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Riccardo
12-12-2006, 05:54 PM
Hi there!

I was trying to find info about rendering maya hair in mental ray, so i came up with some clues:

--MR hair primitives; what are them? are they visible or somehow connectible to some mr shader in maya?

--MuhHair; How can i apply this mr shader to the fiber of maya's hairsystems? Do I need some other plugin or script? Has anyone ever succeeded using this shader???

--GG_GEO_PFXHAIR shader; same as above, has anyone succeeded using this geometry shader? Can anyone definitely explain its usage? any EXPLICIT step by step guide?

--Speed; hair in mental ray are at least 4 times longer to render in MR compared to maya software pfx. Is it worthy to use mr shaders with hair in terms of rendertimes?

Lamster
12-13-2006, 03:28 AM
to Attach muhHair to replace the maya hair, you could use ctrl_fur. You can download ctrl_fur from this forum, just do a search for it. Remember to read the thread for better instructions.

First thing you'd have to do is to create a small cube and also create and apply your muhHair as the shader for the cube.

Then you create a ctrl_fur node and assign it as a geometry shader to the cube.

Then on the ctrl_fur node, you type in the name of your fur feedback node eg. polySurface1_furFeedback into the object attribute, and you type the name of the shading group node eg. muhHair1SG into the shading engine attribute.

And that should make it work.

Terence

Riccardo
12-13-2006, 09:46 AM
I found Ctrl_fur last night, but I didn't succeded to make it work. Anyway I fear that it could be used with fur only, and not with hair.

Any suggestions?

MaNdRaK18
12-13-2006, 10:58 AM
... Anyway I fear that it could be used with fur only, and not with hair.


Fear confirmed. I tried the same thing, and it didn't work. Would be actually great if ctrl_Studio makes ctrl_fur work with maya hair too.

Riccardo
12-14-2006, 08:14 PM
I just did it!!!:twisted:

Actually it is possible to attach any mr shader to maya's pfx hair with ctrl_fur!!!
Just write down the name of the pfxhair instead of a fur description. Take care not ot use any upper case letter in the names or the render will fail.

My last question is: With this technique, can we find any other shading method to render hair in MR faster??? Does the ctrl_fur geometry shader REALLY use the MR hair primitives????

Riccardo

Riccardo
12-17-2006, 11:38 AM
I just found that maya fur can be rendered in volume mode ( faster). I wonder if it would be possible even with hair. I tried applying a volume shader to the hair, but only the hair shadows are rendered. Any ideas?

MaNdRaK18
12-19-2006, 10:54 PM
I just did it!!!:twisted:
Actually it is possible to attach any mr shader to maya's pfx hair with ctrl_fur!!!

OMG, it really works.

Riccardo
12-25-2006, 09:50 AM
I have real big problems in rendering maya hair with MR, since there's a lot of data and my 2Gbs of RAM are not sufficient. After a long research among MR forums I found that hair primitives are not geometry. They are special curves whose degree can be increased, so you could actually use linear fibers in the pfx (zero subsegments) and then tell MR to use its hair primitives at degree 2 or 3, translating less data therefore using less hardware resources. Unfortunately this is possible only during the translation or by writing a specific command in a geometry shader. At the moment there's no free geoshader which allows to do that.

Francesca.. where are you???

I thought i could be possible also via mrliquid, but it is for Maya 7 only at the moment.

strange_quark
03-15-2007, 12:21 AM
I just did it!!!:twisted:

Actually it is possible to attach any mr shader to maya's pfx hair with ctrl_fur!!!
Just write down the name of the pfxhair instead of a fur description. Take care not ot use any upper case letter in the names or the render will fail.

My last question is: With this technique, can we find any other shading method to render hair in MR faster??? Does the ctrl_fur geometry shader REALLY use the MR hair primitives????

Riccardo

are u sure this works? can u upload a scene. Whatever i try to do, it either renders with the hair missing or whith it just using the regular maya hair shader...

using maya 7.0.1...

thanks for any help...

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