BRDF query

[eVisPer]

All,

I'd like to be able to report BRDF details of the materials I'm using as stimuli in a study. I seem to have read that the Octane Render glossy material BRDF is held as proprietary. Can I import a BRDF to use? For example, can I use a reflectance function from the MERL BRDF database?

Thanks,

eVisPer

[eVisPer]

At the heart of my query is an attempt to understand what is happening when I'm changing a parameter like 'roughness' in the Glossy material options. One possibility is that a single measured BRDF is fit to some model that allows you to modify relevant parameters to generate new analytical BRDF's. A super exciting way of doing it would be to measure a number of different materials, building up a space that varies across perceptually meaningful parameters, and interpolate in your space to create new BRDF's (see linked).

http://people.csail.mit.edu/wojciech/DDRM/ddrm.pdf

Can someone give me some direction as to which way Octane Render might work set up a 'new' material, given the input variables?

Thanks!

[matej]

Why dont you look at some opensource renderer, like Cycles, instead. I highly doubt you'll get such technical (& "sensitive") info here.

[mattrumba]

I can believe the internals are somewhat closed. However, it seems to me if Octane is indeed a 'physically based' renderer then it should be straight forward to get some info on how you're supposed to mimic real world properties, using typical real-world parameters.
I would also be interested in information on how to achieve physically correct material properties, be it using BRDF's or otherwise. It would be great to know what real-world parameters we are actually modifying when it comes to adjusting sliders with names like those in the glossy material.
Thanks for any pointers!

Matt

[eVisPer]

Yeah, I know that I'm querying the 'sensitive' bits of the software. But if I can establish some equivalencies with existing published BRDF models it would be inordinately useful for me and the community that I work in.

I like the software, it's intuitive, speedy and comes with a seasoned community of developers. I'd much rather try to figure this out than to try something inferior in these respects.

Thanks!