Flex中常用的经纬度坐标与墨卡托坐标转换代码

package util
{
	public class Coordinate
	{
		static var M_PI:Number=Math.PI;
		//经纬度转墨卡托
		// 经度(lon)，纬度(lat)		
		public static function lon2Mercator(lon:Number):Number
		{
			var x:Number = lon *20037508.342789/180;
			
			return x;
		}
		
		public static function lat2Mercator(lat:Number):Number
		{
			var y:Number = Math.log(Math.tan((90+lat)*M_PI/360))/(M_PI/180);
			y = y *20037508.34789/180;
			
			return y;
		}
		
		//墨卡托转经纬度
		
		public static function Mercator2Lon(mercatorX:Number):Number
		{
			var x:Number = mercatorX/20037508.34*180;

			return x;
		}
		
		public static function Mercator2Lat(mercatorY:Number):Number
		{
			var y:Number = mercatorY/20037508.34*180;
			y= 180/M_PI*(2*Math.atan(Math.exp(y*M_PI/180))-M_PI/2);

			return y;
		}
	}
}