Install Workflow external scripts and create bash script to generate thumbnail for 3d models.
For generate thumbnail from obj, stl and x3d using minirender.
For 3mf, amf and step a temporary stl file is creating by PrusaSlicer.
simple and nice solution.
With the File actions app files_scripts, you can solve that without an external bash script.
In addition, you can create a thumbnail at any time, but it can also be generated event-controlled via cron, as with workflow_script. Advantage with files_scripts: data such as cloud_data_path and occ_path are automatically recognized or not required.
If triggered via actions_script in the context menu, you could also adjust the values for tilt and yaw, depending on the object, which is an absolute added value in my opinion.
Con: You must learn lua script, but that is not too much of an effort
Replaced prusaslicer by gmsh to get support iges format.
sudo apt install gmsh
Could you maybe give us some pointers to tutorials or example code of how to do this?
I tried googling for other custom thumbnail generators but non of them seem to be using your approach?
Did you study the files_scripts App docs? You have to dive into it a bit and deal with lua script.
Let’s see, maybe if I feel like doing it in the next few days, then I’ll make you a small example, but I’m not promising anything, I’ve got a lot to do at the moment. But actually, everything is very well documented with the sample scripts that come with the app and the scripting API and manuals.
Hey,
if i want to add the rule, i get configuration errors with %n and without.
I cant find the Problem, log is empty.
Ideas?
Thanks
You have to select an event
es ist kein Ereignis ausgewählt
After the “Wenn” you have to select an option from the dropdown menu.
Oh my god i,m so blind. i need holidays!!! thank you! 
How can I install minirender ?
I tried but it’s seems don’t work for me…
Maybe I made a misstake…
My Workflow external scripts:
My minirender-master directory:
My 3dmodel_thumb.sh (with chmod +x):
As far as I can see, your mistake is the variable minirender_path. You have:
minirender_path="/var/www/nextcloud/ext_script/minirender-master"
but that is only the directory. The variable must point to the compiled binary, so in your case it has to be:
minirender_path="/var/www/nextcloud/ext_script/minirender-master/minirender"
to make the magic happen
Much luck
@ernolf Thanks you for your reply but it doesnt work 
Did you try if the binary you compiled works (without the script)?
Is this needed to make thumbnails work in Windows file browser as well? They are removed/disappear as soon as Nextcloud syncs them to the server. I don’t need them to show up in the web Nextcloud, so I am unsure if I need this workaround or is some setting in NC set incorrectly that causes thumbnails to disappear, even from Windows side.
For some odd reason Solidowrks part files, .SLDPRT, retain their thumbnail, but every other CAD file loses it, when placed in a NC sync folder.