WMS on Google Map, USGS topo example

Getting WMS data on Google Maps

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Querying your map for lat/lng points

In this map, I added a very simple function that asks what the lat/lng is for any point you click. On Roadlessland.org I sent this point data to a php file that then calculates the info needed for a WMS GetFeatureInfo query. You can see an example of that here.

Here is the code for the map on this page:

<script type="text/javascript"> // best to declare your map variable outside of the function so that you can access it from other functions var map; function initialize() { if (GBrowserIsCompatible()) { // set up the map map = new GMap2(document.getElementById("map_canvas")); // set up your wms layer var tile_roadless; tile_roadless= new GTileLayer(new GCopyrightCollection(""),1,17); // these are the layers from your mapserver map file tile_roadless.myLayers = 'ira_fill2,ira_line,wild_hatch'; tile_roadless.myMercZoomLevel=5; tile_roadless.myFormat='image/gif'; // this is the address of your mapserver map tile_roadless.myBaseURL= 'http://thewildwoodstudios.com/cgi-bin/mapserv?map=../roadlessland/maps/ira.map&'; // this is the function performed by John Deck's script tile_roadless.getTileUrl=CustomGetTileUrl; // this specifies the opacity of your layer tile_roadless.getOpacity = function() {return 1.0;} map.addControl(new GLargeMapControl()); map.addControl(new GMapTypeControl()); // set the location of the map map.setCenter(new GLatLng(35.846760876811366, -106.03317260742188), 10); // add wms layer with GTileLayerOverlay var MapserverLayer = new GTileLayerOverlay(tile_roadless); map.addOverlay(MapserverLayer); // add a function that listens for a click on the map and records the lat/lng from that point // this function calls another function that I call get_point() click_listen = GEvent.addListener(map, 'click', function(overlay,latlng) { var info = latlng.lat() + ', ' + latlng.lng(); map.openInfoWindow(latlng, info); }); } } </script>