Note, I suspect Rng::rollClosedProbability() is not needed. The only difference between it and rollProbability() is that one time in 37k (on Windows), it will give an output of 1.0.
On some versions of Linux, the value of 1.0 will occur about 1 time in 4 billion.
conversion from 'const float' to 'int', possible loss of data
conversion from 'double' to 'int', possible loss of data
conversion from 'float' to 'int', possible loss of data
