The acceleration to apply to a particle’s horizontal velocity.
- iOS 7.0+
- macOS 10.9+
- Mac Catalyst 13.0+
- tvOS 9.0+
- watchOS 3.0+
This property is useful for simulating wind, gravity and other effects. It is uniformly applied to all particles generated by the emitter.
The default value is
Controlling Particle Velocity and Acceleration
The average initial speed of a new particle, in points per second.
The average initial direction of a particle, expressed as an angle in radians.
The range of allowed random values for a particle’s initial direction, expressed as an angle in radians.
The acceleration to apply to a particle’s vertical velocity.