Particle spawn radius

[VideroBoy]

Right now a particle emitter shoots all particles out of its exact coordinate.

How would I go about making the particles look like they spawn anywhere within some radius around the coordinate.

I'm trying to create some kind of comet effect around a sprite, where there's a halo of particles surrounding the sprite with the ones behind trailing off. All my experiments end up with the particles either going too fast, going too far, or traveling in a cone behind the sprite with no particles in front.

[knorke]

Right now a particle emitter shoots all particles out of its exact coordinate.

I think that can not be changed.

You could move around the particle emiter using ParticleSystem:setPosition (x, y)

ie to spawn in a a=100 square around the center:
ParticleSystem:setPosition (x+math.random(-50,50) , y+math.random(-50,50))

or to spawn in a ring with r=100 around the center:
local angle = math.random (0, 3.14 * 2)
local r = 100
ParticleSystem:setPosition (x + sin (angle) *r, y +cos (angle) *r)

[VideroBoy]

So instead of having an emitter in the centre, I could have a ring of emitters around the centre at the desired radius. I guess that could work.

[TechnoCat]

So instead of having an emitter in the centre, I could have a ring of emitters around the centre at the desired radius. I guess that could work.

I believe he was actually suggesting you move the emitter around randomly.

[tentus]

Think of the emitter like a water hose. You can change the hose's angle and flow etc, but to have multiple starting locations you'll need to shake the hose around.

[VideroBoy]

I believe he was actually suggesting you move the emitter around randomly.

This is what I ended up implementing. It's good enough.