mirror of
https://github.com/Viglino/ol-ext.git
synced 2026-01-25 17:36:21 +00:00
163 lines
5.1 KiB
HTML
163 lines
5.1 KiB
HTML
<!DOCTYPE html>
|
|
<html>
|
|
<head>
|
|
<!--
|
|
Copyright (c) 2015-2018 Jean-Marc VIGLINO,
|
|
released under CeCILL-B (french BSD like) licence: http://www.cecill.info/
|
|
-->
|
|
<title>ol-ext: Elevation layer</title>
|
|
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
|
|
|
|
<meta name="description" content="[ol-ext] Elevation map" />
|
|
<meta name="keywords" content="ol, openlayers, layer, elevation, altitude, geoportail" />
|
|
|
|
<!-- jQuery -->
|
|
<script type="text/javascript" src="https://code.jquery.com/jquery-1.11.0.min.js"></script>
|
|
|
|
<!-- Openlayers -->
|
|
<link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/ol@latest/ol.css" />
|
|
<script type="text/javascript" src="https://cdn.jsdelivr.net/npm/ol@latest/dist/ol.js"></script>
|
|
<script src="https://cdn.polyfill.io/v2/polyfill.min.js?features=requestAnimationFrame,Element.prototype.classList,URL,Object.assign"></script>
|
|
|
|
<!-- ol-ext -->
|
|
<link rel="stylesheet" href="../../dist/ol-ext.css" />
|
|
<script type="text/javascript" src="../../dist/ol-ext.js"></script>
|
|
<!-- Pointer events polyfill for old browsers, see https://caniuse.com/#feat=pointer -->
|
|
<script src="https://unpkg.com/elm-pep"></script>
|
|
|
|
<!-- filesaver-js -->
|
|
<script type="text/javascript" src="https://cdn.rawgit.com/eligrey/FileSaver.js/aa9f4e0e/FileSaver.min.js"></script>
|
|
|
|
<link rel="stylesheet" href="../style.css" />
|
|
<style>
|
|
pre {
|
|
padding: .2em 1em;
|
|
margin: .2em 1em;
|
|
background: #ddd;
|
|
width: auto;
|
|
display: inline-block;
|
|
}
|
|
</style>
|
|
</head>
|
|
<body >
|
|
<a href="https://github.com/Viglino/ol-ext" class="icss-github-corner"><i></i></a>
|
|
|
|
<a href="../../index.html">
|
|
<h1>ol-ext: x-bil elevation layer</h1>
|
|
</a>
|
|
<div class="info">
|
|
This example use a TileWMS layer with an x-bil (Band Interleaved by Line) image format and a
|
|
<a href="https://openlayers.org/en/latest/apidoc/module-ol_Tile.html#~LoadFunction">tileLoadFunction</a>
|
|
to encode altitude as RGB pixels.
|
|
<br/>
|
|
The following equation will decode pixel values to height values:
|
|
<br/>
|
|
<pre>height = -12000 + ((R * 256 * 256 + G * 256 + B) * 0.01)</pre>
|
|
<br/>
|
|
It ensure a 2 digit precision and a maximum deep watter trench up to -12000 m.
|
|
<br/>
|
|
Use the <i>ol.ext.getElevationFromPixel</i> function to get elevation from RGB pixel value.
|
|
</div>
|
|
|
|
<!-- DIV pour la carte -->
|
|
<div id="map" style="width: 100%; height: 600px;"></div>
|
|
<label>
|
|
<input type="checkbox" onchange="hide.setDisplay(this.checked)"/>
|
|
display elevation map
|
|
</label>
|
|
|
|
<script>
|
|
|
|
var plan = new ol.layer.Geoportail({
|
|
layer: 'GEOGRAPHICALGRIDSYSTEMS.PLANIGNV2',
|
|
className: 'plan',
|
|
});
|
|
|
|
// The map
|
|
var map = new ol.Map ({
|
|
target: 'map',
|
|
view: new ol.View ({
|
|
zoom: 0,
|
|
center: [951487, 3467896]
|
|
}),
|
|
layers: [ plan ]
|
|
});
|
|
map.addControl(new ol.control.LayerSwitcher());
|
|
map.addControl(new ol.control.Permalink({ visible: false }));
|
|
map.addControl(new ol.control.SearchNominatim({ zoomOnSelect: 16 }));
|
|
|
|
// A set of elevation layers
|
|
var layers = [
|
|
{
|
|
title: 'MNT SRTM3',
|
|
url: 'https://data.geopf.fr/wms-r/wms',
|
|
layer: 'ELEVATION.ELEVATIONGRIDCOVERAGE.SRTM3',
|
|
//extent: [ -20037554.725947514, -8625918.87376409, 20037554.725947514, 8625918.87376409 ]
|
|
},{
|
|
title: 'MNS',
|
|
url: 'https://data.geopf.fr/wms-r/wms',
|
|
layer: 'ELEVATION.ELEVATIONGRIDCOVERAGE.HIGHRES.MNS',
|
|
extent: [ -578959.605490584, 5203133.393641367, 921974.2487313666, 6643289.75487211 ]
|
|
}, {
|
|
title: 'MNT-RGE-Alti',
|
|
url: 'https://data.geopf.fr/wms-r/wms',
|
|
layer: 'ELEVATION.ELEVATIONGRIDCOVERAGE.HIGHRES',
|
|
extent: [ -7007874.496280316, -1460624.494037931, 5043253.3127169, 6639937.650114076 ]
|
|
}, {
|
|
title: 'MNT BDAlti V1',
|
|
url: 'https://data.geopf.fr/wms-r/wms',
|
|
layer: 'ELEVATION.ELEVATIONGRIDCOVERAGE',
|
|
extent: [ -7007874.496280316, -1460624.494037931, 5043253.3127169, 6639937.650114076 ]
|
|
}
|
|
];
|
|
|
|
// Add tile layer
|
|
var layer = layers[0]
|
|
var elev = new ol.layer.Tile ({
|
|
title: layer.title,
|
|
displayInLayerSwitcher: false,
|
|
extent: layer.extent,
|
|
minResolution: 0,
|
|
maxResolution: 197231.79878968254,
|
|
source: new ol.source.TileWMS({
|
|
url: layer.url,
|
|
projection: 'EPSG:3857',
|
|
attributions: [ 'Geoservices-IGN' ],
|
|
crossOrigin: 'anonymous',
|
|
params: {
|
|
LAYERS: layer.layer,
|
|
FORMAT: 'image/x-bil;bits=32',
|
|
VERSION: '1.3.0'
|
|
}
|
|
})
|
|
});
|
|
map.addLayer(elev);
|
|
|
|
// Tile load function to convert elevation
|
|
var alti = ol.ext.imageLoader.elevationMap();
|
|
elev.getSource().setTileLoadFunction(alti);
|
|
|
|
// Hide the layer (but keep it on the map)
|
|
var hide = new ol.filter.CSS({ display: false });
|
|
elev.addFilter(hide);
|
|
|
|
// Prevent layer smoothing
|
|
elev.once('prerender', function(evt) {
|
|
evt.context.imageSmoothingEnabled = false;
|
|
evt.context.webkitImageSmoothingEnabled = false;
|
|
evt.context.mozImageSmoothingEnabled = false;
|
|
evt.context.msImageSmoothingEnabled = false;
|
|
});
|
|
|
|
// Add a popup to display elevation
|
|
var popup = new ol.Overlay.Tooltip();
|
|
map.addOverlay(popup)
|
|
map.on('pointermove', function(e) {
|
|
var pix = elev.getData(e.pixel);
|
|
var h = ol.ext.getElevationFromPixel(pix);
|
|
popup.setInfo(h > -5000 ? h.toFixed(2)+' m' : '');
|
|
});
|
|
|
|
</script>
|
|
</body>
|
|
</html> |