Method for creating grass?

[andyH]

Hello all, I have been trying to decide what is the best method for creating realistic looking grass in 3dsmax 2010 with mental ray.

 

I am new to 3d and max, but I know enough to realize that grass would have the potential to push the poly-count very high and significantly increase render times.

 

I want a low shot so that the foreground shows realistic grass so this would require geometry, but I dont know how best to create the scene in the most economical way, any insight on favoured techniques would be appreciated.

 

EDIT: I would also like to include other grass-native plants such as small daisys etc as the scene needs a portion of the lawn to be a little wild and over grown.

Edited July 27, 2009 by andyH

[Joel Gray]

Try the tutorials half way down the page here --> LINK

[andyH]

Joel that's great, thanks. But it looks like the tutorial is specific to Vray, and I am using Mental Ray. I will take a look and see if the process can be applied to Mental Ray.

[Joel Gray]

It can, I use both Vray and Mental Ray. You can get the same effect with the materials in Mental Ray - fake SSS with two sided materials and transparency. Mental Ray in Max 2010 also has Displacement just as Vray. The modeling aspect is the same no matter what render yo use.

[andyH]

Thanks for that Joel, I will have a crack at it. I am very new to 3d andI will have a go, but I suspect I will run into trouble with faking the SSS and figuring out what displacement means when related to a renderer. My only knowledge of displacement is the use of displacement maps on materials and I have also seen but never used the displacement modifier, is that the same thing you are refering too?

 

If you have time I would really appreciate a quick and dirty step-by-step, just to keep me out of trouble .

[Joel Gray]

Look up displacement mapping in the Max Help file, that should get you started in the right direction. But for your application, I would suggest using geometry. Faking SSS means to simpligy Sub Surface Scattering, the affect of light scatter as it penetrates the surface of the grass. That can be achieved by using a 2 sided material and opacity. Have a look at the link I sent, there's a lot of useful info there that you can study and reference.

 

Others here may have better suggestions and tutorials for you... Grass and Trees are always asked about because they are the most difficult to achieve good results.

[andyH]

OK Thanks Joel. For anyone else thats interested I found this tutorial that may be useful.

 

http://www.jeffpatton.net/MR_Grass_Displacement.htm

[TheAllusionisst]

Jeff also goes over a bit at MrM and links to a discussion at VD here:

 

http://www.mrmaterials.com/jeffs-blog/101-mrproxy-grass.html

[jinsley]

check this out also... good technique not specific to leaves and I find it renders quite well... especially when used in conjunction with proxies.

 

http://3dsmaxrendering.blogspot.com/2008/06/translucent-leaves.html