Pattern: PStochasticPattern

PStochasticPattern is the superclass of all chance-based patterns.

It contains its own random number generator and state, so that it can be seeded independently of other RNG processes in the application. When it is created, a random seed is generated and stored. When reset() is called, the pattern's RNG is re-seeded with this same seed, allow it to rewind to the beginning of its random pattern.