Particle collision problem
 

been trying to help someone out with a presentation. Blobby surface particles hit a planer object then run off. Comes out pretty good but when the camera pans around the plane object the particles are actually showing through on the other side. Anyone know how to stop this?

2 ways that I know of off the top of my head:

1. A cheat, but isn't that what all VFX is anyway?
Take another plane, and place it slightly above the other one,
the distance above the other depends on how far your
particles are going through the original plane.
Make it collide with the particles using the same settings
as the other surface, then render with its' Primary Visibility off:)

- OR -

2. From the docs:
"In repeated or numerous collisions, particles might pass through the geometry because of insufficient collision detection sensitivity. You can increase sensitivity to avoid this problem.

To adjust the collision detection sensitivity:

Select the particle object.
In the Attribute Editor's Collision Attributes section, increase Trace Depth.
The Trace Depth sets the maximum number of collisions Maya can detect for the object in each animation time step. For instance, with a setting of 2, Maya checks twice in a frame. Any more than two collisions are ignored and the subsequent particles penetrate. Increasing the setting increases processing.

Tips:
You can set Trace Depth to 0 to make a particle object pass through geometry. You can optionally add a traceDepthPP attribute to a particle shape node to set collision detection sensitivity on a per particle basis (see Understanding particle attributes). When added, traceDepthPP appears in the Per Particle (Array) Attributes section of the Attribute Editor. The traceDepthPP setting overrides the Trace Depth setting."

Water and fluids
 

anyone know of a good way to make water filling and pouring from a container? convincingly? Tried the particles with fields thing but that isnt working too well. and maya fluids is taking up way to many resources with poor results

it appears that that is the only way to do it rage, you need an invisible layer

yeah, colliding with a plane will usually still see the edges of particles on the other side. Mostly because it's the particle's center point that the collision registers with in most cases.

I'd think colliding with a cubic object with some thickness, rather than a flat plane, would alleviate that a bit.

Re: Water and fluids
 

This should get you part of the way there:
http://www.simplymaya.com/tutorial_links.mhtml

Find the tut link for jozvex and
check out his interparticle collisions tutorial.

(click on the MAIN big image on his main page for the tuts)

Great guy, helped me out with this in the past a bunch:)