图层滑动
图层滑动贴图的示例。
<!DOCTYPE html><html>
<head>
<title>Layer Swipe</title>
<link rel="stylesheet" href="https://openlayers.org/en/v5.1.3/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>
</head>
<body>
<div id="map" class="map"></div>
<input id="swipe" type="range" style="width: 100%">
<script>
import Map from 'ol/Map.js';
import View from 'ol/View.js';
import {defaults as defaultControls} from 'ol/control.js';
import TileLayer from 'ol/layer/Tile.js';
import BingMaps from 'ol/source/BingMaps.js';
import OSM from 'ol/source/OSM.js';
var osm = new TileLayer({
source: new OSM()
});
var bing = new TileLayer({
source: new BingMaps({
key: 'Your Bing Maps Key from http://www.bingmapsportal.com/ here',
imagerySet: 'Aerial'
})
});
var map = new Map({
layers: [osm, bing],
target: 'map',
controls: defaultControls({
attributionOptions: {
collapsible: false
}
}),
view: new View({
center: [0, 0],
zoom: 2
})
});
var swipe = document.getElementById('swipe');
bing.on('precompose', function(event) {
var ctx = event.context;
var width = ctx.canvas.width * (swipe.value / 100);
ctx.save();
ctx.beginPath();
ctx.rect(width, 0, ctx.canvas.width - width, ctx.canvas.height);
ctx.clip();
});
bing.on('postcompose', function(event) {
var ctx = event.context;
ctx.restore();
});
swipe.addEventListener('input', function() {
map.render();
}, false);
</script>
</body></html>