It would be great if there would an option to kill particles with zero alpha…. or to prevent such particles to emit another ones via Aux node.
 
I am using a animated 3d layer as en emitter. Just a cloudy/noisy B/W layer with animated properties.
I can set it to use either Color or Size from Texture to avoid having black or invisible part of the texture to emit visible particles.
But if I after that use an Aux node to add some effect in the later life of particles then the invisible particles are also emitting new ones and I basicaly get the square shape of the emitter layer.
It would be great if there would be an option that particles with zero alpha or size do not create new particles via Aux node. And also an option to kill particles with zero alpha/scale or just to put them in some disabled state so they wouldn’t be able to influence anything in setup.
 
Maybe there is a way to achieve this but I am not finding it.