Two basic random number generators, Cmwc is supposed to be a pretty good one.

I need to get the base class and singleton interface in place.

4 files changed, 104 insertions, 3 deletions

diff --git a/src/experimental/randombasic.cpp b/src/experimental/randombasic.cpp
index 03bf7fe..ac591be 100644
--- a/src/experimental/randombasic.cpp
+++ b/src/experimental/randombasic.cpp
@@ -8,8 +8,24 @@
 #include "bu/randombasic.h"
 
 Bu::RandomBasic::RandomBasic() :
-        c( 6364136223846793005 ),
-        m( 1442695040888963407 )
+        a( 6364136223846793005 ),
+        c( 1442695040888963407 ),
+        x( 0 )
 {
 }
 
+Bu::RandomBasic::~RandomBasic()
+{
+}
+
+void Bu::RandomBasic::seed( int32_t iSeed )
+{
+        c = iSeed;
+}
+
+int32_t Bu::RandomBasic::rand()
+{
+        x = (a*x + c);
+        return (int32_t)x;
+}
+
diff --git a/src/experimental/randombasic.h b/src/experimental/randombasic.h
index 2ba7bd3..6eab9dc 100644
--- a/src/experimental/randombasic.h
+++ b/src/experimental/randombasic.h
@@ -17,8 +17,12 @@ namespace Bu
                 RandomBasic();
                 virtual ~RandomBasic();
 
+                void seed( int32_t iSeed );
+
+                int32_t rand();
+
         private:
-                int64_t c, m, a;
+                int64_t a, c, x;
         };
 };
 
diff --git a/src/experimental/randomcmwc.cpp b/src/experimental/randomcmwc.cpp
new file mode 100644
index 0000000..97f7262
--- /dev/null
+++ b/src/experimental/randomcmwc.cpp
@@ -0,0 +1,52 @@
+/*
+ * Copyright (C) 2007-2012 Xagasoft, All rights reserved.
+ *
+ * This file is part of the libbu++ library and is released under the
+ * terms of the license contained in the file LICENSE.
+ */
+
+#include "bu/randomcmwc.h"
+
+#define PHI 0x9e3779b9
+
+RandomCmwc::RandomCmwc() :
+        q( NULL ),
+        c( 362436 )
+{
+        q = new uint32_t[4096];
+}
+
+RandomCmwc::~RandomCmwc()
+{
+        delete[] q;
+}
+
+void RandomCmwc::seed( int32_t iSeed )
+{
+        int i;
+
+        Q[0] = iSeed;
+        Q[1] = iSeed + PHI;
+        Q[2] = iSeed + PHI + PHI;
+
+        for (i = 3; i < 4096; i++)
+                Q[i] = Q[i - 3] ^ Q[i - 2] ^ PHI ^ i;   
+}
+
+int32_t RandomCmwc::rand()
+{
+        uint64_t t, a = 18782LL;
+        static uint32_t i = 4095;
+        uint32_t x, r = 0xfffffffe;
+        i = (i + 1) & 4095;
+        t = a * Q[i] + c;
+        c = (t >> 32);
+        x = t + c;
+        if( x < c )
+        {
+                x++;
+                c++;
+        }
+        return (Q[i] = r - x);
+}
+
diff --git a/src/experimental/randomcmwc.h b/src/experimental/randomcmwc.h
new file mode 100644
index 0000000..3a05383
--- /dev/null
+++ b/src/experimental/randomcmwc.h
@@ -0,0 +1,29 @@
+/*
+ * Copyright (C) 2007-2012 Xagasoft, All rights reserved.
+ *
+ * This file is part of the libbu++ library and is released under the
+ * terms of the license contained in the file LICENSE.
+ */
+#ifndef BU_RANDOM_CMWC_H
+#define BU_RANDOM_CMWC_H
+
+#include <stdint.h>
+
+namespace Bu
+{
+        class RandomCmwc
+        {
+        public:
+                RandomCmwc();
+                virtual ~RandomCmwc();
+
+                void seed( int32_t iSeed );
+
+                int32_t rand();
+
+        private:
+                uint32_t *q, c;
+        };
+};
+
+#endif