var WGS84_SEMI_MAJOR_AXIS = 6378137.0;
var WGS84_ECCENTRICITY = 0.0818191913108718138;
var DEG2RAD=0.0174532922519943;
var PI=3.14159267;
var FORMAT_DEFAULT="image/png";
var MERC_ZOOM_DEFAULT = 20;
function dd2MercMetersLng(p_lng) {
	return WGS84_SEMI_MAJOR_AXIS * (p_lng*DEG2RAD);
}

function dd2MercMetersLat(p_lat) {
	var lat_rad = p_lat * DEG2RAD;
	return WGS84_SEMI_MAJOR_AXIS * Math.log(Math.tan((lat_rad + PI / 2) / 2) * Math.pow( ((1 - WGS84_ECCENTRICITY * Math.sin(lat_rad)) / (1 + WGS84_ECCENTRICITY * Math.sin(lat_rad))), (WGS84_ECCENTRICITY/2)));
}

CustomGetTileUrl=function(tile,zoom) {
	if (this.myMercZoomLevel == undefined) {
    	this.myMercZoomLevel = MERC_ZOOM_DEFAULT;
	}

	if (this.myFormat == undefined) {
    	this.myFormat = FORMAT_DEFAULT;
	}


	var lULP = new GPoint(tile.x*256,(tile.y+1)*256);
	var lLRP = new GPoint((tile.x+1)*256,tile.y*256);
	var lUL = G_NORMAL_MAP.getProjection().fromPixelToLatLng(lULP,zoom);
	var lLR = G_NORMAL_MAP.getProjection().fromPixelToLatLng(lLRP,zoom);

	//範囲のチェック
	if( this.myLatLngBounds != null ) {
		var thisBounds = new GLatLngBounds( lUL , lLR ); 
		if( !this.myLatLngBounds.intersects( thisBounds ) ) {
			return "img/space.png";
		}
	}

	//メルカトル変換
	if (this.myMercZoomLevel!=0 && map.getZoom() < this.myMercZoomLevel) {
		var lBbox=dd2MercMetersLng(lUL.x)+","+dd2MercMetersLat(lUL.y)+","+dd2MercMetersLng(lLR.x)+","+dd2MercMetersLat(lLR.y);
		var lSRS="EPSG:54004";
	} else {
		var lBbox=lUL.x+","+lUL.y+","+lLR.x+","+lLR.y;
		var lSRS="EPSG:4326";
	} 
	var lURL=this.myBaseURL;
	lURL+="&REQUEST=GetMap";
	lURL+="&SERVICE=WMS";
	lURL+="&VERSION=1.1.1";
	lURL+="&LAYERS="+this.myLayers;
	lURL+="&STYLES=";
	lURL+="&FORMAT="+this.myFormat;
	lURL+="&BGCOLOR=0xFFFFFF";
	lURL+="&TRANSPARENT=TRUE";
	lURL+="&SRS="+lSRS;
	lURL+="&BBOX="+lBbox;
	lURL+="&WIDTH=256";
	lURL+="&HEIGHT=256";
	lURL+="&reaspect=true";
	//document.write(lURL + "<br/>")
	//alert(" url is " + lURL);
	return lURL;
}

function customOpacity() { return this.myOpacity; }