Trees - Mesh displacer

Started by Hannes, October 17, 2014, 12:22:12 PM

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Hannes

Just a little test for animating a population of plants. Of course the trunks are wobbling as well, but from a distance it works.

archonforest

Dell T5500 with Dual Hexa Xeon CPU 3Ghz, 32Gb ram, GTX 1080
Amiga 1200 8Mb ram, 8Gb ssd


N810

Hmmm... wonder what this button does....

bigben

Applied to a tree where the model is split up by the branching level and it could be really useful.

Dune

Good action, Hannes! So this is not by transform shader or 4D noise, but mesh displaced... mmm.  I had the idea that it would only breakup the vertices, and not move branches. This might even be a better option for distance than a heavy mdd file.

Hannes

#6
Thanks guys. Yes, from a distance it's absolutely OK. You have to do some tests to get the correct settings of the power fractal, but, as you said, Ulco, it's probably easier than having to use a vast motion file. And there is of course a transform shader to move the PF.
One more thing: the trees have all the same motion of course, but since the instances are all rotated differently and the motion is rather subtle, it's not too obvious.


Dune

So if you don't rotate them too much, say 10ยบ, you can make a bunch of synchro dancing trees  ;D

zaxxon

Thank you Hannes for your work on this technique. I certainly think it would work applied to populations of underbrush and tall grasses, areas where large motion files wouldn't work at any rate. Question: how hard would it be to vary the motion to simulate wind gusts?

Hannes

The problem is that it's the same motion for each instance of one population. To get more variety you can of course mix a few populations with different mesh displacers. It works for a subtle breeze, but at the moment I have no idea how to achieve wind gusts.

Oshyan

It does only move the vertices, but depending on the scale of the displacement, adjacent vertices may move similarly enough over small area to appear to move together, yet create a larger overall movement across the whole model (think of a noise as displacement with scale of a couple of meters, and not very small Smallest Scale).

- Oshyan

Dune

QuoteThe problem is that it's the same motion for each instance of one population.
Perhaps it is possible to feed a series of masked displacement into the mesh displacer, so make your pf's, but mask them by larger terrain areas through a transform shader set at world scale, then feed that into the mesh displacer. Theoretically (just thinking aloud) you should be able to get different movements in different parts of your pop.

Oshyan

I'm not sure that's true Ulco because if I understand correctly the mesh displacement is being applied on the *source* model for the population, and it is then instanced after that... Although you're right that color variation can work in world space, so maybe it is possible...

- Oshyan

Dune

That was my line of thinking, and yesterday I did a small experiment, but too short to see what's going on; using a vdisp shader (X displace) setup with minimum height and an X moving PF (for gusts of wind movement), taken through transform shader. I have to try again, as that opens good posibilities. If it doesn't work, maybe it can be made to work (Matt?), like the pop coloring.

Dune