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<html>
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<head>
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<title>Setting a visual Extent</title>
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<script src="../lib/OpenLayers.js"></script>
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</head>
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<body>
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<h1>Setting a Visual Extent</h1>
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<p>
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Because the ability to set the map to a given extent is limited by the
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current resolutions available, zoomToExtent will not always set the map to
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exactly the right extent. In order to visually annotate the actual extent,
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this example, will use the Boxes layer to visually describe the desired
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extent as well as setting the map extent.
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</p>
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<div style="width:100%; height:75%" id="map"></div>
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<script defer="defer" type="text/javascript">
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var map = new OpenLayers.Map('map');
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var bounds = new OpenLayers.Bounds(-45,-45, 0, 45);
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var wms = new OpenLayers.Layer.WMS( "OpenLayers WMS",
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"http://labs.metacarta.com/wms/vmap0", {layers: 'basic'} );
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map.addLayer(wms);
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map.zoomToExtent(bounds);
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var boxes = new OpenLayers.Layer.Boxes("boxes");
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var box = new OpenLayers.Marker.Box(bounds);
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boxes.addMarker(box);
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map.addLayer(boxes);
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</script>
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</body>
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</html>
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