function jumpTo(lon, lat, zoom) {
    var x = Lon2Merc(lon);
    var y = Lat2Merc(lat);
    map.setCenter(new OpenLayers.LonLat(x, y), zoom);
    return false;
}

function Lon2Merc(lon) {
    return 20037508.34 * lon / 180;
}

function Lat2Merc(lat) {
    var PI = 3.14159265358979323846;
    lat = Math.log(Math.tan( (90 + lat) * PI / 360)) / (PI / 180);
    return 20037508.34 * lat / 180;
}





function addMarker(layer, lon, lat, popupContentHTML, iconId) {

    var ll = new OpenLayers.LonLat(Lon2Merc(lon), Lat2Merc(lat));
    var feature = new OpenLayers.Feature(layer, ll);

    feature.closeBox = true;
    feature.popupClass = OpenLayers.Class(OpenLayers.Popup.FramedCloud, {minSize: new OpenLayers.Size(300, 180) } );
    feature.data.popupContentHTML = popupContentHTML;
    feature.data.overflow = "hidden";

    var size = new OpenLayers.Size(icons[iconId][1],icons[iconId][2]);
    var offset = new OpenLayers.Pixel(-(size.w*icons[iconId][3]), -(size.h*icons[iconId][4]));
    feature.data.icon = new OpenLayers.Icon(icons[iconId][0],size,offset);
    var icon = new OpenLayers.Icon(icons[iconId][0],size,offset);



    var marker = new OpenLayers.Marker(ll,icon);
    marker.feature = feature;

    var markerClick = function(evt) {
        if (this.popup == null) {
            this.popup = this.createPopup(this.closeBox);
            map.addPopup(this.popup);
            this.popup.show();
        } else {
            this.popup.toggle();
        }
        OpenLayers.Event.stop(evt);
    };
    marker.events.register("mousedown", feature, markerClick);


    layer.addMarker(marker);
    map.addPopup(feature.createPopup(feature.closeBox));
    	    feature.popup.hide();
	    feature.popup.clicked = false;

}




function getCycleTileURL(bounds) {
   var res = this.map.getResolution();
   var x = Math.round((bounds.left - this.maxExtent.left) / (res * this.tileSize.w));
   var y = Math.round((this.maxExtent.top - bounds.top) / (res * this.tileSize.h));
   var z = this.map.getZoom();
   var limit = Math.pow(2, z);

   if (y < 0 || y >= limit)
   {
     return null;
   }
   else
   {
     x = ((x % limit) + limit) % limit;

     return this.url + z + "/" + x + "/" + y + "." + this.type;
   }
}






/*
 *
 * Creates a new marker icon
 *
 * using the icons-array (defined in the html-file)
 *
 * index
 * 0    address to the image
 * 1    width of the image
 * 2    height
 * 3    factor by which the image should be offset horizontally
 * 4    factor by which the image should be offset vertically
 *
 * please see the icon array itself for examples of values
 */
function makeIcon(iconId) {
    var size = new OpenLayers.Size(icons[iconId][1],icons[iconId][2]);
    var offset = new OpenLayers.Pixel(-(size.w*icons[iconId][3]), -(size.h*icons[iconId][4]));
    var icon = new OpenLayers.Icon(icons[iconId][0],size,offset);
    return icon;
}