Lunchbox  1.17.0
Multi-threaded C++ toolbox library for all application developers creating high-performance multi-threaded programs.
rng.h
1 
2 /* Copyright (c) 2007-2014, Stefan Eilemann <eile@equalizergraphics.com>
3  *
4  * This library is free software; you can redistribute it and/or modify it under
5  * the terms of the GNU Lesser General Public License version 2.1 as published
6  * by the Free Software Foundation.
7  *
8  * This library is distributed in the hope that it will be useful, but WITHOUT
9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
10  * FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
11  * details.
12  *
13  * You should have received a copy of the GNU Lesser General Public License
14  * along with this library; if not, write to the Free Software Foundation, Inc.,
15  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
16  */
17 
18 #ifndef LUNCHBOX_RNG_H
19 #define LUNCHBOX_RNG_H
20 
21 #include <boost/noncopyable.hpp>
22 #include <limits>
23 #include <lunchbox/debug.h> // for LBASSERT
24 #include <lunchbox/init.h> // friend function
25 #include <lunchbox/types.h>
26 
27 namespace lunchbox
28 {
29 namespace detail
30 {
31 class RNG;
32 }
33 
43 class RNG : public boost::noncopyable
44 {
45 public:
47  LUNCHBOX_API RNG();
48 
50  LUNCHBOX_API ~RNG();
51 
60  template <typename T>
61  T get()
62  {
63  T value;
64  if (!_get(&value, sizeof(T)))
65  return T();
66  return value;
67  }
68 
69 private:
70  LUNCHBOX_API bool _get(void* data, size_t size);
71 };
72 
73 template <>
74 inline float RNG::get()
75 {
76  const float max_limits =
77  static_cast<float>(std::numeric_limits<uint32_t>::max());
78  return ((float)get<uint32_t>() / max_limits);
79 }
80 
81 template <>
82 inline double RNG::get()
83 {
84  const double max_limits =
85  static_cast<double>(std::numeric_limits<uint64_t>::max());
86  return ((double)get<uint64_t>() / max_limits);
87 }
88 
89 template <>
90 inline bool RNG::get()
91 {
92  return (get<uint32_t>() & 1);
93 }
94 }
95 #endif // LUNCHBOX_RNG_H
Basic type definitions not provided by the operating system.
A random number generator.
Definition: rng.h:43
Abstraction layer and common utilities for multi-threaded programming.
Definition: algorithm.h:29
T get()
Generate a random number.
Definition: rng.h:61