Core/Random: switch to 128bit engine and fully rely on its builtin seed initialization methods

src/common/Utilities/PCGRand.cpp

@@ -25,11 +25,7 @@
 
 PCGRand::PCGRand()
 {
-    std::random_device dev;
-    if (dev.entropy() > 0)
-        _state.seed(pcg_extras::seed_seq_from<std::random_device>());
-    else
-        _state.seed(uint64(time(nullptr)));
+    _state.seed(pcg_extras::seed_seq_from<std::random_device>());
 }
 
 uint32 PCGRand::RandomUInt32()                            // Output random bits

src/common/Utilities/PCGRand.h

@@ -40,7 +40,7 @@ public:
     void operator delete[](void* ptr);
 private:
 
-    pcg32 _state;
+    pcg64 _state;
 };
 
 #endif // PCGRand_h__