[sldev] Particles in the new viewer.

[Argent Stonecutter]

There seems to be a change in the way particles are handled in the  
new viewer.

I'm seeing fewer particles, but fewer sources with no particles.

I'm also occasionally seeing sources vanish when I get close and the  
field of view puts the centroid of the particle field off-screen, but  
the source is on-screen.

I'd have put it down to my imagination except for that last point.

Nicholaz? You want to poke at the code? :)