Files
openlayers/examples/zoomLevels.html
crschmidt 7da6a3540e Merge the excellent documentation work done during foss4g into trunk. Many
thanks to all the contributors who helped put this together. 
I'm not exactly sure of what's going to happen with this, but for now,
at http://openlayers.org/dev/doc/examples.html you can see links to all the
examples *with descriptions*. Hooray!


git-svn-id: http://svn.openlayers.org/trunk/openlayers@5362 dc9f47b5-9b13-0410-9fdd-eb0c1a62fdaf
2007-12-08 14:21:53 +00:00

84 lines
2.8 KiB
HTML

<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<style type="text/css">
#map {
width: 512px;
height: 512px;
border: 1px solid black;
}
</style>
<script src="../lib/OpenLayers.js"></script>
<script type="text/javascript">
var lon = 50;
var lat = 0;
var zoom = 0;
var map, layer;
function init(){
OpenLayers.DOTS_PER_INCH = 72;
var options = {
// various ways of specifying similar things
// resolutions: [1.40625,0.703125,0.3515625,0.17578125,0.087890625,0.0439453125,0.02197265625,0.010986328125,0.0054931640625,0.00274658203125,0.00137329101],
// scales: [50000000, 10000000],
// maxResolution: 0.17578125,
// minResolution: 0.0439453125,
// maxScale: 10000000,
// minScale: 50000000,
// numZoomLevels: 5,
// units: "dd",
minResolution: "auto",
minExtent: new OpenLayers.Bounds(-1, -1, 1, 1),
maxResolution: "auto",
maxExtent: new OpenLayers.Bounds(-180, -90, 180, 90),
controls: [new OpenLayers.Control.MouseDefaults()]
};
map = new OpenLayers.Map( 'map' , options);
map.addControl(new OpenLayers.Control.PanZoomBar());
layer = new OpenLayers.Layer.WMS( "OpenLayers WMS",
"http://labs.metacarta.com/wms/vmap0", {layers: 'basic'});
map.addLayer(layer);
map.setCenter(new OpenLayers.LonLat(lon, lat), zoom);
}
</script>
</head>
<body onload="init()">
<h1 id="title">Zoom Level</h1>
<div id="tags">
</div>
<p id="shortdesc">
This example shows the use of the resolutions layer option on a number of layer types.
</p>
<div id="map"></div>
<div id="docs">
<p>
Set the extent of the viewable map using preset levels of scale available
to the user via the zoom slider bar. You can set the minimum, maximum
scales or resolutions, the number of levels in between and the minimum
and maximum geographic extents in your map's units.
</p>
<p>
Default units for Scale are in inches. Resolution is specified in map units
per pixel where the default map units are decimal degrees(dd).<br/>
scale = resolution * OpenLayers.INCHES_PER_UNIT[units] *
OpenLayers.DOTS_PER_INCH <br/>
You can either set the scale or the resolution, there is no need to set both.
</p>
<p>
You can do it with a ...
</p>
</div>
</body>
</html>