I’m hoping to effectively make a planar source of varying intensity. With the help of previous posts I am doing this during my GeneratePrimaries(G4Event* anEvent) by generating a random position according to an array of desired intensities. I do this ny having another an array where the value at each index is the accumulative sum of all values in the intensity array up until that point. My plan was to then produce a random value between 0 and the max value of the cumulative array and get the index of the first element greater than this value, however this requires uniform random values between 0 and 7e9.
G4UniformRand seems to only produce values with ~6 decimal places of precision, is there any way to increase this?