The numbers to turn into booleans, one each.
OptionalthresholdNumbers below this are always true.
OptionalthresholdNumbers above this are always false; between the two thresholds the chance of true fades from certain to none.
OptionalnrHow many steps the fade between the thresholds has; more steps make it smoother.
Numbers, two thresholds and a step count for
logic.twoThresholdRandomGradient.