Number,srcHeight:Number,maxWidth:Number,maxHeight:Number):void
		{
			this.srcWidth=srcWidth;
			this.srcHeight=srcHeight;
			this.maxWidth=maxWidth;
			this.maxHeight=maxHeight;
			if(this.srcWidth>0 && this.srcWidth>0){
				this.isZoom=true;
			}else{
				this.isZoom=false;
			}
			conductimg();
		}
		public function width():Number{
			return Number(this.newWidth.toFixed(2));
		}
		public function height():Number{
			return Number(this.newHeight.toFixed(2));
		}
		private function conductimg():void{
			if(this.isZoom){
				if(this.srcWidth/this.srcHeight>=this.maxWidth/this.maxHeight){
					if(this.srcWidth>this.maxWidth){
						this.newWidth=this.maxWidth;
						this.newHeight=(this.srcHeight*this.maxWidth)/this.srcWidth
					}else{
						this.newWidth=this.srcWidth;
						this.newHeight=this.srcHeight;
					}
				}else{
					if(this.srcHeight>this.maxHeight){
						this.newHeight=this.maxHeight;
						this.newWidth=(this.srcWidth*this.maxHeight)/this.srcHeight
					}else{
						this.newWidth=this.srcWidth;
						this.newHeight=this.srcHeight;
					}
				}
			}else{
				this.newWidth=0;
				this.newHeight=0;
			}
		}
	}
}