vray displacement grass

V-Ray V-Ray for 3ds Max Issues
1

I love the vray displacement when used for grass or groundcover areas but…
I have a drive thru down a residential street where the lawns have vray displacement on them and as the camera moves along the street some lawn areas will suddenly change or snap from one shade of lightness to a lighter shade. If the change was gradual it would not be noticeable but the change “Pops” as the camera move along. I’m guessing other people have run into this and i was wondering what they did to get rid of it. There is no GI, the lighting is not moving, just the camera. I’m using Max camera and the lighting is a Direct target light as the sun. I’m thinking it might be a displacement setting but hoping that i don’t need to increase the quality and thus slow down the rendering time.

Any ideas?
mh

2

What kind of displacement are you using (2d or 3d)? What is the displacement map? Also, can you show two frames with different lightness on the grass?

Best regards,
Vlado

3

I’m using 3d mapping. The displacement map is a desaturated version of the grass map with the contrast turned up. I have no idea how one gets images up on the forum. The FAQs don’t address it (at least i didn’t see anything there)
mh

4

Looks like a triangulation problem. Images / Wire ?

Best regads,
nikki Candelero

5

Nikki,
I have no idea what “images/wire” means. I’m running a 30 frame animation test on it right now with view dependent turned off to see if that makes a difference.
mh

6

Sorry for misunderstanding.
I meant - show some rendered images, and wire-screen shots of the grass objects.

Best regards,
nikki Candelero

7

Hi Nikki,
Like i said in one of the posts above, i do not know how to post an image to this forum and the FAQ didn’t help me. If you or someone else could direct me to something that explains how to add an image to a post it would be much appreciated.
mh

8

Please take a look at this thread:
http://www.chaosgroup.com/forum/phpBB2/viewtopic.php?t=12769

Best regards,
nikki Candelero

9

Thanks Nikki but signing up for yet another site is not my idea of a good thing, I get enough Spam without adding another source to it.

My turning off view dependent seems to have solved the problem..but creates another problem, i think, i need to render a longer sequence to be sure.
If i need to post images i’ll post at the autodesk max forum (the area) and link to that.
mh

10

well a picture is worth a thousand words as they say. But whatever floats your boat. :smile:

11

Its an image host site, they wont give out spam. And imageshack.us dont make you sign up, neither do xs.to, or paintedover.

It’ll probably be the view dependant 3d.

Can you not use 2d instead? Never usually gives problems.

12

Thanks for the direction to sites that don’t require signing up. I’ll check those out. Turning off view dependent was not the answer but it looks like turning down the “edge length” is going to work…i’ll know as soon as the sequence is done rendering.
mh

13

reducing “edge length” just reduced the effect…didn’t get rid of it. Switching to 2d mapping got rid of it…gives a bit of a different look but i can live with that.
mh