VRay Material converter

[arya_gupta]

Hello,
I have a workflow that includes downloading many OBJ files with their mtl files from OnShape, and importing those geometries into Cinema4d to render with VRay.
I understand that those materials, when imported with the obj file, cannot be read by VRay as it renders it black. From what i understand VRay has its own material type, and has a tool to convert other materials to VRay materials, in VRay-Tools-Convert Materials. However doing this only gives me empty materials.

I have even loaded textures and then converted material, yet nothing happens.

Is there any way to deal with this? Since these files from onshape are those of certain machines, and have many many (hundreds) materials assigned to them. So doing it manually would be a big waste of time.

Thank you in advance for helping

[deyan.hadzhiev]

Hi arya_gupta - the material converter in V-Ray currently always converts the materials to Node Materials. The Node Materials in Cinema 4D may contain multiple node spaces and their previews are rendered with the currently active node space. Put simply - in order to see the material preview you must select V-Ray as your current renderer (in the Render Settings), or alternatively, you can just switch to the V-Ray Node Space (from the menu: Render -> Node Spaces -> V-Ray).

Note that even if you do not change the node space, the materials should render fine, as long as the conversion was completed without errors.

Please also note that the converted materials may not always render the same as the Cinema 4D materials.

I hope this solves your problem.

[arya_gupta]

Hey deyan.hadzhiev - Thank you for your prompt reply!
I made sure the current renderer was VRay, and the current node space was Vray too, along with loading textures. This time all the materials became black, and they render black too. Any idea why that may be happening?

[deyan.hadzhiev]

Now this seems more like a problem with the conversion itself. Can you attach a small example scene with the original materials so we may investigate why the materials might not convert as expected?

[arya_gupta]

deyan.hadzhiev Attached is the zip file of the scene

[deyan.hadzhiev]

After investigating the materials - it seems they all have a transparency layer, which the material conversion considers as refraction (with black fog / absorption color). This is something we will improve in the future (I logged an internal bug report for this: VC4D-1986).

In the meantime, to workaround this problem, you can select all the imported materials and manually disable their transparency layer from the Basic tab (example below)


Sorry for the caused inconvenience, and I hope this solves your problem until we fix this in the converter.

[arya_gupta]

Hey deyan.hadzhiev Thank you for your response and the solution.