I see, what is the proper way to create these materials. I guess there should be some automatic way or something, right? I cannot imagine that this has to be done manually.
Imagine that I have hundreds of such rooms. There should be a way to automatize this procedure.
I’ve found this thread where a similar discussion was up. According to @Terrance_McMinn1 I could create my materials by porting them from the .mtl files but what it is not clear to me how the r, g and b can be extracted from the variables Ka, Kd and Ks since each one of them has their own correspondences. Is it fine to use only the values from Ka. Also how do I define the values of specularity and roughness.