swissnames 3d-tiles are in .vctr format which is not conforming to cesium standard

[Xavier W.]

Dear all,

Since I didn't get any traction in my GitHub issue, let me post it here:

I have been trying to integrate the swissnames Cesium 3D tileset documented here in a third party plugin (3DTilesRendererJSfrom NASA) without any luck. I raised an issue for the plugin maintainer here and the conclusion was that your dataset is using a format (.vctr) which is not standard according to the current 3D-tiles specs.

When involved in the discussion, Sean Lilley, Cesium 3D team lead, proposed in his comment to use "glTF + EXT_structural_metadata + EXT_meshopt_compression" instead.

Is there any particular reason you are using this non-standard format for this 3D tileset? Any chance you can generate a new 3D tileset conforming to the 3D tiles specs? If yes, can you provide a timeline?

Also, I noticed that only the dataset from 16.07.2018 seems to be available. At least, this is what is documented in the docs, but I noticed that are quite incomplete or even outdated on some topics, so I might be wrong.

Thank you very much in advance for your answer!

[GeoAdminCh API]

Hello,

The swissnames3D tiles where created as .vctr. We have updated the layer, because the selection of geographical names we have here didn’t change a lot. We are using it in our 3D viewer and it does the job. We will have a look to update the format and the content. We cannot say if and when we will make a change. You say that the content is imcomplete or wrong. Do you have exemples of missing elements ? 

Thank you in advance for your answer.

Best regards,

Helpdesk feredal geoportal

[Xavier W.]

Hi,

Thank you for your reply.

I am looking at this again and would like to precise that I never said the content of the tiles is incomplete or wrong. I am just saying that the format of the 3d-tiles (i.e. the way they are proposed to users) is not according to current state of the art.

As Sean Lilley, Cesium 3D team lead, said in the comment I am mentioning above, "the vctr format was created for storing 3D vector data but nowadays [he] would try to use glTF for this. [He] did some experiments a few years ago and saw pretty good results switching to glTF + EXT_structural_metadata + EXT_meshopt_compression."

I am therefore proposing to adopt these changes, as the "vector" format for 3d tiles was never formally completed by Cesium and has therefore never really been a standard.

Does it work? Yes. Is it optimal? No. swisstopo accustomed me to being at the top of new technologies and here a very old standard is used.

I am not expecting a format change in a matter of days or weeks, but please consider it for the evolution of the product.

Thanks!

Xavier Willemin