Error when importing CityGML file

Hello,
I’m trying to import a citygml file on cesium ion using FME workbench and i’m facing some issues.

First i had a problem with geometry. Apparently cesium only support closed geometries (screen below).
image
When i tun a geometry validator on FME and kept only valid geometry i got a new error : Unsupported citygml node (screen below).


Could you please help figure out what the error is about.

Hi

It looks like the issue is the with the MultiGeometry tag as that is not supported by libcitygml, which Cesium’s pipelines depend on. Can you please replace all MultiGeometry tags with MultiSurface and then reupload this file?

Shehzan

I tried importing without the Multigeometry features and it worked. Thank you so much

Hi there. I am trying to import a CityJSON file on ION but, as there is no official support for such a file, I tried converting it to CityGML and uploading it afterward but to no avail. I tried the conversion with two different tools: citygml-tools and 3DCityDB (both officially supporting this kind of operation). The error ION gives me is in the tiling pipeline: ’ Missing spatial reference system (srsName) and no source SRS given (–source-srs).`. However, I checked the file and each building starts with something like this:

<gml:boundedBy>
  <gml:Envelope srsName="urn:ogc:def:crs:EPSG::6875" srsDimension="3">
    <gml:lowerCorner>6784419.238487907 5037379.480861005 0.0</gml:lowerCorner>
    <gml:upperCorner>6784432.31590414 5037395.061728267 6.0</gml:upperCorner>
  </gml:Envelope>
</gml:boundedBy>

First element is:

<CityModel xmlns:xAL="urn:oasis:names:tc:ciq:xsdschema:xAL:2.0" xmlns:bldg="http://www.opengis.net/citygml/building/1.0" xmlns:gml="http://www.opengis.net/gml" xmlns:app="http://www.opengis.net/citygml/appearance/1.0" xmlns="http://www.opengis.net/citygml/1.0" xmlns:gen="http://www.opengis.net/citygml/generics/1.0" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.opengis.net/citygml/building/1.0 http://schemas.opengis.net/citygml/building/1.0/building.xsd http://www.opengis.net/citygml/appearance/1.0 http://schemas.opengis.net/citygml/appearance/1.0/appearance.xsd http://www.opengis.net/citygml/1.0 http://schemas.opengis.net/citygml/1.0/cityGMLBase.xsd http://www.opengis.net/citygml/generics/1.0 http://schemas.opengis.net/citygml/generics/1.0/generics.xsd">

Can you help me solve this issue?

Hi @andreasscalas

Can you edit the SRS name to be just EPSG:6875. You may need to replace this in other parts of the file if the SRS is used elsewhere.

The SRS Name field is passed to GDAL to reproject. If GDAL doesn’t recognize them, either because of the prefixes or single vs double colons between the prefixes, then it throws an error. Using just EPSG:6875 should get accepted.

Thank you for your answer. I tried the proposed solution but received the same error. The asset ID is 2450549 if you want to check. Thank you again.