View Full Version : Optimizing render times with Polyplane hair with transparency?

06 June 2012, 12:39 AM
My character has about 30-40 planes with the same 2 hair textures at 1024 resolution. One being a normal map and the other holding the spec and alpha on the R and G channels. IS there any methods to optimizing the render time in this situation?

06 June 2012, 05:48 PM
try turning off filtering of the opacity texture maps.

Tim J

06 June 2012, 04:49 AM
1k texture for hair seems excessive. What aspect ratio are you rendering and close will you see it in camera?

Aside from that, optimize your max trace depth and use simple shadow method.

06 June 2012, 02:21 AM
What material are you using?

If you use the mia_material you can use the cutout opacity in the Advanced properties. This effectively ignores transparent areas of your object for rendering. It takes a scalar (grey scale) image.

06 June 2012, 03:34 AM
Hey bitter I came back to this thread to post my experiments with AO and trying out mia material x.

I was looking up tutorials on AO because I was having AO dark blob problems on my characters hair with a transparency map. I eventually found an old thread on here about how we are suppose to use mia materials for mental ray and all those other shaders such as blinn and phong for maya software.

So I switched to mia material x and messed around with the settings, applied my transparency to the hair shader and another AO enabled mia material for everything else.

The render is a hell of a lot faster now. the hair section of the render chugs a little still but significantly less than before.

I am very new to the mia material settings for good AO results so if you or anyone could forward me any links about AO with mia material that would be great.

I am surprised that my school has not taught us to use all the mia materials exclusively with mental ray.


Ok while typing this I just did a 9 minute render of my character with AO mia material with FG on. (36 second render without FG)

It appears that lights and shadows appear with the AO from mia material x. I am going to turn off the lights and see if I get the regular AO effect.

06 June 2012, 03:45 AM
Well without lights on the mia material x with AO on makes a good alpha map for my character ;\

EDIT: woops! setting ambient light to white fixed it... I think, the hair is looking a little weird now.

EDIT2: ok back to square one. Looks like I require a light in my scene to get proper AO on my characters hair. Without ligths I get the same dark blob shadow problem. AO shadows ignore the transparency when there is no light.

06 June 2012, 04:06 AM
I am surprised that my school has not taught us to use all the mia materials exclusively with mental ray.

Because a lot of places are horribly behind, especially a lot of schools where they aren't paid to stay current. Then I get students as employees trying to cram Blinn into a complex scene.

Or they download Vray and think "Wow, the arch material is great." Well yes, modern tools are great. . .

setting ambient light to white fixed it

Oh God, please don't use an ambient light for anything ever.

Do you have an image? What are the render times like based on the image? What do the render statistics say? (Switch it to Progress messages)

What version of Maya? And do you need AO on everything? Possibly not if you don't use an ambient light.

06 June 2012, 04:30 AM
maya 2011 64bit.

my apologies, i am tired and i thought ambient light when I meant to say was "additional color" from the mia material.

This is for my character reel and I wanted to put in an AO pass.

06 June 2012, 10:42 PM
holy crap I must have been delusional last night.

I did mean ambient light as in "ambient light color" which I set to white and it produced AO for me but the AO was giving the same problems as the previous AO setup I had.

So now after more research it looks like AO is suppose to be used with lights and final gather to get proper realistic AO.

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06 June 2012, 10:42 PM
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