Using Vray fur to create grass in 3ds max scene

[Val the Sinarb]

Hi!
I have not worked with V-ray and 3ds max for a while, now I have the newest version and I am trying to grasp it and experiment a bit.
I am now preparing a scene for my visualization and I would like to have a nice looking grass in my scene. I decided to use V-ray fur to do the job.
I have followed this old tutorial https://archvizcamp.com/grass-vray-fur-modifier/
Of course, things have changed since, so for example "flat normals" dissapeared and I have to use the V-ray hair material instead. I did not find any detailed tutorial how to do that, so I have just took the basic V-ray hair material, changed color of the hair and add my grass texture. As you can see, the result is not at all as in the image from the tutorial.
This would be my first question:

How to correctly use Vray hair material to map the fur / grass?

Secondly, I have a lot of green / grass areas in my scene. But if I try to use Vray fur on all of them (actually even more than just the one you see in my image or if I try use higher distribution of the grass), my render crashes due to "out of memory while building Embree tree"
I have 32GB of RAM and I can indeed watch in my performance manager how 3ds max use it to the max and then crashes.
And there is my second question:

How to use Vray fur on large surface without the render crashing? Would it help to use the fur as proxy? If so, how to that? I have exported the fur as vray mesh, but when I import it then, I do not see it in the scene / render.

Thank you for any advice.

[PIXELBOX_SRO]

Hi Val,
using vray fur for this is TOTALLY inappropriate. Sorry for being sincere.
Fur is just not optimized to cover large areas as this - hence memory problems.
And also, its impossible to map the strands :-/

Use Forest pack or a different scatter tool for this.
M

[rikou]

agree with Martin, you have to find a compromise and deal with Lvl of detail / Start distance / Rate if you want to cover a large area, it's really depends of your scene....
Anyway, it's really fun to play with vrayfur !!

[vjaramillo]

I second that. It's best to use a scattering tool like forest Pack which has optimized grass presets which render fast and look great. Fur is more for rugs, furniture, or other smaller areas.

[voltron7]

I've tried it, and sometimes it works out, and yes, uses all the ram, but not crashing (usually )
The most efficient 3D ways, I also agree, are with Multi-Scatter and FPP, but I find MS is easier to get nice boundary edges...

Here is a WIP using VrayFur...Scene also is quite heavy with other ForestPacks. It's not complete and the materials needs work, but, it was fun to try it...my machine has 32GB and is a 6 year old BOXX.

The one big advantage I find is the grass always stays where it is supposed to be growing!

[squintnic]

I think Forest will make a much better solution here and look 1000% better, even using the out of the box presets. have you looked at the edge modes to control where it grows?

[voltron7]

Yeah, FPP edge modes can help make the border better, but lately I find Multi-Scatter needs much less fiddling (basically none) to get nice border results...but anyway, the OP was asking about How to use VrayFur for grass, so I was trying to respond regarding the use of VrayFur for Grass...Countless debates exist on which to use, right?

[fixeighted]

I remember many hours/days wasted years ago trying to achieve anything useable with fur grass, so never going to advise that route.

To add another solution with Forest Pack; because I got annoyed with it not accepting edge mode on GPU, I decide quite often to use around 6 different single/double blades of grass and scatter those instead. No edge issues!
You can offset colour using the maps and you can also achieve a more realistic result by unlocking the rotation x/y coords and randomising those too. It will look pretty much like that in your image.