When using one of the animated modes, how quickly to move the emission position around the arc.
The value is specified in terms of the number of complete 360 degree rotations. A value of 2 would mean that the emission position rotated 2 full times per second. See Also: ParticleSystem.ShapeModule.arcMode, ParticleSystemShapeMultiModeValue, ParticleSystem.ShapeModule.shapeType.