Instance Property


A Boolean value that determines whether the system repeats its emission and idle periods.


@property(nonatomic) BOOL loops;


If this value is YES (the default), you can make the system emit particles periodically or sporadically. For example, in a looping system where the emissionDuration value is 1.0 seconds and the idleDuration value is 1.0 seconds, the system alternates alternates between equal one-second periods of spawning and not spawning particles. Use the emissionDurationVariation and idleDurationVariation properties to randomize the duration of each emission and idle period, making the emission behavior more sporadic.

Specify NO for particle systems that create one-shot effects, such as an explosion that appears when a game character is defeated.

See Also

Managing Particle Emission Timing


The duration, in seconds, over which the system spawns new particles. Animatable.


The range, in seconds, of randomized emission duration values. Animatable.


The duration, in seconds, of periods when the system emits no particles. Animatable.


The range, in seconds, of randomized idle duration values. Animatable.


The duration, in seconds, for which particles are spawned before the system is first rendered. Animatable.


The number of particles spawned during each emission period. Animatable.


The range of randomized particle birth rate values. Animatable.