When uploading polygon data from ArcMap it appears that features are losing precision in its vertices when it is displayed in ArcGIS Online.
It appears that the vertices of the polygons have lost a significant amount of precision resulting in misshaped areas and gaps along lines.
This article will address how we can work around this issue caused by a change made in the March 2014 update of ArcGIS Online. This change meant that editing was no longer enabled by default on feature services, and also meant that feature services that did not have editing enabled were generalized to help drawing performance/speed. It is this reason that the images are look as they do in our example above.
To stop feature services being generalized, you may do one of the following:
- Enable editing on the
feature service (My Content > <feature service name> > Edit)
- With editing still
disabled (i.e. not doing the above), add the feature service to a map with
editing enabled from the dropdown (for certain roles only):
Once you have done either of these, the feature service is
no longer disabled and the features draw as accurate as intended.