Rhino error: Crashes when opening OBJ file

I have already discovered a work around for this issue but wanted to highlight this for the devs.

When opening an obj file by right clicking the file and opening with R6, the file opens fine. When setting your default to R6, then opening by double clicking, this error appears.


Slowing it down, it says the following:
“at Rhino.RhinoFileWatcher.Watch(String path, String filter)
The path is not of a legal form.”

There is no error file as I have to end task through the task manager.

I am not sure if this is becuse I am asking Rhino to open a file directly that is not a rhino file, or something else. To work around, I just use “open with” each time.

Hello - so far I cannot reproduce this here - I set Rhino 6 as the default for obj and it all seems to work - @tim - do you have an idea what might be happening?


Do you have the same problem with an OBJ that has no textures? This looks like it could be related to texture files. Can you post the obj/mtl any texture files that are used? Since we can’t duplicate this here with our own files we’ll need to see what’s different abut yours.

Nailed it on the head @tim, When the MTL. file is not in the associated folder there are no errors.

I attached a file here for reference. https://we.tl/t-eQv3cUrTHH

On our end, these OBJ files are generated out of Metashape. We process hundreds of these a month so streamlining the process from Metashape to a scaled/oriented object. With the MTL file in the folder, users are able to open the obj file and the texture file is automatically associated. When we use only the JPG, the user needs to drag/drop the file.

You get a crash? I do see the same exception that you get but not a crash. It even seems to load the texture.

I’ll look into this on Monday. Here’s a YouTrack issue you can check on to follow progress.

I have not gotten a crash report. It cycles through these lines in the command prompt without crashing. I end the task through task manager. I do realize it takes a bunch of ram up during its hate cycle.