How to dynamically adjust zoom in Heatmap.js in OpenLayers

Figured it out... this isn't advertised in the documentation or anywhere on the internet that I could find.. however, here's how you control the radius in OpenLayers for those of you who need it. Let's keep it simple..

// create our heatmap layervar heatmap = new OpenLayers.Layer.Heatmap( "Heatmap Layer", map, osm, {visible: true, radius:50}, {isBaseLayer: false, opacity: 0.3, projection: new OpenLayers.Projection("EPSG:4326")});map.addLayers([heatmap]);

Now add the data:

heatmap.setDataSet(data);

Here's the key. You can do pretty much anything with this list of commands:

this.set("radius",value); //****this one solved my problemthis.set("element",value);this.set("visible",value); //deceiving! You have to access the canvas subclass to get it to workthis.set("max",value);this.set("gradient",value);this.set("opacity",value);this.set("width",value);this.set("height",value);this.set("debug",value);

So, for example, create a zoom event so the radius changes based on your radius function. For me, it was as simple as scaling the radius based on the ratio screen width(pixels)/screen width(meters). So now in your click event:

on zoom change: //pseudocodecanvas = heatmap.heatmap.get('canvas'); //this is the subclass I spoke of aboveif the zoom is above a certain value //pseudocodethencanvas.style.display = 'block'; //show the heatmap... you can also use heatmap.toggle() but this gives you more controlheatmap.heatmap.set('radius',zoomfunction[map.zoom]); //this dynamically updates the radius!!heatmap.updateLayer();elsecanvas.style.display = 'none';heatmap.updateLayer();

I hope this helps someone 'cause it drove me crazy!