Added love.math.newRandomGenerator. Returns a RNG object with its own seed and random methods.

--HG--
branch : math-randobject

src/modules/math/MathModule.cpp

@@ -18,7 +18,7 @@
  * 3. This notice may not be removed or altered from any source distribution.
  **/
 
-#include "modules/math/MathModule.h"
+#include "MathModule.h"
 #include "common/math.h"
 
 #include <cmath>
@@ -81,60 +81,22 @@ namespace math
 
 Math Math::instance;
 
-// 64 bit Xorshift implementation taken from the end of Sec. 3 (page 4) in
-// George Marsaglia, "Xorshift RNGs", Journal of Statistical Software, Vol.8 (Issue 14), 2003
 Math::Math()
-	: last_randnormal(numeric_limits<double>::infinity())
+	: rng(newRandomGenerator())
 {
-	// because it is too big for some compilers to handle ... if you know what
-	// i mean
-	union
-	{
-		uint64 b64;
-		struct
-		{
-			uint32 a;
-			uint32 b;
-		} b32;
-	} converter;
-
-#ifdef LOVE_BIG_ENDIAN
-	converter.b32.a = 0x0139408D;
-	converter.b32.b = 0xCBBF7A44;
-#else
-	converter.b32.b = 0x0139408D;
-	converter.b32.a = 0xCBBF7A44;
-#endif
-	rng_state = converter.b64;
-
 	// prevent the runtime from free()-ing this
 	retain();
 }
 
-uint64 Math::rand()
+Math::~Math()
 {
-	rng_state ^= (rng_state << 13);
-	rng_state ^= (rng_state >> 7);
-	rng_state ^= (rng_state << 17);
-	return rng_state;
+	if (rng)
+		rng->release();
 }
 
-// Box–Muller transform
-double Math::randnormal(double stddev)
+RandomGenerator *Math::newRandomGenerator()
 {
-	// use cached number if possible
-	if (last_randnormal != numeric_limits<double>::infinity())
-	{
-		double r = last_randnormal;
-		last_randnormal = numeric_limits<double>::infinity();
-		return r * stddev;
-	}
-
-	double r   = sqrt(-2.0 * log(1. - random()));
-	double phi = 2.0 * LOVE_M_PI * (1. - random());
-
-	last_randnormal = r * cos(phi);
-	return r * sin(phi) * stddev;
+	return new RandomGenerator();
 }
 
 vector<Triangle> Math::triangulate(const vector<vertex> &polygon)