Isotropix Forums

Scattering small vegetation: grass fields, corn fields...

General Discussion about Isotropix and CG related topics

Scattering small vegetation: grass fields, corn fields...

Unread postby lookdev » Tue Feb 26, 2019 8:17 am

How would you go about scattering grass on a large surface, or in general scattering small vegetation, corn fields, flower fields ...?
I'm new and trying to fill a large space with grass, used a plane/grid as a zone in SpeedTree to populate with grass then scattered it in Clarisse, but as you see it is so repetitive. I've scattered 10 different exports from SpeedTree.
Would you scatter individual grass blades, or patches or larger segments of grass?
Any advice is much appreciated.
Attachments
grass scattering 10 different planes.JPG
grass scattering 10 different planes.JPG (54.35 KiB) Viewed 413 times
grass scattering interface.JPG
grass on plane speedtree.JPG
lookdev
 
Posts: 52
Joined: Sun Apr 30, 2017 1:08 pm

Re: Scattering small vegetation: grass fields, corn fields..

Unread postby ayanik » Tue Feb 26, 2019 10:19 am

Don't use rectangular patches, the seam will be very easy to see.

You can scatter scatterers.
Make some grass patches by scattering grass blades on a irregular shape(use translate x/z variation). Then scatter these grass patches again onto your terrain. It works best if you have several grass patches instead of one.
ayanik
 
Posts: 48
Joined: Wed Nov 26, 2014 9:10 pm

Re: Scattering small vegetation: grass fields, corn fields..

Unread postby mdkai » Tue Feb 26, 2019 10:43 am

Aside from that, great soccerfield :)
mdkai
 
Posts: 244
Joined: Tue Oct 07, 2014 7:24 pm

Re: Scattering small vegetation: grass fields, corn fields..

Unread postby isoyann » Tue Feb 26, 2019 4:08 pm

Random rotation of grass patches also works well to break the repetition.
User avatar
isoyann
 
Posts: 635
Joined: Mon Jan 28, 2013 11:11 am

Re: Scattering small vegetation: grass fields, corn fields..

Unread postby Akam » Tue Feb 26, 2019 4:37 pm

Nature is Chaos. No grassfield is made out of just a single plant, there are douzens of species, each in counterless variations.
Your setup tends to show a repetitive pattern not only because of the method you used but also because you scatter them on a totally flat plane. In nature hardly anything is so flat, not even in a park ( Soccerfield, Football yes, but I assume you don't want that, since you allready have that ;)
So in your shot you can hide a lot of these with clever placement of objects and a good terrain, a good ground texture setup also makes such seams less prominent.
My method:
I use several grass species in different scatters and use Clarisse procedurals to decimate the scatters to get a more chaotic distribution. I try to make clusters of plants since a lot of plants grow in clusters, also on a meadow.
Mimic nature is the key to realism.
Akam
 
Posts: 45
Joined: Thu Jan 11, 2018 6:39 pm

Re: Scattering small vegetation: grass fields, corn fields..

Unread postby esmith » Wed Feb 27, 2019 7:34 pm

How you scatter is up to you, the most efficient way is to use the fewest unique polygons. When i'm doing things like this, I would scatter points on the entire piece of geometry that I want to cover in grass. I would then simply scatter my grass objects, of which you have 10. It's super important on the scatterer, to use rotation variance, scale variance to get randomness.

Then you can use various methods to parse down the scatter system. Scopes, gradients...decimate points, etc. Particle Paint another scatter point cloud close to camera to use with more variants of scattered geometry. You could use a black and white texture, where the balance of black and white was generated via a blend driven by a Particle Paint and you could paint a variable that way, to vary the plants.

Here is a small setup, with 3 Speed Tree grass types, variants in the standard scatter settings, but you can also see some edges where I'm stamping down the grass with scopes,etc...

hope this helps.
AAaa.jpg
User avatar
esmith
 
Posts: 115
Joined: Mon May 22, 2017 4:11 pm

Re: Scattering small vegetation: grass fields, corn fields..

Unread postby lookdev » Sun Mar 10, 2019 6:27 am

Akam wrote:I use several grass species in different scatters and use Clarisse procedurals to decimate the scatters to get a more chaotic distribution.
Mimic nature is the key to realism.

Thank you. What do you mean by Clarisse procedurals?
lookdev
 
Posts: 52
Joined: Sun Apr 30, 2017 1:08 pm

Re: Scattering small vegetation: grass fields, corn fields..

Unread postby lookdev » Sun Mar 10, 2019 6:30 am

esmith wrote:Then you can use various methods to parse down the scatter system. Scopes, gradients...decimate points, etc.

...but you can also see some edges where I'm stamping down the grass with scopes,etc...


Thank you. You mention scopes. I couldn't find anything showing how to use them. I've opened another topic on this.
lookdev
 
Posts: 52
Joined: Sun Apr 30, 2017 1:08 pm

Re: Scattering small vegetation: grass fields, corn fields..

Unread postby Kramon » Sun Mar 10, 2019 2:43 pm

use procedural noise to blend between diffrent types of scatters... make layers of scatters like nature... use collision detections to even more fill blank spaces.
Kramon
 
Posts: 69
Joined: Sat Nov 15, 2014 8:15 pm

Re: Scattering small vegetation: grass fields, corn fields..

Unread postby Akam » Mon Mar 11, 2019 1:34 pm

Like Kramon allready mentioned I ment procedural noises to drive distribution. Of course you can also paint some distribution maps in another app and bring that in as texture.
Akam
 
Posts: 45
Joined: Thu Jan 11, 2018 6:39 pm


Return to General Discussion