View Full Version : Need help sweating ...

06-13-2006, 04:55 PM
Hiya. I would call myself an advanced beginner. I saw the NewTek video tutorial on an easy way to make sweat. It's a simiple emitter and collision setup with hypervoxels. It works fine until I animate the character with bones. The collision object (the surface of the character's face) is frozen in the first frame and doesn't change, so the sweat is rolling off of a ghost. I'm going (almost) nuts trying to figure this out. :stumped:

06-13-2006, 05:36 PM
Presumably the collision object is also using the bones from your main character?

06-13-2006, 05:51 PM
Yes, the collision object (the face) is using bones; the emitter, his brow, supposedly should be using the same bones. Thanks for taking a look. Here's the tutorial I was talking about:


06-13-2006, 06:16 PM
I too used that same tutorial to make a can sweat.
All is well and good until a bone transformation is applied (moving the object in the XYZ and rotating is fine - the sweat follows along like a champ). When bone action is used the emitter/collision object relationship seems to wants to follow the "bones at rest" position of the object.

The tutorial states that hitting "calculate" isn't needed and a simple scrub through will do the trick. I calculated anyway and during the calculation the mesh seemed to follow the bones just fine, but after the calculation finished it just reverted to the rest state in the open GL and on render.

In my case the the can has the original bones and is the collision object, and a couple of rows of polys near the top neck of the can are the emitter and share the the can's bones.


06-13-2006, 06:38 PM
After calculating you must save the particle motion to a .pfx right after you get the result you like, otherwise during render time it usually doesn't work.

Pantagrool - So, you have you character, and a seperate face surface which is the collision object and they are both being driven by the same bones. Is the collision object, part of the same charater, but in a different layer? Or is it a completely seperate object? Is it SubD and what have you got the method set too - after bones or last?

06-13-2006, 07:29 PM
Hey, Steve.
I just got off the phone with JoePoe and, using your advice, we got it to work. As I suspected -- it was a one-button solution (two, in this case). Thanks a lot.


06-13-2006, 07:35 PM
THANKS SteveC - that did the trick. Save the .pfx after calculation - GOT IT!

By the way I know Pantagrool (we've been learning Lightwave together).
We both thank you.

One last question:
At one point the can does a pretty violent wiggle and the sweat beads fly off.
I'm not sure yet if that is a good thing, I just want to know how to have full control over the drops in order to make that decision. To get the drops to stay on the can I've been playing with the Stick % on the can (collision object). At one point I had it up to 10,000% and they still flew off.
Any suggestions?

06-13-2006, 08:01 PM
You could try playing with the weight and gravity of the beads in conjunction with the collision friction.

Dynamics are very much a trial and error area and a case of trying different things - but glad you got it working for the most part :)