fresnel reflection, with a reflection map

Become a member of the CGSociety

Connect, Share, and Learn with our Large Growing CG Art Community. It's Free!

Thread Tools Search this Thread Display Modes
  11 November 2013
fresnel reflection, with a reflection map

Does anyone know how i can make a fresnel reflection while also using a reflection map?
I know the method of using the ramp and samplerinfo connecton to achieve this, but i cant figure out how to do it while also uing a reflection map to mask the variations of intensity.

I read and tried to use the ramp and samplerinfo node together with a multiply divide node. I connect the ramp and reflection map into the multiply divide node, then connect multiply divide into reflection of the main shader.

I dont know if i connected them right, or if this method works at all..

Can someone help me?
  11 November 2013
If you use V-ray or Mental Ray materials, you can simply enable Fresnel in the material itself and you'll get the same effect without having to connect anything.

If you want to use ramp, plug the ramp into the "Amount" slot. The "Amount" slot works the same as multiply/divide.

For Vray, every color attribute will have an accompanying "amount".
For example. diffuse color & diffuse amount, reflection color & reflection amount, etc.
I believe it's the same for MR too.
  11 November 2013
thanks for that answer, i will try. But im not sure what you mean by the amount slot??
  11 November 2013
Did a quick check and the wording is slightly different on each renderer.

Mental Ray
Diffuse Color & Diffuse Weight
Reflection Color & Reflectivity.

Vray uses "Amount"

Redshift uses "Weight"
  11 November 2013
thanks, i tried around with this but i couldnt really make it work. Maybe i had some wrong settings, i dont know. However, i connected both the ramp and reflection map to a layered texture and then this to the reflection slot. It seems to work. Just need to find out if its accurate...
  11 November 2013
If the ramp is for fresnel, you don't need that. There's a proper physical one built into the shader. (assuming MR here, since you said "reflectivity"): Attach your reflection map to reflectivity (make sure "alpha is luminance" is on in your texture) then under the BRDF rollout, enable "use fresnel reflection".
  11 November 2013
Thread automatically closed

This thread has been automatically closed as it remained inactive for 12 months. If you wish to continue the discussion, please create a new thread in the appropriate forum.
CGTalk Policy/Legalities
Note that as CGTalk Members, you agree to the terms and conditions of using this website.
Thread Closed share thread

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Society of Digital Artists

Powered by vBulletin
Copyright 2000 - 2006,
Jelsoft Enterprises Ltd.
Minimize Ads
Forum Jump

All times are GMT. The time now is 09:27 PM.

Powered by vBulletin
Copyright ©2000 - 2018, Jelsoft Enterprises Ltd.