Free Geography Tools

Tixik Heatmaps – Lets you add a basic heat map to a simple Google Maps display. Create a “CSV” file of latitude/longitude pairs, with coordinates separated by a semi-colon, and each pair on a new line:

48.0043953135;0.2025604248

39.7117426603;3.4630966187

42.6976396896;2.8954124451

etc.

(Taken from the sample file).

Put the file online someplace, and then substitute its web address for “CSV_URL” in the Google Maps code below:

var tilelayer = new GTileLayer(new GCopyrightCollection(), 0, 17);
 tilelayer.getTileUrl = function(tile, zoom) {
   return 'http://api.tixik.com/scripts/tile.php?x='+tile.x+'&y='+tile.y+'&zoom='+zoom+'&csv=CSV_URL';
 };
 tilelayer.getOpacity = function() {return 0.7;}
 map.addOverlay(new GTileLayerOverlay(tilelayer));
Add this code to your Google Maps embed code, and get a basic heat map (sample map from Tixik website):

Fast, simple and basic – not a lot of options. Bit quirky/buggy, too – check out this zoomed-in area, which dropped some of the data (rest of the world looked fine:

Colors can also vary depending on the browser you use; the examples above are from Chrome, while the same map in Internet Explorer 8 looks like this:

For quick and dirty heatmaps with Google Maps, Tixik Heatmaps seems like a decent option. But there’s an option for use with other map backgrounds that’s more flexible in display options, data format, and embeddability; more on that tomorrow.


Related posts:

Embed Synchronized Google/Microsoft Virtual Earth Maps On Your Website/Blog
Thematic Data In Google Maps With Plug And Play Maps
KML Text Labels For Google Earth
Easy Heat Maps From Spreadsheet Data With OpenHeatMap
Heat Mapping In Google Maps