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Hi I am trying to generate heatmap using Geoserver Transformation SLD. as mentioned on the page, It requires few parameters:

  1. data
  2. weightAttr
  3. radiusPixels
  4. pixelsPerCell
  5. outputBBOX
  6. outputWidth and
  7. outputHeight

I am able to use it by specifying these parameters directly in SLD as default parameters. But i am not able to pass it as OpenLayers request. There is my code:

    var layer = new OpenLayers.Layer.WMS("Heat Map",
        layers: 'work:cbsa_pop', 
        format: "image/png",
        transparent: "true",
        maxExtent: new OpenLayers.Bounds(-124.269,32.545,-114.354,41.956),
        projection: new OpenLayers.Projection("EPSG:4326"),
        BBOX:new OpenLayers.Bounds(-124.269,32.545,-114.354,41.956),

This way it is not accepting any of the parameter. Any guidance will be helpful.

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please show the full error – iant Jun 23 '13 at 18:52
@iant : It is not giving any error but I am also not getting image which in other case (SLD with default specification), I am getting proper Heatmap. – apaleja Jun 23 '13 at 19:23

Look at the "env" filter function, you can pass parameters to it via the env=k1:v1;k2:v2 request parameter.

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I tried that way but i am getting error .. Unexpected token = – apaleja Jun 23 '13 at 14:04

I'm having the same problem. It seems that with this URL (from fresh Geoserver 2.2):,41.360256530762,-70.498977111817,42.523655578614&WIDTH=780&HEIGHT=330&weightAttr=FAMILIES

Adding in &weightAttr=FAMILIES should tell it to use the FAMILIES parameter for weighting

But I get the exact same image as if I didn't use that value. Likewise if I add &ENV=weightAttr:FAMILIES

Any ideas?

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