Smoke Rings

At the Burning Life festival, I saw a Linden-made object which would poof out smoke rings vertically. The rings were not solid, rather they were made of a ring of particles traveling in the trajectory of a cone, giving the illusion of a ring.

I'm currently making a fun Christmas pipe for Neualtenburg and would like to integrate this ring into the object.

Does anyone know how to make a smoke ring or whom I might ask for assistance (including Lindens)? I'll post the results in the script forum, if I'm successful in procuring an open-source version.

~Ulrika~

Hmmm... probably using a particle script of type ANGLE, set to 360 degrees, with a constant low speed, and a force acting upwards on the particles.

Yes but all eight (or so) particles would emit simultaneously in a cone. Could it be that there were eight prims, each pointing slightly off bore sight that emitted a single particle at once?

I say that because these eight (or so) particles emulated a perfect ring.

Is this truly as easy as you imply in the post above (I have my doubts) or is there something trickier going on?

~Ulrika~

I just built it as described above in world and it works fine, Ulrika.

Oh, I forgot a step... I set the max age to a very short interval, and kept re-calling the particle system with a timer.

Of course, then SL became a total fucktard and kicked me out and absolutely will not let me actually connect to anything.

couldnt PSYS_SRC_PATTERN_ANGLE_CONE be used as the pattern?

Actually, Toy's method would be even easier, I think.

This is approximately what I used (it'll take tweaking):

updateparticles()
{
        float   rate  = 0.1 ;	// The delay between bursts of particles, in seconds
        float   age   = 5 ;  // How long each particle lives, in seconds
        integer count = 20 ;	// How many particles get created per burst
                 
        llParticleSystem( [
        PSYS_SRC_PATTERN, PSYS_SRC_PATTERN_ANGLE, 
        PSYS_SRC_BURST_PART_COUNT,(integer) count,	// defined above
        PSYS_SRC_BURST_RATE,(float) rate,		// defined above 
        PSYS_PART_MAX_AGE,(float) age,			// defined above
        PSYS_SRC_BURST_RADIUS,(float) 0.05,		// How far from emitter new particles start,
        PSYS_SRC_OUTERANGLE,(float) PI,			// Angle defining ANGLE or ANGLE_CONE
        PSYS_SRC_BURST_SPEED_MIN,(float) 0.2,    	// Minimum velocity for new particles
        PSYS_SRC_BURST_SPEED_MAX,(float) 0.2,    	// Maximum velocity for new particles
        PSYS_SRC_ACCEL,(vector) < 0, 0, 0.25 >,		// Acceleration affecting particles
        PSYS_PART_START_SCALE,(vector) < 0.2, 0.2, 0 >,	// Start Size, (minimum .04, max 10.0?)
        PSYS_PART_END_SCALE,(vector) < 0.4, 0.4, 0 >,	// End Size,  requires *_INTERP_SCALE_MASK
        PSYS_PART_START_COLOR,(vector) < 0.8, 0.8, 0.8 >,		// Start Color, (RGB, 0 to 1)
        PSYS_PART_START_ALPHA,(float) 1.0,		// StartAlpha (0 to 1),
        PSYS_PART_END_ALPHA,(float) 0.0,		// EndAlpha (0 to 1)
        PSYS_SRC_MAX_AGE,(float) 0.2,			// Maximum life of emitter ( 0 = forever )
        PSYS_PART_FLAGS,
             PSYS_PART_INTERP_SCALE_MASK |		// Particles change size using *_END_SCALE
         0
        ] );
}

default
{
	state_entry()
	{
		llSetTimerEvent( 1 ) ;
	}
	
	timer()
	{
		updateparticles() ;
	}
}

I did one that looked ok IMHO, I just used a very slow inviso-bullet and a loop that increased my burst radius. This may not scale down well though if you're looking for a attachment version, mine was for my pet dragon so it was fairly large scale

L8r,
UU