Hello,

I'm trying to get relative paths to work with the Arnold Image node. It seems like unlike Solaris native nodes, the path on the image node is not being converted to relative paths by the Output processor on the USD ROP node. Any paths just get converted to absolute paths. Is there anything I have to do to make that work?

I attached a small example file and usda to show what I mean.

Thanks!
Beat

What version of Houdini are you in? I had this problem a bit ago and if I remember correctly I ended up stepping back a version from Hou 19 to 18 and it was kept relative by the ROP. This may be an Arnold bug. Arnold 7 has been wildly frustrating. I think the HtoA for Hou 19 is still pretty buggy.

Ah thank you! We don't have Arnold installed anymore on H18 but that's interesting. There is a texture path parameter on the render settings that you can set to $HIP for example. It allows you to store textures relative to that. So you can store an image path as just "image.jpg". However this only allows for different usds be all relative to one location during render time. Absolutely not what we would need for a usd specific workflow where files are relative to their .usd files.

One issue we have seen (and had to fix for some of our own VOP nodes) is that file path parameters would be translated into USD string attributes, rther than USD asset path attributes. Only USD data explicitly marked as an asset path will get run through the output processors which convert full paths into relative paths. This is something that the Arnold developers would need to fix in their node definitions. Assuming this is actually the problem. I don't have Arnold installed so I can't test it myself ATM.

mtucker
I don't have Arnold installed so I can't test it myself ATM

Confirmed that the arnold::imagenode appears to have sidefx::shader_parmtypeset to 'string'.

Thank you so much for looking into this! I will send this to Arnold and hopefully they can fix it.