OpenLayers示例代码：设备定向
OpenLayers示例代码：设备定向
<!DOCTYPE html>
<html>
<head>
<title>Device Orientation</title>
<link rel="stylesheet" href="https://openlayers.org/en/v4.0.1/css/ol.css" type="text/css">
<!-- The line below is only needed for old environments like Internet Explorer and Android 4.x -->
<script src="https://cdn.polyfill.io/v2/polyfill.min.js?features=requestAnimationFrame,Element.prototype.classList,URL"></script>
<script src="https://openlayers.org/en/v4.0.1/build/ol.js"></script>
</head>
<body>
<div id="map" class="map"></div>
<label>
track changes
<input id="track" type="checkbox"/>
</label>
<p>
α : <code id="alpha"></code>
β : <code id="beta"></code>
γ : <code id="gamma"></code>
heading : <code id="heading"></code>
</p>
<script>
var projection = ol.proj.get('EPSG:3857');
var view = new ol.View({
center: [0, 0],
projection: projection,
extent: projection.getExtent(),
zoom: 2
});
var map = new ol.Map({
layers: [
new ol.layer.Tile({
source: new ol.source.OSM()
})
],
target: 'map',
controls: ol.control.defaults({
attributionOptions: /** @type {olx.control.AttributionOptions} */ ({
collapsible: false
})
}),
view: view
});
var deviceOrientation = new ol.DeviceOrientation();
function el(id) {
return document.getElementById(id);
}
el('track').addEventListener('change', function() {
deviceOrientation.setTracking(this.checked);
});
deviceOrientation.on('change', function() {
el('alpha').innerText = deviceOrientation.getAlpha() + ' [rad]';
el('beta').innerText = deviceOrientation.getBeta() + ' [rad]';
el('gamma').innerText = deviceOrientation.getGamma() + ' [rad]';
el('heading').innerText = deviceOrientation.getHeading() + ' [rad]';
});
// tilt the map
deviceOrientation.on(['change:beta', 'change:gamma'], function(event) {
var center = view.getCenter();
var resolution = view.getResolution();
var beta = event.target.getBeta() || 0;
var gamma = event.target.getGamma() || 0;
center[0] -= resolution * gamma * 25;
center[1] += resolution * beta * 25;
view.setCenter(view.constrainCenter(center));
});
</script>
</body>
</html>
说明：
OpenLayers示例代码：设备定向
