Density map tutorial—Prototype, Google Maps API and the HeatMapAPI
13 July 2008 | Posted by Jeffrey Barke | 7 comments
I created a tutorial that will step one through how to create a density map with Prototype, the Google Maps API and the HeatMapAPI. The final product, a density map of liquor licenses in Milwaukee, WI, is below. While this map is based on real data, one limitation of the free HeatMapAPI is that only 100 data points can be submitted per call. Since there are approximately 1,300 liquor licenses in Milwaukee, this map isn't even close to accurate!
Creating a map like this takes four simple steps:
class HMGoogleOverlay
13 July 2008 | Posted by Jeffrey Barke | No comments
Note—HMGoogleOverlay is an undocumented method of the HeatMapAPI. The documentation here is unofficial and unauthorized, and it simply represents my best guess as to what HMGoogleOverlay is.
class HMGoogleOverlay
A HMGoogleOverlay augments the map with a density map image. It implements the GOverlay interface and thus is added to the map using the GMap2.addOverlay() method.
Constructor
| Constructor | Description |
|---|---|
HMGoogleOverlay(url) |
Creates a GOverlay. The url parameter is the URL (string) of the density map and is generated via the GEOHeatmap.GetURL() |
Note—HMGoogleOverlay does not have any public methods. It does not support either show() or hide().
