GetFeatureInfo example (image layer)

This example shows how to trigger WMS GetFeatureInfo requests on click for a WMS image layer.

Additionally map.forEachLayerAtPixel is used to change the mouse pointer when hovering a non-transparent pixel on the map.

getfeatureinfo, forEachLayerAtPixel
<!DOCTYPE html>
<html>
<head>
<title>GetFeatureInfo example (image layer)</title>
<script src="https://code.jquery.com/jquery-1.11.2.min.js"></script>
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.5/css/bootstrap.min.css">
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.5/js/bootstrap.min.js"></script>
<link rel="stylesheet" href="http://openlayers.org/en/v3.9.0/css/ol.css" type="text/css">
<script src="http://openlayers.org/en/v3.9.0/build/ol.js"></script>

</head>
<body>
<div class="container-fluid">

<div class="row-fluid">
  <div class="span12">
    <div id="map" class="map"></div>
    <div class="span4 offset4 pull-right">
      <div id="info" class="alert alert-success">
        &nbsp;
      </div>
    </div>
  </div>
</div>

</div>
<script>
var wmsSource = new ol.source.ImageWMS({
  url: 'http://demo.boundlessgeo.com/geoserver/wms',
  params: {'LAYERS': 'ne:ne'},
  serverType: 'geoserver',
  crossOrigin: ''
});

var wmsLayer = new ol.layer.Image({
  source: wmsSource
});

var view = new ol.View({
  center: [0, 0],
  zoom: 1
});

var map = new ol.Map({
  layers: [wmsLayer],
  target: 'map',
  view: view
});

map.on('singleclick', function(evt) {
  document.getElementById('info').innerHTML = '';
  var viewResolution = /** @type {number} */ (view.getResolution());
  var url = wmsSource.getGetFeatureInfoUrl(
      evt.coordinate, viewResolution, 'EPSG:3857',
      {'INFO_FORMAT': 'text/html'});
  if (url) {
    document.getElementById('info').innerHTML =
        '<iframe seamless src="' + url + '"></iframe>';
  }
});

map.on('pointermove', function(evt) {
  if (evt.dragging) {
    return;
  }
  var pixel = map.getEventPixel(evt.originalEvent);
  var hit = map.forEachLayerAtPixel(pixel, function(layer) {
    return true;
  });
  map.getTargetElement().style.cursor = hit ? 'pointer' : '';
});

</script>
</body>
</html>