This is just an .avi of an accident that came about when I was playing
with Chris Huff's particle patch.

A blobby stream of "paint" is shot into the wall and bounces off it onto
the floor.  Not content with that, the goo
crawls over to the wall, climbs up, and oozes into the surface.

All just one particle system and one emitter.

I don't know exactly why it did this; I think it's because I used
variable elasticity, but I kind of like it.


Mike Wilson

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Attachments:
Download 'wall.zip' (45 KB)

That's very weird.  Tries to get to the target no matter what I suppose.

Bob

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In article <397DDFCD.5C5083F4@iastate.edu>, Mike Wilson 
<maw### [at] iastateedu> wrote:

> A blobby stream of "paint" is shot into the wall and bounces off it onto
> the floor.  Not content with that, the goo
> crawls over to the wall, climbs up, and oozes into the surface.

Hmm, maybe if you increased the component's radius, it would look more 
"fluid".
This animation demonstrates one of the problems with my patch: the 
liquid's volume isn't conserved. Inter-particle forces can help to fix 
this, but they still need work.


> I don't know exactly why it did this; I think it's because I used
> variable elasticity, but I kind of like it.

The only thing I can think of: did you use wind? It looks like you have 
a strong, slightly upward force pulling the particles along the wall.
What do you mean by variable elasticity?

Chris thinks...
Did you decrease the elasticity in the system for each successive frame? 
That might make this effect...at first, particles would bounce away from 
the wall. Then, as the amount of energy they loose increases, they would 
bounce closer to the wall, and eventually would lose enough energy to 
slow their fall. If there is wind or gravity pushing them against the 
wall, they would slowly "drip" down it.

-- 
Christopher James Huff - Personal e-mail: chr### [at] maccom
TAG(Technical Assistance Group) e-mail: chr### [at] tagpovrayorg
Personal Web page: http://homepage.mac.com/chrishuff/
TAG Web page: http://tag.povray.org/

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Chris Huff wrote:

> Did you decrease the elasticity in the system for each successive frame?
> That might make this effect...at first, particles would bounce away from
> the wall. Then, as the amount of energy they loose increases, they would
> bounce closer to the wall, and eventually would lose enough energy to
> slow their fall. If there is wind or gravity pushing them against the
> wall, they would slowly "drip" down it.

You called it right.  Elasticity is set to "clock-1" and there is a a gravity
vector pulling the particles toward the wall and down to the floor.

The effect you describe is what I was looking for, but I couldn't get the drip
part right.  The particles just seemed to "boil away" rather than slide toward
the floor.  I hadn't tried the ipf{...} stuff yet because it added too much
time to the parse for something I was just fooling around with.

Mike.

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