Solr & Heatmap & Geotools

[Joseph Obernberger <jo...@lovehorsepower.com>]

Hi All - I've been working with geo tools to build a heat map based on 
location data coming back from Solr Cloud using these nifty feature 
where you can facet on location 
(https://issues.apache.org/jira/browse/SOLR-7005) and generate a raster.
I've been able to take this data and build a GridCoverage2D object and 
.show() that OK - works nice (even displays a nice map), but I don't 
know how to apply the HeatmapProcess to it.  What I've tried so far is:

HeatmapProcess process = new HeatmapProcess();
SimpleFeatureCollection sfc = null;
         try {
             sfc = FeatureUtilities.wrapGridCoverage(rasterCov);
         } catch (TransformException ex) {
             System.out.println("Error: "+ex);
         } catch (SchemaException ex) {
             System.out.println("Error: "+ex);
         }
         if (sfc == null) {
             System.out.println("Bummer");
             System.exit(1);
         }

         GridCoverage2D cov = process.execute(sfc, // data
                 1024, //radius
                 "0", // weightAttr
                 1, // pixelsPerCell
                 bounds, // outputEnv
                 1024, // outputWidth
                 1024, // outputHeight
                 monitor // monitor)
         );
         cov.show();

So far all I get is an empty frame.  Any tips, or links on how to use 
HeatmapProcess?  Anyone trying anything like this?
Thanks very much!

-Joe