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Geoserver is drawing from a PostGIS database to generate a heatmap using this SLD extension. Leaflet then overlays the heatmap over the base layer.

Question: How can you determine the value at a particular spot on the heatmap? This value to display will be color ramp value X * constant C. In other words, how can we determine the color ramp value at that particular spot on the heatmap?

There's probably other methods of finding this value without using the heatmap's color ramp mapping.

enter image description here

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You could always 'cheat' and pull the layer from the pixel point on the rendered image that's returned (if you're using an html5 browser and tags). Then pull out the R, G,and B pixel values to reverse-determine the number...

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