genBSDF for Rhino obj file


I am trying to run genBSDF to create a .xml for shade fabric materials.

I modelled a generic patch on rhino which i saved as a .obj file. Next, i used obj2rad to turn the obj file into a radiance file which i finally used for genBSDF using the command

C:\Radiance>genBSDF +f +b -c 500 -gom meter E:\BSDFW\BSDF.rad > E:\BSDFW\BSDF.xml

It gives me an error saying it cannot identify the object. Does anyone have a reference how i can achieve the same?

Error statement
oconv: fatal - (C:\Users\prana\AppData\Local\Temp\genBSDF.pusMSw\device.rad): undefined modifier “object_1”
Could not compile scene

Welcome, Pranay,

Thank you for including the error in your updated post – this is helpful to understanding your issue.

The output of Rhino does not carry the necessary material information that is needed to perform any kind of lighting simulation. This is fairly basic in Radiance, and I refer you to Chapter 1 of “Rendering with Radiance” for a general introduction.

Also, play close attention to the details in the genBSDF man page regarding the placement of geometry, which must be near to the X-Y plane but not in the positive-Z half-space.

Feel free to explore the Radiance documentation pages for more information.


Hello Greg,

Thank you! I shall go through this, i was able to assign a material to a .obj file to run genBSDF. Im not sure though if i got accurate results!