Restricting layer rendering to a limited extent.
This example uses the layer.setExtent()
method to modify the extent of the overlay layer. Use the controls above to limit rendering based on an extent (approximate country bounds).
<!DOCTYPE html>
<html>
<head>
<title>Limited Layer Extent</title>
<link rel="stylesheet" href="https://openlayers.org/en/v4.6.4/css/ol.css" type="text/css">
<!-- The line below is only needed for old environments like Internet Explorer and Android 4.x -->
<script src=""></script>
<script src="https://openlayers.org/en/v4.6.4/build/ol.js"></script>
</head>
<body>
<div id="map" class="map"></div>
<button type="button" class="btn btn-default" id="India">India</button>
<button type="button" class="btn btn-default" id="Argentina">Argentina</button>
<button type="button" class="btn btn-default" id="Nigeria">Nigeria</button>
<button type="button" class="btn btn-default" id="Sweden">Sweden</button>
<script>
function transform(extent) {
return ol.proj.transformExtent(extent, 'EPSG:4326', 'EPSG:3857');
}
var extents = {
India: transform([68.17665, 7.96553, 97.40256, 35.49401]),
Argentina: transform([-73.41544, -55.25, -53.62835, -21.83231]),
Nigeria: transform([2.6917, 4.24059, 14.57718, 13.86592]),
Sweden: transform([11.02737, 55.36174, 23.90338, 69.10625])
};
var base = new ol.layer.Tile({
source: new ol.source.TileJSON({
url: 'https://api.tiles.mapbox.com/v3/mapbox.world-light.json?secure',
crossOrigin: 'anonymous'
})
});
var overlay = new ol.layer.Tile({
extent: extents.India,
source: new ol.source.TileJSON({
url: 'https://api.tiles.mapbox.com/v3/mapbox.world-black.json?secure',
crossOrigin: 'anonymous'
})
});
var map = new ol.Map({
layers: [base, overlay],
target: 'map',
view: new ol.View({
center: [0, 0],
zoom: 1
})
});
for (var key in extents) {
document.getElementById(key).onclick = function(event) {
overlay.setExtent(extents[event.target.id]);
};
}
</script>
</body>
</html>