The range of randomized friction coefficients for particles. Animatable.
Mac Catalyst 13.0+
Setting a nonzero value for this property randomizes the effect of the particleFriction property. SceneKit randomly adjusts the friction coefficient of each particle by up to half the particleFrictionVariation value. For example, if the particleFriction value is 1.0 and the particleFrictionVariation value is 0.5, each particle uses a random friction coefficient between 0.75 and 1.25 for physics simulation.
The default value is 0.0, specifying no randomization.