Mental Ray - Shaders


#4661

Hi guys, I downloaded Daniel Rind’s diffraction shader, and it works great, except I can’t get it to reflect the environment. I apply the shader into mental ray material surface slot, but how to add reflectivity?


#4662

Use a blend material with diffraction on the base and an A&D with reflection in top, blend it with a falloff map.


#4663

Thank you, I will try that.


#4664

Hello everyone, How do I use normal maps with mental ray? I use normal bump and put my map into normal slot, but it renders as simple bump, like if you just desaturate your normal map and make it black and white. And when I use vray or scanline everything is fine.


#4665

I ran into this problem too only a few days ago and couldn’t find any answer online apart from “Mental Ray can’t…”. If it can, please tell us! :slight_smile:


#4666

With a quick test I see no problems with the normal maps in mental ray. I get the same result from both VRay and mental ray:

Using this map I found on a google search for normal map:
http://www.psionic3d.co.uk/gallery/displayimage.php?album=3&pos=4

That being said, if your gamma isn’t setup correctly and you load the normal map with the wrong gamma setting I’m sure you’ll run into some problems like this:
http://www.3dallusions.com/forums/44117-post15.html


#4667

Hmmm I definitely can’t seem to get it to work, but I’m still on Max 2008 - perhaps support was added in later versions?


#4668

I made a test with teapot and everything works, strange that it didn’t work before, looks like it was something wrong with gamma.

left - real teapot, right - normal map


#4669

Transparent water…i’ve got to be missing something simple here, but i have no idea what.

I have a box, about 12’ x 2’ x 4". Objects may have been touching it’s sides perfectly (coplanar faces), but i’ve since deleted everything but an xref’d site (30’ below it) and stuck a teapot a couple inches under the bottom face. Nothing I do allows me to see throw the water. My best guess is that the reflection is too strong, but lowering it makes the box darker. I’ve upped the samples in the refaction section to like 200. I’ve adjusted the 0 and 90 deg reflection values, used IOR, etc, and i’ve set it to thin wall and solid in the advanced section, and the material comes out solid no matter what.

This happens whether i use a standard AD and adjust the parameters myself, use the water preset (which says it has no transparency I know) and adjust it. Surely seeing through the water just a bit can’t be that hard of thing to achieve.

What is it that i’m missing?

FWIW, the xref scene has a daylight system in it set to MR Sun and MR Sky and the current scene is using MR Physical Sky as the env map…


#4670

You could check some of the A&D water sample scenes that are on the second DVD to help track down the problem with your scene/settings.


#4671

Thanks Jeff…turns out, that’s what you get for rendering an image the size of your screen. I hadn’t messed with water or anything transparent in months, so no need for refraction. Turns out the refraction depth was set to 0. I got tired of waiting and set the reslution lower for a faster render, and voila, the big ‘0’ sticking out like a sore thumb on the bottom of that tab under the render window. Real homer simpson ‘Doh!’ moment there. :slight_smile:

I knew as soon as posted the answer would be something easy i missed. Just had to go public with it to look to get to that facepalm moment I guess :slight_smile:


#4672

Hey guys,
Anyone able to help me out create some nice Procedural rock texture ?
Posted here, scene file also.
http://forums.cgsociety.org/showthread.php?f=6&t=832126


#4673

For skin i wanted to add SSS fast skin + displacement, because of the displacement, but for some reason It doesn’t work. I tried both Extrude map, and direction map and tried to pump up the strength but I get no effect no matter what. Please help me with a tutorial or an explanation. Do I have to modify some settings in rendering? or do I need to do something else? :bounce: :bounce: :bounce:


#4674

Also can anyone tell me how do I get the right “Scale Conversion Factor” for my sss skin? :banghead: :banghead: :banghead:

It would be nice if someone would upload their skin material :slight_smile: But I guess I wouldn’t take it cause it wouldn’t feel like my work to use it…


#4675

Comar93 - Check out my thread here aboutdisplacement

Also wouldnt worry about scale conversion factor, focus on tweaking your other settings first.


#4676

Thanks. :thumbsup:


#4677

I have a bunch of materials created in gamma 1.0 and now i’m working in 2.2.
Is there an easy way to convert the values?
Maybe scripting, a plugin, mathematical formula, magical potion… anything?
All my colors and reflections are inaccurate and it’s looking to be such a pain to fix everything.


#4678

Hello guys, i have a question here :

Is it possible to use the raytrace “exclude/include” reflection option (like using it on lights) on the A&D material ? i know it might be some advanced shader stuff involved …but i hope someone knows the answer
-to better understand for what i’m trying to use this - i have a lightplane that i want to be reflected only by one object in my scene .

  • using a light doesn’t even get close to looking as good as the lightplane option;
  • changing my materials to raytrace isnt one of my options -because of its disadvantages vs A&d mat(except for local reflection control , LOL ) ;

The materials i use don’t have the include/exclude reflection option(like the raytrace) -they are A&D shaders;so i thought there might me a way to implement that into MR arch viz shader


#4679

I think mr Raytype Switcher does what you want.

It’s hidden and you can enable it. Jeff Patton explains how to do it here: http://jeffpatton.cgsociety.org/blog/archive/2008/1/
(but his post is about color bleed)

Put black 0,0,0 in reflection and you’re set, if I understood what you really wanted.


#4680

i’ve tried it ,thanks for point ,but doesn’t seem do help :frowning: -can’t control the reflection assigning the switcher to diffuse slot- just its color ;or maybe it can help in a way,but i cant see how;
-to be more clear:
basically i want to exclude all objects from scene but one, from receiving reflections from one bouncecard (a self-illuminating plane)-wich i have more in the scene.-just like having a light instead of the lightplane and use the include option , select one object in the scene -so it will be the only one receiving light&shadow from that light -just that here im concerned about reflections -i could do that if i was using the raytrace shader,but thats doesn’t work for me -as i said in my previous post .can’t be more clear than that -if you still don’t get what i mean ill post an image too.
if anyone has any idea ,ill be very happy to listen it :stuck_out_tongue:
cheers and thanks again for the suggestion