need help with particles.

hey, just knocked this together very quickly. This is a VERY basic example of a particle engine.
the way i see it is, it works by creating a type, with say 50 objects. each object has

the point it starts at,
a speed at which it travels at,
a set distance or time it travels for that speed at
and each also has a fade, to make it look better

this applies only to my system below, as i say, there is much better particle engines out there.
i used low poly spheres so i could post the code and it could run on anyone computer with blitz.
Most people use sprites with say a firey looking texture if they were doing a particle engine for fire.

Graphics3D 800,600; set graphics mode
SetBuffer BackBuffer(); set to double buffering


light=CreateLight(); create a light

camera=CreateCamera(); create a camera
PositionEntity camera,0,5,-13; and position it back from the particles

cube=CreateSphere(2); create the low poly sphere for the particles to copy
PositionEntity cube,-50,0,0; position it out of view
EntityColor cube,255,20,20; change the color to red

Gosub setup; goto the type setup subroutine (not really needed)

timer=30; the time in milliseconds in which the next particle will be generated, the lower the number the more that will be generated
timer1=MilliSecs()

While Not KeyHit(1)






If MilliSecs()>timer1+timer Then
            Gosub createparticle; if the timer reaches 100 milliseconds then goto the createnewparticle sub-routine. then reset the timer
            timer1=millisecs()
end if
Gosub updateparticles; update the particles ie, move them

UpdateWorld()
RenderWorld()
Flip
Wend
End


.updateparticles
	For p.particle=Each particle; cycle thru all the available type objects
		p\y=p\y+p\speed; move the particle upwards according to it's speed
		EntityAlpha p\entity,(p\distance-p\y)/p\distance; fade the entity as it comes to the end of it's distance
		PositionEntity p\entity,p\x,p\y,0; position the entity on screen in it's updated place
		If p\y>p\distance Then FreeEntity p\entity:Delete p.particle; if the entity reaches its max distance then free the entity and delete the type object
                                                                                      ;(ALWAYS FREE THE ENTITY FIRST)
	Next
Return

.createparticle
	p.particle=New particle; create a new type object
	p\entity=CopyEntity(cube); copy the cube entity into the type object
	p\y=0
	p\x=Rnd(-3,3); set a random x position
	p\speed=Rnd(0.01,0.9); set the speed the particle will travel at
	p\distance=Rnd(2,15); set the max distance the particel can travel
Return

.setup
	Type particle; set up the type fields
		Field entity
		Field x#,y#
		Field speed#
		Field distance#
	End Type
Return

other links you should check out

norcs particle engine
http://www.blitzcoder.com/cgi-bin/showcase/showcase_showentry.pl?id=norc02062003164813&comments=no

hope some of this helps :D