Re: Particle systems

["Keith Lucas" <klucas@atlan-tech.com>]

>- As soon as a particle is emitted, it's independend from the emitter.
>- (Simple) Particels are defined by: x,y,z,direction,speed,mass, "looks",
>timeToLife, (dieFunc)
>- (Simple) "looks" are defined by type (pixel, image), color, size, map,
>alphamap, animator
>
>All your FX are/can be particels (clouds, dust, fire, smoke, ...).

Got all that stuff running.

>There is usually no need for "local" and "global" particels.
>Maybe I missed your point, but I didn't understand the real question.

Well no ... the question was what people did. The reason for having local and
global ones is merely for optimising the drawing: each system can be culled in
one go based on its visibility.

{ I guess it doesn't even have to run if it's not visible... it could just be
frozen until it shows up again... no-one would notice :-}

I'm just concerned about the amount of effort in culling a huge list of
particles... even if they can be done by regarding them pretty much as points.
Also I was thinking about cheating and using some of the particle emissions
several times: instead of 16 fires all throwing off particles, you could have 4
drawn 4 times, which quarters the amount of the physics to do, even if not the
drawing... or am I being completely paranoid about this?

What would you do about particles that can themselves emit particles? I'm
thinking of things like sparks that could break up when they land into smaller
sparks or maybe the debris from an explosion which trails smoke particles behind
it.