Multiple displacement maps in the same Vray Material?

Become a member of the CGSociety

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

THREAD CLOSED
 
Thread Tools Search this Thread Display Modes
  03 March 2013
Multiple displacement maps in the same Vray Material?

Hi.

So I have a quite complex question for you Maya Vray experts out there.

I have a glass bottle that I'm visualising and I'm looking for a more flexible way of applying several displacement maps to one Vray Material Group.
I know it's possible to apply f.ex several Vray Materials to the same model by using a Vray Blend Material and assign each Vray Material to it's own UV set. This is a great workflow if you f.ex wanna apply several labels to the bottle but still keep the glass material as a base. This also allows you to have each fileTexture assigned to it's own "Sub Material" , which is great when you want max resolution out of each map.

This looks as follows;
Filetexture ---> VrayMtl ---> VrayBlend
And each of the VrayMtl are assigned to it's own UV set.



But I've never managed to assign several displacement maps to the same VrayShader. Using the same technique as described above simply won't work as the default DisplacementShader in Maya works on textures and not materials (so using the VrayBlend wont work). I have tried to feed several FileTextures into a LayeredTexture shader and then feed that output into the DisplacementShader and that makes both displacement maps show up on the geo, but I can't assign them to their own UV sets as they don't show up in the Relationship Editor. So that's also a dead end...



So my question is:
- Is this possible at all? (are there any Vray nodes that might help with this)
- If Yes; how do I connect the nodes up (please be specific).


.
 
  03 March 2013
you would do this with a plus/minus utility to add the displacement textures together:

http://www.can-con.ca/tumblrpics/displace_combine.png

you need to convert the RGB to luminance as well, because the displacement texture expects a scalar greyscale value.


The result:

http://www.can-con.ca/tumblrpics/multi_displace.jpg

The tricky part is controlling the offsets. You will probably need to set the colour value (brightness) to values over 1 for texture you want to get more prominence. And, unless you want it all to bloat outwards, you will want to lower your black below zero. The checker above is set to 20 for the white and -20 for the black. Here's the scene if you want it :

http://www.can-con.ca/tumblrpics/multi_displace.ma

Last edited by cgbeige : 03 March 2013 at 07:25 PM.
 
  03 March 2013
First of all, thanks for replying!

I've looked through the Maya file you sent me and it's a good way to combine/add two displacement on top of each other. Thanks for taking the time!
Although using a layeredTextureShader yields much the same result (but maybe with some less control...).

But the method you described does not take into account UV sets. What I want is to have several displacement maps assigned to it's own UV-set on the same geometry with the same Vray shader... (I might be asking for too much... )
 
  03 March 2013
It's easy to assign different UV sets to different textures but it gets a little weird when you combine them for a displacement. You can do it but, as far as I know, you have to assign the materials to a shader element (diffuse color, for example) on the mesh first so that you can change the UV assignment in the UV linking editor. See what I mean in this video:

https://vimeo.com/61141185

So connect the displacement textures to shader elements, assign the UVs to the respective texture in the UV linker and then disconnect them from the shader assignments but not the displacement network. The UV linking changes will stick.
 
  03 March 2013
Solved!

Yes that worked!
Thank you so much! (I love your blog by the way, I check it all the time!)

Ok, so for anyone else watching this post later on. Hook up each of the file-textures that contain your displacement to your displacement shader via a layeredTexture node. Then connect each file texture to one of the color slots("Diffuse Color", "Reflection Color" it really doesn't matter which) in the VrayMtl as well.

So now each file-texture should be connected both to your layeredTexture and your VrayMtl.

Go to your Relationship Editor and connect each file-texture to it's respective UV-set.
When your done just delete the connections from the file-texture to the VrayMtl. And you should be connected...

 
  03 March 2013
I made a blog entry that explains the whole process a little more clearly, just for posterity (hello, ant overlords):

http://polygonspixelsandpaint.tumbl...ost/44718627300
 
  03 March 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
CGSociety
Society of Digital Artists
www.cgsociety.org

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

All times are GMT. The time now is 02:41 PM.


Powered by vBulletin
Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.