G4QuickRand.hh

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#ifndef G4QUICKRAND_HH
#define G4QUICKRAND_HH
 
#include "G4Types.hh"
#include <cstdint>
 
inline G4double G4QuickRand()
{
  static const G4double f = 1. / 4294967296.;  // 2^-32
 
  // Algorithm "xor" from p.4 of G.Marsaglia, "Xorshift RNGs"
  static G4ThreadLocal uint32_t y = 2463534242;
  uint32_t x                      = y;
  x ^= x << 13;
  x ^= x >> 17;
  x ^= x << 5;
  y = x;
  return x * f;
}
 
#endif  // G4QUICKRAND_HH