topic Re: Getting activeMap extent coordinates after setting activeMap.spatialReference in Python Questions

Getting activeMap extent coordinates after setting activeMap.spatialReference

EricEagle — Tue, 22 Mar 2022 22:03:57 GMT

In ArcGIS Pro (2.9), I'm doing some processing work based on a mask I derive from the active map view.

The processor expects UTM-projected data. However, it might be that the user has not projected their map project to UTM, so I am trying to catch and handle that in the flow. Right now my code looks like this:

d = arcpy.Describe(raster_in) r_in_sr = d.spatialReference # Make sure data is not unprojected or in common GCS if r_in_sr.factoryCode in [4326, 3857, None]: raise ProjectionException("Input data not projected. Please ensure all inputs are projected and retry.") # Make sure the active map is set to same spatial reference as input layer p = arcpy.mp.ArcGISProject("CURRENT") m = p.activeMap m.spatialReference = r_in_sr # successfully switches active map coord system! # Now get the view extent view_extent = p.activeView.camera.getExtent() arcpy.AddMessage(view_extent) # Yields GCS Lat/Lons, not UTM! extent_poly = arcpy.Polygon( arcpy.Array( [ view_extent.lowerLeft, view_extent.lowerRight, view_extent.upperRight, view_extent.upperLeft, view_extent.lowerLeft ] ), spatial_reference=r_in_sr ).projectAs(r_in_sr) # neither of these sr's do anything, I still get GCS lat/lons mask = arcpy.CopyFeatures_management(extent_poly, os.path.join(scratch, "mask")) # scratch is arcpy.env.scratchGDB

The interesting thing here is that if I START the process with a UTM-projected active map, the whole thing works fine. I get extent coordinates in UTM.

If I start the process with a common GCS, the script does set the active map to a UTM coordinate system. But nothing I do seems to coerce the Polygon object to UTM: it still reports GCS Lat/Lon coordinates. Therefore when I call 'mask' on UTM-projected input layers, it throws an error and tells me the extent is wrong.

The amusing thing is, that if I simply re-run it after that, the script starts out with the active map in the UTM projection set from the previous attempt, and runs fine.

This feels like a bug, but I could definitely be doing something wrong, so I thought I'd check with the experts before I file it with our customer rep.

Re: Getting activeMap extent coordinates after setting activeMap.spatialReference

curtvprice — Tue, 22 Mar 2022 22:31:28 GMT

At the end of a very long thread, this may be a workaround:

https://community.esri.com/t5/arcgis-pro-questions/arcgis-pro-arcpy-how-to-refresh-the-map/m-p/1153373/highlight/true#M52737

Re: Getting activeMap extent coordinates after setting activeMap.spatialReference

EricEagle — Tue, 22 Mar 2022 23:13:02 GMT

Interesting! I’m away from my workstation but will give it a try tomorrow and report back.

Re: Getting activeMap extent coordinates after setting activeMap.spatialReference

JohannesLindner — Wed, 23 Mar 2022 07:31:16 GMT

Do it the other way around: instead of setting the map coordinate system, project the extent.

d = arcpy.Describe(raster_in) r_in_sr = d.spatialReference # Make sure data is not unprojected or in common GCS if r_in_sr.factoryCode in [4326, 3857, None]: raise ProjectionException("Input data not projected. Please ensure all inputs are projected and retry.") # Get the current view extent p = arcpy.mp.ArcGISProject("CURRENT") view_extent = p.activeView.camera.getExtent() arcpy.AddMessage(view_extent.polygon.spatialReference.factoryCode) arcpy.AddMessage(view_extent.polygon.firstPoint) # project view_extent; note that you don't have to construct the polygon yourself! extent_poly = view_extent.polygon.projectAs(r_in_sr) arcpy.AddMessage(extent_poly.spatialReference.factoryCode) arcpy.AddMessage(extent_poly.firstPoint)

Re: Getting activeMap extent coordinates after setting activeMap.spatialReference

EricEagle — Wed, 23 Mar 2022 19:49:25 GMT

This worked, thanks!