Enum
ParticleEmitterShapeInOut
Controls the direction particles travel when emitted from a shaped
ParticleEmitter.
Controls whether particles emitted from a ParticleEmitter travel
outward from, inward toward, or in both directions relative to the emitter
shape surface. Used with the ParticleEmitter.ShapeInOut property,
which defaults to ParticleEmitterShapeInOut.Outward.