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<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=0">
<meta name="apple-mobile-web-app-capable" content="yes">
<link rel="stylesheet" href="../theme/default/style.css" type="text/css">
<link rel="stylesheet" href="style.css" type="text/css">
<style type="text/css">
#controlToggle li {
list-style: none;
}
p {
width: 512px;
}
#options {
position: relative;
width: 512px;
}
#output {
float: right;
}
/* avoid pink tiles */
.olImageLoadError {
background-color: transparent !important;
}
</style>
<script src="../lib/OpenLayers.js"></script>
<script type="text/javascript">
var map, measureControls;
function init(){
map = new OpenLayers.Map('map');
var wmsLayer = new OpenLayers.Layer.WMS( "OpenLayers WMS",
"http://vmap0.tiles.osgeo.org/wms/vmap0?", {layers: 'basic'});
map.addLayers([wmsLayer]);
map.addControl(new OpenLayers.Control.LayerSwitcher());
map.addControl(new OpenLayers.Control.MousePosition());
// style the sketch fancy
var sketchSymbolizers = {
"Point": {
pointRadius: 4,
graphicName: "square",
fillColor: "white",
fillOpacity: 1,
strokeWidth: 1,
strokeOpacity: 1,
strokeColor: "#333333"
},
"Line": {
strokeWidth: 3,
strokeOpacity: 1,
strokeColor: "#666666",
strokeDashstyle: "dash"
},
"Polygon": {
strokeWidth: 2,
strokeOpacity: 1,
strokeColor: "#666666",
fillColor: "white",
fillOpacity: 0.3
}
};
var style = new OpenLayers.Style();
style.addRules([
new OpenLayers.Rule({symbolizer: sketchSymbolizers})
]);
var styleMap = new OpenLayers.StyleMap({"default": style});
// allow testing of specific renderers via "?renderer=Canvas", etc
var renderer = OpenLayers.Util.getParameters(window.location.href).renderer;
renderer = (renderer) ? [renderer] : OpenLayers.Layer.Vector.prototype.renderers;
measureControls = {
line: new OpenLayers.Control.Measure(
OpenLayers.Handler.Path, {
persist: true,
handlerOptions: {
layerOptions: {
renderers: renderer,
styleMap: styleMap
}
}
}
),
polygon: new OpenLayers.Control.Measure(
OpenLayers.Handler.Polygon, {
persist: true,
handlerOptions: {
layerOptions: {
renderers: renderer,
styleMap: styleMap
}
}
}
)
};
var control;
for(var key in measureControls) {
control = measureControls[key];
control.events.on({
"measure": handleMeasurements,
"measurepartial": handleMeasurements
});
map.addControl(control);
}
map.setCenter(new OpenLayers.LonLat(0, 0), 3);
document.getElementById('noneToggle').checked = true;
}
function handleMeasurements(event) {
var geometry = event.geometry;
var units = event.units;
var order = event.order;
var measure = event.measure;
var element = document.getElementById('output');
var out = "";
if(order == 1) {
out += "measure: " + measure.toFixed(3) + " " + units;
} else {
out += "measure: " + measure.toFixed(3) + " " + units + "<sup>2</" + "sup>";
}
element.innerHTML = out;
}
function toggleControl(element) {
for(key in measureControls) {
var control = measureControls[key];
if(element.value == key && element.checked) {
control.activate();
} else {
control.deactivate();
}
}
}
function toggleGeodesic(element) {
for(key in measureControls) {
var control = measureControls[key];
control.geodesic = element.checked;
}
}
function toggleImmediate(element) {
for(key in measureControls) {
var control = measureControls[key];
control.setImmediate(element.checked);
}
}
</script>
</head>
<body onload="init()">
<h1 id="title">OpenLayers Measure Example</h1>
<div id="tags">
measuring, geodesic, area, length, distance
</div>
<p id="shortdesc">
Demonstrates the measure control to measure distances and areas.
</p>
<div id="map" class="smallmap"></div>
<div id="options">
<div id="output">
</div>
<ul id="controlToggle">
<li>
<input type="radio" name="type" value="none" id="noneToggle"
onclick="toggleControl(this);" checked="checked" />
<label for="noneToggle">navigate</label>
</li>
<li>
<input type="radio" name="type" value="line" id="lineToggle" onclick="toggleControl(this);" />
<label for="lineToggle">measure distance</label>
</li>
<li>
<input type="radio" name="type" value="polygon" id="polygonToggle" onclick="toggleControl(this);" />
<label for="polygonToggle">measure area</label>
</li>
<li>
<input type="checkbox" name="geodesic" id="geodesicToggle" onclick="toggleGeodesic(this);" />
<label for="geodesicToggle">use geodesic measures</label>
</li>
<li>
<input type="checkbox" name="immediate" id="immediateToggle" onclick="toggleImmediate(this);" />
<label for="immediateToggle">use immediate measures</label>
</li>
</ul>
<p>Note that the geometries drawn are planar geometries and the
metrics returned by the measure control are planar measures by
default. If your map is in a geographic projection or you have the
appropriate projection definitions to transform your geometries into
geographic coordinates, you can set the "geodesic" property of the control
to true to calculate geodesic measures instead of planar measures.
Also you have the possibility to set the "immediate" property to true
to get a new calculated value once the mouse has been mooved.</p>
</div>
</body>
</html>
|
