Add an SDL random number generator with independent seeds.

stepmania/src/RageUtil.cpp

@@ -25,6 +25,20 @@
 
 unsigned long randseed = time(NULL);
 
+RandomGen::RandomGen( unsigned long seed_ )
+{
+	seed = seed_;
+	if(seed == 0)
+		seed = time(NULL);
+}
+
+int RandomGen::operator() ( int maximum )
+{
+	seed = 1664525L * seed + 1013904223L;
+	return (seed >> 2) % (maximum + 1);
+}
+
+
 void fapproach( float& val, float other_val, float to_move )
 {
 	ASSERT( to_move >= 0 );

stepmania/src/RageUtil.h

@@ -92,10 +92,15 @@ inline int RandomInt(int nLow, int nHigh)
 	return ((Random() >> 2) % (nHigh - nLow + 1)) + nLow;
 }
 
-// Debug new for memory leak tracing
+/* Alternative: */
-//#ifdef _DEBUG
+class RandomGen
-//#define new new(_NORMAL_BLOCK, __FILE__, __LINE__)
+{
-//#endif
+	unsigned long seed;
+
+public:
+	RandomGen( unsigned long seed = 0 );
+	int operator() ( int maximum = INT_MAX-1 );
+};
 
 
 // Simple function for generating random numbers