The initial speed, in units per second, for newly spawned particles. Animatable.
- iOS 8.0+
- macOS 10.10+
- Mac Catalyst 13.0+
- tvOS 9.0+
- watchOS 3.0+
Particles begin moving at this speed in the direction determined by the
emitting property. Their directions and speeds may change thereafter according to the
acceleration property or physics effects (see the
collider properties). You can randomize the speed of newly spawned particles with the
Particle speed is measured in units (of the local coordinate space containing the particle system) per second.
The default value is
0 units per second, specifying that newly emitted particles are stationary until otherwise influenced.
You can animate changes to this property’s value. See Animating SceneKit Content.