Shaw <sha### [at] activech> wrote:
> There is a company that does plug-ins for high end pricey renderers,
> there is an animation of a box being filled with a liquid that is
beyond
> belief, for me anyway.  The website is www.areteis.com, click on the
> picture of the half filled blue liquid box and download the animation.
> Then let's figure out a way to do it......  Notice that just before
the
> "water" hits the floor of the box there is a induced split in the
liquid
> it seems, in order to make it flow around the box.  Anyone know of
> literature on how this would be attempted?

Certainly a very impressive animation (as is the company's list of
projects) - what particularly impressed me was the turbulence and the
'clinginess' of the liquid to the box's sides.  This leads me to guess
that the algorithm they used was a particle system that takes into
account the surface tension of the liquid, perhaps interpolating the
surface to join the particle points in space (they describe it as an
implicit surface rendering).  This might explain the split that seems to
occur before the initial splash: the water on the outside of the column
would be held back by the surface tension, causing a sort of peeling
effect (at least that's what it looks like to me).

To recreate such an effect in POV-Ray... well, it's definitely an
ambitious idea (but never say never!).  The idea of smoothly
interpolating the liquid surface was what lead me to create the Liquid
Spray include file using blobs, and to my mind such a technique still
holds plenty of possibilities (particularly given that blobs are
perfectly suited to raytracing, even with thousands of components).
Collision detection is obviously a must: Ron's trace {} function is
again particularly suited to the raytracing environment, and I trust
(hope?!) that inclusion in the official POV-Ray is not far off.

This leaves the accurate (or at least convincing) simulation of surface
tension: perhaps adding friction to those particles in contact with
air/other objects (rather than other particles) would be feasible.  As
far as I know the actual physics of liquid turbulence are (as yet) far
from fully understood, but obviously realistic simulations (as evidenced

Post a reply to this message