Transparency problem citygml

Hey, I’m experincing problems with the texture on my CityGML buildings. They are transparant. The intresting thing is that when I have them i KMZ format they are working fine. Here is a picture:

I found this thread https://community.cesium.com/t/3d-tiles-transparent-texture-issue/5516 but I can’t really work it out. And I don’t know if it’s a problem/bug in Cesium or if something has gone wrong in the creation process from my part. But both CityGML and KMZ are created from the same data. I have also converted the KMZ to CityGML but nothing changes. Any help or “pointing in the right direction” is appricated!

Thanks
Albin

Hi there,

Can you explain how the CityGML dataset was created? Was it converted to 3D Tiles before loading it into CesiumJS? If so, did you use Cesium ion or another tool?

Hey,

They are created through FME, read from OBJ → CityGMLGeometrySetter → written to building in CityGML, I have the buildings stored in ion and streamed from there to js. The process of creating the buildings consists of multiple scripts. The one above is the last part of the script. Also interesting is that the texture may appear to be inverted or “inside out”, if you look from the build from underneath the texture is not transparent.

Thanks

Hi @Albnas,

I think there is something happening before FME writes out the CityGML files.
Maybe you can use the “Orientor” transformer with orientation type “reverse” as a workaround.

Best, Lennart

Hey @lennart.imberg ,

What a tip, thank you very much! The workaround works perfectly, but I still wonder what causes the flip of textures. The transformer can be used before CityGMLGemetrySetter or after, either way it works.

Thanks, Albin