topic Re: Georss feeds with multipart polygons in ArcGIS Online Questions

Georss feeds with multipart polygons

BenScott1 — Mon, 21 Oct 2013 04:18:50 GMT

I am finding that both ArcGIS Online and ArcGIS Viewer for flex do not support georss feeds with multi-part polygons. I have added a feed http://www.rfs.nsw.gov.au/feeds/majorIncidents.xml to a flex viewer and have also tried adding it to a layer in arcgis online. Where there are multipart polygons only one part is being displayed.

Interestingly, when I add the same feed to Google maps it displays correctly with all parts. Has anyone else encountered this? Is there a workaround?

Test arcgis online map:
http://bit.ly/1cMlZ3b

Google test - just paste http://www.rfs.nsw.gov.au/feeds/majorIncidents.xml into the search bar of google maps. You will see that the google one has many more polygons.

Cheers,
Ben

Re: Georss feeds with multipart polygons

MikeMinami — Tue, 22 Oct 2013 02:13:53 GMT

Currently we don't support this.
Can you provide a URL reference to multiple part geometries in the GeoRSS specification? Unfortunately, this is not my area of expertise and I'm not seeing much on this in doing a web search...

Thanks,

Mike

Re: Georss feeds with multipart polygons

BenScott1 — Thu, 24 Oct 2013 00:30:10 GMT

Hi Mike - The feed in the link above seems to have one point and one-many polygons for each item. The viewer for flex and arcgis online seems to display the point and the first polygon.

I have no control over how the feed is structured - it is a third party product. The georss specification at http://georss.org does not appear to provide specifics about whether one or many features are allowed per item, and I think that the problem is that the rfs have interpreted the specifications in creating their feed differently to the way it was interpreted by ESRI in developing those applications.

Interestingly, ESRI Australia have been investigating this - they have just put together a public fire incidents map at http://webmap.em.esriaustraliaonline.com.au/nswfiremap/. They got around the problem by bringing the feed into ArcMap using the data interoperability extension and then publishing it as a feature service. So arcmap/data interop and ArcGIS for Flex/ArcGIS Online seem to interpret the Georss standard differently.

Cheers,
Ben

Re: Georss feeds with multipart polygons

BenScott1 — Sun, 27 Oct 2013 21:55:57 GMT

Further to this - the method described above using data interop extension has been largely successful (thanks to Esri Australia), however where there are multiple polygons within on feed item that overlap (for example where a new fire boundary has been rapidly digitised over an old one), ArcGIS displays the overlapping area as a gap. I guess ArcGIS is treating it as a self-intersection or perhaps a ring in the data.