Range
Vec2 = [0, 1] x is the result at r = 0 and y the result at r = 1. The two ends need not be in order.
A float driver that returns a random value spread evenly over
Range: Range.x + (Range.y - Range.x) * r, where r is the driver's random number
between 0 and 1. When r is drawn and whether it is shared between particles is
described under Random values on IVfxBaseDriver.
Vec2 = [0, 1] x is the result at r = 0 and y the result at r = 1. The two ends need not be in order.