Hi again, guys. I recently did a LITTLE work on using camera.position as a standard PS emitter. (standard particle emitters can be mesh or a vector3… and camera.position is a vector3.)
https://playground.babylonjs.com/#36UHXZ#36
(pardon the sparkly-particles custom updater)
I just barely started… mostly working in lines 120-125. It is quite easy to drive the camera fast-enough to exit its around-the-cam particle cloud. My goal was getting particles spraying from the entire edges of the render canvas… toward screen center. I started a thread about it… but few were interested or knew of solves. (yawn)
Also, Darcey… you might have noticed some problems with “depth sorting” and other alpha-related things… on standard particles. Expected behavior. Since standard particles are sort of like a single ground grid that has been divided-up into separate cells, the particles can only be depth-sorted IN-FRONT-OF, or BEHIND other mesh. I’m quite sure standard particles cannot be both behind and in-front-of other mesh… at the same time.
But maybe it can be done… using multiple particle systems. They are lightweight… no problems using many. 
Standard particles have an age (maxLifetime) that determines when they recycle… and they gentle-change from color1, to color2, to colorDead… across their lifetimes… so that gives you SOME fade-out features… time-based, not distance-from-emitter-based.
There are helpers nearby that are WAY smarter than I… on these subjects (such as Jerome). Generally, I am just a playground librarian. heh. I should just shut-up, really. 