A mask that defines which categories of physics fields can exert forces on the particles.
- iOS 8.0+
- macOS 10.10+
- tvOS 9.0+
- watchOS 3.0+
When a particle is inside the region of a
SKField object, that field node’s
category property is compared to the emitter’s
field property by performing a logical AND operation. If the result is a non-zero value, then the field node’s effect is applied to the particle as if it had a physics body. The physics body is assumed to have a
1 and a
The default value is
0x00000000 (all bits cleared).