buffer.html 1.89 KB
<html xmlns="http://www.w3.org/1999/xhtml">
    <head>
        <title>OpenLayers Buffer Example</title>
        <link rel="stylesheet" href="../theme/default/style.css" type="text/css" />
        <link rel="stylesheet" href="style.css" type="text/css" />
        <script src="../lib/OpenLayers.js"></script>
        <script type="text/javascript">
            var lon = 0;
            var lat = 0;
            var zoom = 2;
            var map, layer;

            function init(){
                map = new OpenLayers.Map( 'map' );
                layer = new OpenLayers.Layer.WMS( "0 buffer: OpenLayers WMS",
                        "http://labs.metacarta.com/wms/vmap0",
                        {layers: 'basic'}, {'buffer':0} );
                map.addLayer(layer);
                layer = new OpenLayers.Layer.WMS( "1 buffer: OpenLayers WMS",
                        "http://labs.metacarta.com/wms/vmap0",
                        {layers: 'basic'}, {'buffer':1} );
                map.addLayer(layer);
                layer = new OpenLayers.Layer.WMS( "4 buffer: OpenLayers WMS",
                        "http://labs.metacarta.com/wms/vmap0",
                        {layers: 'basic'}, {'buffer':4} );
                map.addLayer(layer);
                map.addControl(new OpenLayers.Control.LayerSwitcher())
                map.setCenter(new OpenLayers.LonLat(lon, lat), zoom);
            }
        </script>
    </head>
    <body onload="init()">
        <h1 id="title">Buffer Example</h1>

        <div id="tags">
        </div>

        <p id="shortdesc">
            This example shows the use of the buffer layer option for any layer that inherits from OpenLayers.Layer.Grid.
        </p>

        <div id="map" class="smallmap"></div>

        <div id="docs">
            Use the buffer property to control how many tiles are included
            outside the visible map area. Default is 2.
        </div>
    </body>
</html>