View Full Version : New Arch & Design material (Mental Ray)

10 October 2006, 08:47 AM
Hi :)

I've been playing with the new Arch & Design material in Mental Ray and it's really awesome, easy to use and it renders fast, I love it.

My only concern is (and yes I did read the help file and followed the tutorial ;)) the fact it doesn't seems to be possible to control either the Reflection of the Refraction with a map (I know you can control the glossiness with a map and I'm aware of the Cutout map to punch holes). So I was wondering how to use a specular map and / or have various level of opacity on an object (not controlled by the thickness of the object).

Are you aware of a solution, did I miss something ?

Thank you for your help :)


10 October 2006, 01:07 PM
It's controlled through the color swatches. You put a greyscale map into the reflect or refract color swatch.
Black = no reflections
White = reflective
Grey areas = varying

Black = solid
White = transparent
Grey areas = varying

What is probably throwing you off is that the reflectivity & transparancy amounts 0 to 1.0 still function even though you have applied a black and white map to the color slots. So if you have the reflection or refraction amount set to 0.0, then neither will work even if you have a black & white map in the color slot.

10 October 2006, 01:59 PM
Thank you very much Jeff, I must admit I had totally overseen this :D It was the only negative point in the arch material for me and thanks to your help I will be able to push my playing further :)
Btw, I saw your other post about the Arch Material library and i find it to be a really great idea, I hope that despite my "noobness" and my bad English I will be able to help and learn through it :)

Have a great week end.


10 October 2006, 01:29 PM
Jeff is spot on... the "reflectivity" spinner is really just a linear scalign to the reflectivity *color*... which you can map. Same for transparency.

The mapping was only added to the color for performance reasons, since it would have been somewhat redundant to allow it on the "level knobs" as well.... any end-result can be acheived either way.

I'm curious, how do you like the docs on the mtl?

I spent some long nights writing most of that ;)


10 October 2006, 01:52 PM
Håkan, firt thank you for you hard work :) The help file for the mental ray A&D material is indeed excellent and easy to understand with plenty of exemples and the quantity of images really help grasping what setting does what (the tip and tricks part is also a big :thumbsup: )
The only problem I had with it, was finding those two parameters (I'm probably guilty there, experimenting more would have been good I guess), everything else was crystal clear.
I suppose, I got disapointed too fast thinking "Damn, this material is extremly cool but will only be suited to archviz and design and it won't be possible to make them dirty :(" (I've nothing against archviz and design, btw, I have seen extremly beautiful images).
I never really considered Mental Ray before, seemed way too complicated (and slow) for the little guy but now everything is changed.
I hope some day, all Mental Ray shaders will have the same kind of documentation (or that someone write a book which would soon become a best seller ;) ) so it's possible to use the full range of possibilites.


10 October 2006, 02:22 PM
There are myriad ways to make them dirty.

Note for example that the energy conservation feature diminishes the total amplitude of the specular lobe as the glossiness is "widened" (to preserve the total energy(=area) under the lobe)... this means that if you simply map some noise to the 'glosiness' parameter it will actually vary both in a physically plausible way, so it will really look like a surface with varying glossiness, without you having to modulate both the intensity and spread.... try it with fingerprints, dirt, dust, spilled milk, whatnot....

Also, nobody is stopping you from putting the A&D material into a "Blend" material and mix with something else.... or a different setting of itself.

I did a pretty cool "dirty car" rendering ( that way....

Don't be fooled by the "name" of the material that it's only for arch-viz.... sure, it has an "aim" for that particular set of rendering problems... but you could just as well call it "The General Purpouse Material". We couldn't call it the "mental ray" material coz, well, there is already one. ;)


10 October 2006, 10:04 AM
Thank you for the tip MasterZap, I tried and yes, indeed, you can get great worn looking materials that way :)


10 October 2006, 11:48 AM
to Master ZapDocs on new arc-design mtl are great

04 April 2007, 08:58 AM
I have to add myself to that. The one thing we really need, besides good software, is good help docs. And the A&D ones are REALLY good! Lots of gratitude, MasterZap!

P.S.: I would also like to express gratitude towards the one that wrote the MR lighting tut in max 9 - it is the best one I've seen yet, explained EVERYTHING and brought me into the light :D

04 April 2007, 05:32 PM
I'll let him know. And no, it wasn't me, although I offered some input and proofread it ;)


04 April 2007, 05:58 PM
And no, it wasn't me, although I offered some input and proofread itAre you serious!? Crap, I've been telling people it was from you. Well, my apologies to whomever wrote it.

04 April 2007, 06:44 PM
Are you serious!? Crap, I've been telling people it was from you. Well, my apologies to whomever wrote it.

The A&D Docs I wrote, but the interior tutorial I didn't actually type, no. At least not all of it. I was an influence on it, and some paragraphs are mine but most of it, no.


04 April 2007, 01:46 AM
MasterZap, I'm looking forward to your next blog posting, and I'm also curious about what you suggested with SSS and A&D reflection mapping. I'v played around with it, but I'm wondering where you were going with it.

Keep up the good work.

04 April 2007, 07:30 AM
I second that, I check your blog regularly (and Jeff's) and updates are always very interesting. Thank you very much again :)


04 April 2007, 08:11 AM
Yeah, I'm hooked on Zap's RSS feed too :D

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