[Talk-de] OpenLayers-Frage: Projektionssystem für Punkt?

Mo Feb 14 21:33:21 UTC 2011

Ich weiß nicht, wie weit OpenLayers hier OT ist. In diesem Minimalbeispiel
erscheint der fünfzackige Stern nicht in dem anfänglichen Kartenausschnitt,
sondern am OSM-Südpol:

<html xmlns="http://www.w3.org/1999/xhtml">
  <head>
    <style type="text/css">
#map {
        width: 100%;
        height: 80%;
        border: 0px;
        padding: 0px;
        position: absolute;
     }
body {
        border: 0px;
        margin: 0px;
        padding: 0px;
        height: 100%;
     }
    </style>
    <script src="http://www.openlayers.org/api/OpenLayers.js"></script>
    <script src="http://www.openstreetmap.org/openlayers/OpenStreetMap.js"></script>
    <script type="text/javascript">
        <!--
        // complex map object
        var map;

 // Start position for the map (hardcoded here for simplicity,
 // but maybe you want to get from URL params)
 var lat = 48.49345;
 var lon = 8.71229;
 var zoom = 14;

        function init(){
            map = new OpenLayers.Map('map',
                    { maxExtent: new OpenLayers.Bounds(-20037508.34,-20037508.34,20037508.34,20037508.34),
                      numZoomLevels: 19,
                      maxResolution: 156543.0399,
                      units: 'm',
                      projection: new OpenLayers.Projection("EPSG:900913"),
                      displayProjection: new OpenLayers.Projection("EPSG:4326")
                    });

 //           var layerMapnik = new OpenLayers.Layer.OSM.Mapnik("Mapnik");
            var layerTah = new OpenLayers.Layer.OSM.Osmarender("Tiles at Home");

            map.addLayer(layerTah);

    //   Experimental layer

       /*
             * Blue style
             */

            var layer_style = OpenLayers.Util.extend({}, OpenLayers.Feature.Vector.style['default']);
            layer_style.fillOpacity = 0.8;

            var style_blue = OpenLayers.Util.extend({}, layer_style);
            style_blue.strokeColor = "blue";
            style_blue.fillColor = "blue";
            style_blue.graphicName = "star";
            style_blue.pointRadius = 10;
            style_blue.strokeWidth = 3;
            style_blue.rotation = 45;
            style_blue.strokeLinecap = "butt";

            var point = new OpenLayers.Geometry.Point(8.718685,48.475637);
	       var vectorLayer = new OpenLayers.Layer.Vector("Glyphs",
	              {projection: map.displayProjection});
		         var feature = new OpenLayers.Feature.Vector(
			    point,null, style_blue);
			       vectorLayer.addFeatures(feature);
			          map.addLayer(vectorLayer);

            map.addControl(new OpenLayers.Control.LayerSwitcher());

            var lonLat = new OpenLayers.LonLat(lon, lat).transform(map.displayProjection,  map.projection);
            if (!map.getCenter()) map.setCenter (lonLat, zoom);
        }
        // -->
    </script>
  </head>
  <body onload="init()">
    <div id="map"></div>
  </body>
</html>

-- 
Johannes Hüsing               There is something fascinating about science. 
                              One gets such wholesale returns of conjecture 
mailto:johannes at huesing.name  from such a trifling investment of fact.                
http://derwisch.wikidot.com         (Mark Twain, "Life on the Mississippi")