Hi everybody,<br><br>we stuck on some problem. We tried to move a marker as shown in the example below but after several zoom-in steps the marker suddenly disappears and reassigns by zooming out.<br><br>Here the entire code. We merged the two examples marker-shadow.html and draw-feature.html to get there. Does anyone have an idea?<br>
<br><html xmlns="<a href="http://www.w3.org/1999/xhtml">http://www.w3.org/1999/xhtml</a>"><br>  <head><br>    <title>OpenLayers: Vector Graphics with Shadows</title><br>    <link rel="stylesheet" href="../theme/default/style.css" type="text/css" /><br>
    <link rel="stylesheet" href="style.css" type="text/css" /><br>    <style type="text/css"><br>        .smallmap {<br>            width: 300px;<br>        }<br>        <br>
        .docs {<br>            padding: 0px 5px;<br>        }<br>        <br>        td {<br>            vertical-align: top;<br>        }<br>        <br>    </style><br>    <script src="../lib/OpenLayers.js" type="text/javascript"></script><br>
    <script type="text/javascript"><br>        <br>        var SHADOW_Z_INDEX = 10;<br>        var MARKER_Z_INDEX = 11;<br>        <br>        var DIAMETER = 200;<br>        var NUMBER_OF_FEATURES = 15;<br>
          var features = [];  <br>        var map, layer;   <br>            <br>        function init() {<br>            map = new OpenLayers.Map("map");<br>            <br>            layer = new OpenLayers.Layer.Vector(<br>
                "Marker Drop Shadows",<br>                {<br>                    styleMap: new OpenLayers.StyleMap({<br>                        // Set the external graphic and background graphic images.<br>                        externalGraphic: "../img/marker-gold.png",<br>
                        backgroundGraphic: "./marker_shadow.png",<br>                        <br>                        // Makes sure the background graphic is placed correctly relative<br>                        // to the external graphic.<br>
                        backgroundXOffset: 0,<br>                        backgroundYOffset: -7,<br>                        <br>                        // Set the z-indexes of both graphics to make sure the background<br>                        // graphics stay in the background (shadows on top of markers looks<br>
                        // odd; let's not do that).<br>                        graphicZIndex: MARKER_Z_INDEX,<br>                        backgroundGraphicZIndex: SHADOW_Z_INDEX,<br>                        <br>                        pointRadius: 10<br>
                    }),<br>                    isBaseLayer: false,<br>                    rendererOptions: {yOrdering: true}<br>                }<br>            );<br>            <br>                        var wmsLayer = new OpenLayers.Layer.WMS( "OpenLayers WMS",<br>
                    "<a href="http://labs.metacarta.com/wms/vmap0">http://labs.metacarta.com/wms/vmap0</a>?", {layers: 'basic'});<br>        <br>            map.addLayers([wmsLayer,layer]);<br>            <br>
            // Add a drag feature control to move features around.<br>            var dragFeature = new OpenLayers.Control.DragFeature(layer);<br>            <br>            map.addControl(dragFeature);<br>         map.addControl(new OpenLayers.Control.LayerSwitcher());<br>
                map.addControl(new OpenLayers.Control.MousePosition());<br>            <br>            dragFeature.activate();<br>                        <br>            map.zoomToMaxExtent();<br>            <br>            drawFeatures();<br>
        }<br>        <br>        function drawFeatures() {<br>            <br>            layer.removeFeatures(layer.features);<br>            <br>            // Create features at random around the center.<br>            var center = map.getViewPortPxFromLonLat(map.getCenter());<br>
            <br>            // Add the ordering features. These are the gold ones that all have the same z-index<br>            // and succomb to y-ordering.<br>            <br>            <br>   <br>                // Calculate a random x/y. Subtract half the diameter to make some<br>
 <br>                var pixel = new OpenLayers.Pixel(center.x, center.y);<br>                <br>                var lonLat = map.getLonLatFromViewPortPx(pixel);<br>                features.push(<br>                    new OpenLayers.Feature.Vector(<br>
                        new OpenLayers.Geometry.Point(lonLat.lon, lonLat.lat)<br>                    )<br>                );<br>            <br>            <br>            layer.addFeatures(features[0]);<br>        features[0].geometry.x = 12;<br>
        features[0].geometry.y = 7;<br>        <br>        }<br>        <br>    </script><br>  </head><br>  <body onload="init()"><br>        <h1 id="title">Marker Shadows using Background Graphics/Z-Indexes</h1><br>
<br>        <div id="tags"><br>        </div><br><br>        <p id="shortdesc"><br>           This example shows off marker shadows using background graphics and z-indexes. Move the features around to show the shadows' interaction.<br>
        </p><br>        <br>        <br><br><br>        <table><br>            <tr><br>                <td><br>                    <div id="map" class="smallmap"></div><br>
                </td><br>                <td><br><br>            </tr><br>            <tr><br>                <td><br>                    <button onclick="drawFeatures()">Redraw Features</button><br>
                </td><br>            </tr><br>        </table><br>        <br>        <br>    </body><br></html><br><br>Regards, mehmet<br>