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GraphXs
11-29-2012, 08:23 AM
:help:
How do I animate grass in wind using LW11 Instancing?

I have a plane
I have a clumped grass blade objects with a weight map on the Y axis.

How can I use the weight-map on the grass to only distort the top of the grass and use a Null to push the distortion through it? So it will act like wind?

I see that I can displace the grass, but how can I have the bottom stay fixed with the weight map and use a displacement?

Thanks

dwburman
11-29-2012, 09:43 AM
I tried to do this by using an animated texture on the instance's rotation.

It's not as cool as having only the tops of the plant move, and you can't have wide and deep patches of grass, but it does work in some scenarios.

Here's a test render. well, a test render repeated several times:


http://youtu.be/KME6rfDTFuk

It's probably not the best test render I have, but it's one I found that was ready to go that didn't have problems with trees in the scene that were misbehaving and distracting.

GraphXs
11-29-2012, 10:57 AM
I tried to do this by using an animated texture on the instance's rotation.

It's not as cool as having only the tops of the plant move, and you can't have wide and deep patches of grass, but it does work in some scenarios.

Here's a test render. well, a test render repeated several times:


http://youtu.be/KME6rfDTFuk

It's probably not the best test render I have, but it's one I found that was ready to go that didn't have problems with trees in the scene that were misbehaving and distracting.


Can you explain or share your scene?

Did u just use a procedural texture to animate it?

Looks Great!

Thanks

GraphXs
11-29-2012, 11:04 AM
Are all the Instances just a single flower/blade of grass. so they are rotating from each pivot?

DrStrik9
11-29-2012, 02:16 PM
One very simple way to use a weight map for displacement:

109516

dwburman
11-29-2012, 02:25 PM
I haven't worked on this in over six months, so I don't quite remember all ins and outs of it.

I had several sets of clumps of grass, not single blades. They rotate around the pivot points. They also have an mdd driving the small animation of the blades moving independently.

As for the wind movement, it's a procedural texture that uses a null as the reference object, so the null controls the wind direction and speed. Well, the wind is always blowing in one direction because the grass only rotates in one direction, but the null controls the pattern of the rotation.


It needs some tweaking. I just rewatched one of the later tests, and it seems a bit too mechanical.

GraphXs
11-29-2012, 09:40 PM
Thanks! I will try some of those methods. I did get it to work with just a single blade instanced.