View Full Version : fluid wave dynamics

10 October 2004, 11:12 PM
Hi, here is a link to a test I made utilising clothfx on a 3-dimensional cage to produce the effect of fluid dynamics.

not only the surface is calculated, but the main body of liquid. this is shown by the movement of the particles in the water.

by dragging a reference null controlling displacement of the liquid, a wake is produced with realistic rolling waves.

10 October 2004, 12:23 AM
Very Impressive.
Can u do a tutorial on that?

Dexter | DTG
10 October 2004, 02:35 AM
Yes, a tut or posting the scene file for di-section would be great.

10 October 2004, 03:34 AM
if i understand the technique correctly from what you posted on the Newtek
forum, i think we'll need an l-script or a plugin to make the 3dimensional 2 point
polygon mesh....
Or does one exist already?

anyways thats a really cool aplication of what we have in 8(0.1)!

- Will.

10 October 2004, 03:39 AM
great idea!

10 October 2004, 05:09 AM
Colin's SBD stuff should do it in a rather automated fashion. I'm guessing...

10 October 2004, 05:34 AM
if i understand the technique correctly from what you posted on the Newtek
forum, i think we'll need an l-script or a plugin to make the 3dimensional 2 point
polygon mesh....
Or does one exist already?

anyways thats a really cool aplication of what we have in 8(0.1)!

- Will.
Its a very cool effect. Ive been playing with similar things myself including some 3D cages. Poobys example came out pretty well (Nice one Pooby!). :)

What I did to create my 3D grid is to create a grid and make an array down the z axis then another down the y axis. I then did a point merge (making sure that the squares on the grid all line up). After that I do a bevel with no inset or shift. I again do a point merge and then delete all the quads. This leaves a grid of 2 point polys. Im guessing Pooby use Smart Morph for the ripples (?).
I used normal displacement and 2 point polys on this:

10 October 2004, 07:48 AM
To make the cage I just made one cube, copy, paste, move, merge,unifypolys. copy 2 cubes paste, move, merge,unifypolys....etc etc... it only took about 5 mins to make but it would be great if there was a plug to do it.
It would be good to be able to extrude 2 point poly cubes from the surface of any shaped mesh, because this technique has many applications such as fat wobbling under skin. ( in fact, that was my original goal till I got sidetracked by the liquid)

As for the ripples,they are not like simply using a 'crumple' displacement map or someting like that, they are 'real'.. in other words, all you need to do is disturb the liquid, and the ripples just start and keep going and forming themselves.

to disturb the liquid you can use Normal Displacement on the 'ocean floor' ( as it is a fixed surface) OR you can actually use a collision object to disturb the surface or even underwater. (this is very cool)

If you drop a collision sphere quickly down through the water, it emulates a splash. (although obviously it cannot produce spray)

10 October 2004, 02:48 PM
That's pretty cool, I've made surface waves using a flat sheet but I can see where this would be a better solution. Do you have any more tests?

10 October 2004, 03:24 PM
I do have footage of a Wake forming , but I can't post it on here.. file size wont allow it..

I got someone to host that last file, but I don't want to keep pestering them to host more.

I only came up with the idea the night before last though so this whole technique is still in 'tinkering' stage.

Best thing to do is just set it up and try it for yourself. it's pretty easy to do. I had good results within an hour of setting it up.

10 October 2004, 03:27 PM
this is very cool...i just set up something in about 15 minutes, but i have a few Q's....How big and how many layers of cages do you use?....i have about 33 cubes on a side, with 2 layers up and down. I ended up using FX_metalink to make a "smooth" water object, because the cages are all cubes.

10 October 2004, 03:48 PM
That's about what I used for this test..

The finer the mesh, the more detailed the waves (and I guess more realistic the result)

The grid is all made from 2 pt polys so you did the right thing.. make a surface and apply it with metalink..

for particles use Hardlink on an object made of lots of little bits of whatever you wish.

or I guess you can use points and apply HV's to create underwater murk...

By the way.. you can make wobbly solids with this too. and thick liquids

10 October 2004, 05:45 PM
Ive also been experimenting with the muscles/fat thing as well. Ive been getting fairly good results having muscle/fat objects connected to the skin using single point polys. My experiments with waves has yielded some good results too. Ive been able to get waves to curl over pretty good. One of the tricks that has worked pretty well is to create a weight map on my grid so that the bottom is pretty well anchored but falls off gradually towards teh top. This simulates what happens when waves start to hit the beach. The water closest to the beach on the bottom slows down before the water on top which causes the curling over.
Creating the connections between the fat/muscle geometry and the skin isnt too bad. I just click the two points I wish to connect and hit the p key. I would love to see a bridge tool that would just connect points with 2 point polys. :)

10 October 2004, 07:13 PM
why not show us a test Larry.

10 October 2004, 07:55 PM
Why not show us a test Larry?

Ive got some examples rendering and Ill try to get them posted up asap. :)

Thanks! Much appreciated :)

10 October 2004, 08:18 PM
I have purchased $900.00 worth of Larry's CD's. Money well spent, as far as I am concerned.

I think I would be a little dissapointed if I saw him posting all his material from the CD's for free download. Larry has a point... and I know this would never happen anyway.

FWIW, perhaps it was not pooby's intent to ruffle feathers. Sometimes we type things without first considering GUM. (Grand Unified Message)

10 October 2004, 08:21 PM
Why not show your results?

Or do we have to buy the dvd?
I dont understand the need to post comments like this. Its not only unprofessional but it doesnt do you, me, or anyone else any good. I realize that you edited your post but seeing remarks like this coming in my email is annoying.And while that is cool and all, if he had left those comments here that is one thing, but you didn't have to repost his comments that were directed to your private email and could have kept it off list.

Both unprofessional if you ask me.

10 October 2004, 09:00 PM
Sorry Larry..

I took it off about 40 seconds after I posted that because when I re-read it, it didn't sound cheeky, as it was intended. It sounded cutting.

I genuinely am interested in seeing any tests that you have done.

10 October 2004, 09:31 PM
No problem Pooby. Its hard to determine a persons intent or unintent just off texts :)
(I will be posting up some tests btw)

The comments werent directed in a private email. The email was sent from this forum to me from a post that was first posted publically then edited.

Again, thanks! :)

10 October 2004, 07:28 AM
Heres a couple of quick tests. The first one is waves coming in but hitting some pylons and the water squeezes in between. The 2nd is an object impacting on the water at a high speed and extreme angle.

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