Creating an AppearanceAssetElement through the RevitAPI with a texture that is located on Autodesk Docs or BIM360

[MartijnKalec]

Dear RevitAPI forum,

I've been searching on the API forum, API documentation and thebuildingcoder blogposts, but couldn't find the answer to my question anywhere. So I decided to create this post.

The question I have: how can I create an AppearanceAssetElement through the RevitAPI with a texture that is located on Autodesk Docs?

I already know how I can create the AppearanceAssetElement, but the part I'm struggling with is how to use a path that is pointing to Autodesk Docs, instead of a local absolute path.

My investigation up to now:

When I'm using the Material browser UI, I can simply change the texture location. By selecting a texture that is stored on Autodesk Docs, it recognizes that it's stored on Autodesk Docs and creates the ExternalResourceReference.

When I use the RevitLookup add-in (great tool btw!), I can confirm that I see both the ExternalReference pointing to Autodesk Docs, and the local absolute path on my disk:

Same goes for using the API. I can get both the ExternalResourceReference and the local absolute path to the texture (kinda in the same way as you would edit the path as you can read in this blog https://thebuildingcoder.typepad.com/blog/2017/11/modifying-material-visual-appearance.html).

And after doing some further research, I was able to find out how I could create an ExternalResourceReference from an absolute path on the user's PC.

But now the final step would be to create of modify an existing Material/AppearanceAssetElement to use this ExternalResourceReference.

I know that I can modify the path parameter in the AppearanceAssetElement. But as far as I can see, that would make it an absolute path on the machine, instead of a path to Autodesk Docs that multiple users can use. However, I don't see any way to edit the ExernalResourceReference the texture is using. Only how to get an already assigned ExternalResourceReference within the AppearanceAssetElement.

Is this even possible within the RevitAPI? Am I missing something obvious?

[jeremy_tammik]

Wow! Great research, brilliant question. Thank you for that. Tricky, maybe? I asked the development team for you. 

[MartijnKalec]

Thanks Jeremy! I'll await the response from the developers.

[jeremy_tammik · Accepted solution]

Good news from the development team: The ExternalResourceReference for the material texture feature supports the AppearanceAssetElement editing API; to set the path of a property, just set it to your local desktop connector local cache path (absolute path). Revit will create the external reference for it automatically. So, there's no need to create the external reference manually. Just note that the ExternalResourceReference support for material texture starts from Revit 2023.

[MartijnKalec]

Hi Jeremy,

Thanks a lot, just tried it and it seems to work!

[jeremy_tammik]

Glad to hear it. Thank you for confirming!