A while ago I wrote a blog post called ”Creating Mastering Vray style shaders in Maya”. My goal was to translate some of the techniques Grant Warwick uses in the course Mastering V-Ray in 3ds Max to Maya. A lot of people still contacts me about these techniques and I’ve been feeling more and more bad about how outdated they are. So I thought it was time to update this and show how I would create these shaders today. And with new features like GGX and OSL it’s both faster and simpler to do now!
This post will cover how to create a plastic and a gold shader. Basically what I do is recreate the shaders from Mastering V-Ray: Lesson 02 – Materials 101, but with an updated approach. If this is something that people will find interesting I might continue and cover other Mastering V-Ray lessons in Maya. So please comment or contact me and let me know what you think!
Let’s start with the plastic shader. This is how the node tree looked like with the old setup:
It requiered three different V-Ray materials (with different values for Reflection Glossiness) to be blended together. I’ve also used the RemapValue node as an equivalent to the Falloff node in 3ds Max which is not ideal since it is pretty clumsy. V-Ray 3.3 introduces a Falloff node in Maya with a lot of the same features as in 3ds Max. I’ve only tried it briefly but I was a little bit disappointed by the lack of bezier handles. For this plastic shader I didn’t need any falloff node since I could get the desired result with a simple V-Ray material with GGX as BRDF. Here is the settings I used:
Here is a comparision between the old shader (to the left) and the new (right):
And now on to the gold shader. I’ve used the same approach as with the plastic shader to not blend multiple materials but to rely on a single material with GGX as BRDF. The other big difference is that I use an OSL texture for the reflection instead of using Remap Value nodes. The OSL texture is called Complex Fresnel and you can read more about it here: http://docs.chaosgroup.com/display/OSLShaders/Complex+Fresnel+shader. The way I use this is that I start by browsing to the right material on http://refractiveindex.info/ and simply type in the right values for n and k based on the wavelength (0.650, 0.510, 0.475 for R, G and B). This is how the page looks like:
There is actually a shelf called ”selected data for 3D artists” and that’s a good place to start. However, I found the values for the gold there made it look to reddish, almost like copper. So I tried a few different other Pages and chose the values from the Babar and Weaver 2015 instead.
And this is how the OSL texture looks in Maya:
All of this is better explained here: http://viscorbel.com/vray-materials-part-3-metals/ so I encourage you to read that as well.
This is how the node tree looks like for the gold shader:
The color correction is for purely artistic reasons to tweak the shader to your own liking. In this setup I tried to make the gold look more like the old shader. This Color Correction node is not a default node but can be created from Create – V-Ray – Create from V-Ray plugin – Texture. By multiplying the reflection with a V-Ray Dirt I make the shader slightly less reflective in occluded areas.
This is the final settings for the shader:
And here is a comparision between the old shader (to the left) and the new (right):
As you can see they are not exactly identical but I think they new one is looking better so I didn’t tweak it further to match the old one. Also worth mentioning is the significant dropoff in render time between the old shader and the new.
I have some plans to continue with these blog posts and the next one up would be a Green Metallic Paint shader, which is similar to the one Grant creates in Mastering V-Ray: Lesson 04 – Advanced Material Creation Part 1. But like I said earlier, it depends if someone actually finds this interesting. So please comment and let me know what you think and what you would like to see in the future.
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