Remove ancient trunk folder from svn repository

[synfig.git] / synfig-core / src / synfig / quick_rng.h

diff --git a/synfig-core/src/synfig/quick_rng.h b/synfig-core/src/synfig/quick_rng.h
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+/* === S Y N F I G ========================================================= */
+/*!    \file quick_rng.h
+**     \brief Template Header
+**
+**     $Id$
+**
+**     \legal
+**     Copyright (c) 2002-2005 Robert B. Quattlebaum Jr., Adrian Bentley
+**     Copyright (c) 2007 Chris Moore
+**
+**     This package is free software; you can redistribute it and/or
+**     modify it under the terms of the GNU General Public License as
+**     published by the Free Software Foundation; either version 2 of
+**     the License, or (at your option) any later version.
+**
+**     This package is distributed in the hope that it will be useful,
+**     but WITHOUT ANY WARRANTY; without even the implied warranty of
+**     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+**     General Public License for more details.
+**     \endlegal
+*/
+/* ========================================================================= */
+
+/* === S T A R T =========================================================== */
+
+#ifndef __SYNFIG_QUICK_RNG_H
+#define __SYNFIG_QUICK_RNG_H
+
+/* === H E A D E R S ======================================================= */
+
+#include <stdint.h>
+
+/* === M A C R O S ========================================================= */
+
+/* === T Y P E D E F S ===================================================== */
+
+/* === C L A S S E S & S T R U C T S ======================================= */
+
+// A fast 32-bit linear congruential random number generator
+class quick_rng
+{
+       uint32_t next;
+public:
+       quick_rng(uint32_t seed=0):next(seed) { }
+
+       void set_seed(uint32_t x)
+       {
+               next=x;
+       }
+
+       uint32_t i32()
+       {
+               static const uint32_t a(1664525);
+               static const uint32_t c(1013904223);
+
+               return next=next*a+c;
+       }
+
+       uint32_t i16()
+       {
+               return i32()>>16;
+       }
+
+       float f()
+       {
+               static const float m(int(65535));
+
+               return float(i16())/m;
+       }
+
+       uint32_t operator()(const uint32_t& m)
+       {
+               if(m==65536)
+                       return i16();
+               else
+               if(m<=65536)
+                       return i16()%m;
+               else
+                       return i32()%m;
+       }
+};
+
+/* === E N D =============================================================== */
+
+#endif