Reflections
Reflection functions
I have been experimenting with BRDFs lately.
In the picture above, from left to right: Oren Nayar, Torrance-Sparrow with different roughness, and smooth dielectrics.
Reflection functions
I have been experimenting with BRDFs lately.
In the picture above, from left to right: Oren Nayar, Torrance-Sparrow with different roughness, and smooth dielectrics.
I think Oren Nayar is very similar to a Lambertian BRDF ,as a matter of fact I see no difference.What type of material can you model with this BRDF that you can’t with a Lambertian BRDF ?
As for other 4 spheres , it looks to me like the modified Phong BRDF width different roughness.
Anyway ,I like this render .Great Job!
@D-POWER
Oren Nayar takes into account the microfacets distribution and effects like shadowing and interreflections. But as the microfacets are Lambertian, the model does converge to a Lambertian BRDF when the variance parameter tends to 0.
In the render above I used the Blinn distribution function, and a pretty high Ior. So obviously your observation has some truth in it.
(The right-most sphere is pure Fresnel reflection btw.)