Hi everyone!
I have implemented a torrance-sparrow BRDF shader and I'd like to know if a table or a rule of thumb exist to map the params of the model (F0, rho s, rhoughness) to real material.
Thank you!
Micheal
Real world material - Torrance-Sparrow BRDF Params
your google keywords are "brdf fitting".
in short: you scan real world materials, take those scanned BRDFs and try to approximate the scanned result by your analytical BRDF of choice. There are already some tools offering that (e.g. BRDF Lab), including pre-visualization, so you know whether your implementation works flawlessly in comparision and you can evaluate several BRDFs to find the one that fits your needs best.
in short: you scan real world materials, take those scanned BRDFs and try to approximate the scanned result by your analytical BRDF of choice. There are already some tools offering that (e.g. BRDF Lab), including pre-visualization, so you know whether your implementation works flawlessly in comparision and you can evaluate several BRDFs to find the one that fits your needs best.
Also, bear in mind there are plenty of materials for which fitting a Torrance-Sparrow won't give good results. For those difficult materials I almost always ended up approximating them with multiple isotropic or anisotropic gaussian lobes. Those have the advantage of analytical integration and convolution operations.
This topic is closed to new replies.
Advertisement
Popular Topics
Advertisement
