topic Features not being projected? in ArcGIS API for Silverlight Questions

Features not being projected?

AnthonyGrescavage — Thu, 01 Nov 2012 23:51:07 GMT

I have a point feature layer which does not appear to be properly projected. The map spatial reference is web mercator. The point layer is WKID 26717. Regardless of whether or not I specify a projection service on the layer, the points are slightly offset (same location either way). When using a query task to query the same feature and specifying the output spatial reference, it shows up in the proper location. What gives? Is there any way I can fix this?

Edit: The features appear to be offset by a consistent distance of roughly fifty feet east and slightly north of the actual location.

Re: Features not being projected?

AnthonyGrescavage — Mon, 05 Nov 2012 20:07:15 GMT

Edit 2:

I just noticed if I serve the same data up using an ArcGISDynamicMapServiceLayer, the data displays properly. It's ONLY when using a FeatureLayer that it is in the wrong location, regardless of whether or not the ProjectionService property is set.

Edit 3:

This only happens with point feature layers. There is a polygon feature layer in the same service that works as expected. There are also polyline feature layers in other services with the same basic configuration that also work as expected.

Re: Features not being projected?

AnthonyGrescavage — Fri, 09 Nov 2012 13:13:48 GMT

The issue was caused by the different spatial references. It seems that the appropriate transformation was being applied by some operations and not by others. We got around this issue by changing the data frame for the service to WGS84 and applying the appropriate transformation to the data frame. This way the features do not have to be projected on the client and everything matches up nicely.