topic Re: How to create a heat map layer in Qt Maps SDK Questions

How to create a heat map layer

DarkRider — Mon, 06 Mar 2017 10:05:13 GMT

I want to use a heat map layer to visualize my data's density distribution over the map. I was thinking about using a ArcGISFeatureLayer, but I am not quite sure on how to use it for my purposes and if it is the right way. I am using ArcGIS SDK 10.2.6.

For example a heat map about the elevation of a specific area. How can I achieve that?

Is there some example code available?

Re: How to create a heat map layer

LucasDanzinger — Sat, 11 Mar 2017 00:09:20 GMT

We will have support for a HeatmapRenderer in an upcoming release. Most likely, 100 Update 2 (100.2). This will allow you to visualize a heat map from points like you see in ArcGIS Online. In the mean time, the only thing I can think to do as a workaround is the use the Local Server SDK to run a GP task that creates this. You could use one of the interpolation tools to create a raster, and then apply a renderer to the output raster to make it look like how you like - Local Server geoprocessing tools support—ArcGIS Runtime SDK for Qt | ArcGIS for Developers

It is definitely overkill for what you likely need, but it might get you the result you need in the meantime.

Re: How to create a heat map layer

ClayGinn — Mon, 17 Jul 2017 14:35:35 GMT

I realize that 100.1 just released, but any idea what the upcoming date might be for 100.2? This is one feature we really would like to have implemented.

Re: How to create a heat map layer

LucasDanzinger — Mon, 17 Jul 2017 15:15:22 GMT

100.1 supports heat maps if you create the map in ArcGIS Online and then open the map in Qt. It will display the heatmap just as it looks in the browser. There is no API yet to modify it programmatically on the client side. 100.2 is slated for the end of the year, but I am not certain if the client side renderer will be available or not.

Re: How to create a heat map layer

ClayGinn — Mon, 17 Jul 2017 15:54:05 GMT

Unfortunately that isn't an option for the way we have to work with the data. Here's hoping that the client side renderer will be available in the next release.

Thanks for the info.

Re: How to create a heat map layer

LucasDanzinger — Wed, 26 Jul 2017 19:27:36 GMT

As a workaround for now, you could create the renderer from JSON. An example workflow would be:

1) Create a WebMap in ArcGIS Online and configure the layer to have a heat map renderer

2) Open the Map in Runtime, iterate through the layers and find the one with the heat map renderer, and call toJson on it

3) Use that JSON (or a modified version of it) to construct a new Renderer by using fromJson, and set that renderer on a Feature Layer

It'll probably take some trial and error but it might at least get you going for the time being