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SteveH
06-04-2014, 11:41 AM
HI - the title says it all. Can you have a field of instanced grass and have it displace using a null - or an animated texture? What I don't want is having all the instanced all displace exactly the same way at the same time - rather a wave of wind type of thing. Is that possible? Thanks in advance!

JohnMarchant
06-04-2014, 12:46 PM
Im not at LW at the moment, what about animated displacement map using a null for all the grass. After all all the grass will follow a similar pattern in the wind.

spherical
06-04-2014, 03:25 PM
My first thought, probably SO not possible..., is a moving procedural with a weight map or falloff on height.

prometheus
06-04-2014, 03:39 PM
I really donīt see any way to to that with instances, since you would only repeat the instaced grass or grass patch, thus when using repeated instances ..every such repeat will be localy and the same for each instance and not globally over the whole area.

Bring back sasquatch for large grass fields and wind dynamics.

Michael

jhinrichs
06-04-2014, 04:39 PM
There's this example:

http://www.youtube.com/watch?v=KME6rfDTFuk

He animated the grass ripple with "... an animated texture on the instances rotation." I haven't done enough instancing to know what he means by that, but it's possible.

prometheus
06-04-2014, 05:20 PM
There's this example:

http://www.youtube.com/watch?v=KME6rfDTFuk

He animated the grass ripple with "... an animated texture on the instances rotation." I haven't done enough instancing to know what he means by that, but it's possible.

well..yeah, gives some rotational movement, might work for distance shot, but it just rotates the base of ther flowers, would need additional bend, maybe with each flower also having a slight bend morph...but not sure it would look good or realistic, the sample is just some sort of wiggling really, I would think rendering out several grass passes in layers and composite might be the way, so you treat a certain area indivdually, maybe actually with fiberfx or sas really instead of instances.

jeric_synergy
06-04-2014, 06:21 PM
I think Rotation would work fine, except for botanists in the audience. ;)

I'd use a RIPPLE procedural, set far away so the ripples were basically parallel, and then w/a layer displacement on top of that to break it up >>slightly<<. That would get the "waves of wind" effect. Of course, the mesh needs to LOOK different as it rotates, so the geometry & surfacing need to work together on that.

By that I mean: the reason "Quaking Aspen" trees have their distinctive look is that the leaves' tops and bottoms are markedly different in luminance. If they were the same, a grove in the wind would look totally different.

Varying the opacity of the two layers would break it up even more.

Please post when you get something like what you were thinking. :thumbsup:

SteveH
06-04-2014, 07:34 PM
All great ideas guys! Definately something to try out. Maybe someone here at Newtek would do a tutorial....although to be honest - tutorials have been pretty sparse lately. Hopefully working feverishly on LW12!

jeric_synergy
06-05-2014, 10:35 AM
A good source of in-depth discussion are videos of LALWUG meetings, available on YouTube.

Also, the LW3dG has many many tutorials in their "Learn" section:
https://www.lightwave3d.com/learn/