Legacy Documentation: Version 5.2
Particle System Modules
Emission Module

Main Module

This module contains global properties that affect the system overall. The name shown for it in the inspector is actually the name of the GameObject the Particle System component is attached to.

Properties

Property: Function:
Duration The length of time the system will run.
Looped If enabled, the system will start again at the end of its duration time and continue to repeat the cycle.
Prewarm If enabled, the system will be initialized as though it had already completed a full cycle (only works if Looping is also enabled).
Start Delay Delay in seconds before the system starts emitting once enabled.
Start Lifetime The initial lifetime for particles.
Start Speed The initial speed of each particle in the appropriate direction.
Start Size The initial size of each particle.
Start Rotation The initial rotation angle of each particle.
Start Color The initial color of each particle.
Gravity Multiplier Scales the gravity value set in the physics manager. A value of zero will switch gravity off.
Inherit Velocity Do the particles start with the same velocity as the particle system object?
Simulation Space Should particles be animated in the parent object’s local space (and therefore move with the object) or in world space?
Play on Awake Does the system start automatically when the object is created?
Max Particles The maximum number of particles in the system at once. Older particles will be removed when the limit is reached.

Details

The system emits particles for a specific duration but can be set to emit continuously using the Looped property. This means you can create, say, smoke in short puffs or in a steady stream. The “Start” properties (for lifetime, speed, size, rotation and color) specify the state of a particle on emission but other property groups (such as Size Over Lifetime) can modify the values as the system progresses. Also, all of these properties can have randomised values in a range specified by curves. All particle systems use the same gravity vector specified in the physics settings but the Gravity Multiplier value can be used to scale the gravity or switch it off if set to zero (dust clouds will fall to earth but not at the same rate as solid objects). The Inherit Velocity and Simulation Space properties together determine whether the particles move with the particle system object or independently in the game world. Systems like clouds, hoses and flamethrowers will tend to leave trails that persist in world space even if the object producing them moves around. On the other hand, when particles are used to create a spark between two electrodes, the spark should move along with the object.

Particle System Modules
Emission Module