Here’s an osl texture based on the paper “Artist friendly metallic fresnel” by Ole Gulbrandsen http://jcgt.org/published/0003/04/03/ Usage is: diffuse black, fresnel off, add VRayOSLTex to the reflection map. Example scene from vray-materials.de OSL texture [AFMFresnelgold.jpg] [ArtistFriendl…

The drop-down is actually pretty much done now and will be in the next SP. Best regards, Vlado

Hmm.. where do you see the rgb values for N and K on the refactiveindex.info website ? I only see the N and K, but not the rgb values ?

You need to change the wavelength to the appropriate value - R=0.650 G=0.510 B=0.475

Here’s mine for what it’s worth. :slight_smile: This is a somewhat different approach, I think I got the equation from the old Odforce Wiki. If someone wants to do complex number calculations in OSL there are a few functions for that included here. complex_fresnel_v001_rh.zip (829 Bytes)

This works like a charm, thanks guys! Vlado, would it be possible to include colour swatches next to the n and k values? It would be awesome if we can put the correct numbers in and then tweak the colours individually. It would give more control over a colour correct and keep the shader a bit simpl…

[image] Dynamic Memory too low error, VRAY Stops rendering Here is a shader that allows you to enter n and k values directly (for 0.65, 0.55 and 0.45 micrometers - you can get values directly from http://refractiveindex.info/ ) Use as a reflection color map and make sure the Fresnel option in the…

[image] Dental Office Vlado, that’s working great! But it seems I have to apply gamma to the osl texture, otherwise the result is very washed out. Really, that’s odd. It seems to work fine for me… can you show me? I have a feeling that applying gamma to this shader is wrong. Best regards, Vl…

Sure! Here you can see your complex fresnel osl with the values for copper. On the left without any modifications, on the right with gamma 2.2. When I redraw the reflectance curves with a falloff map, I get a result close to the gamma 2.2 version. Will check my gamma settings just to be sure, but I …

Ok; not sure about that one though - I just copied the formulas and I’m pretty sure the Fresnel equations do not feature any gamma correction. What are the n and k values that you used? I think the default ones that I put in the shader are for copper. Best regards, Vlado

My 3dsmax design 2011 crashes instantly everytime I try to load these OSL files; just to confirm it, can anyone doublecheck with an old max release?

Complex fresnel using VRayOSLtex

V-Ray V-Ray for 3ds Max V-Ray for 3ds Max :: General

kosso_olli February 19, 2015, 11:15am 34

Vlado, that’s working great! But it seems I have to apply gamma to the osl texture, otherwise the result is very washed out.

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Complex fresnel using VRayOSLtex

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