MyGUI  3.2.0
MyGUI_Bitwise.h
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1 
6 /*
7  This file is part of MyGUI.
8 
9  MyGUI is free software: you can redistribute it and/or modify
10  it under the terms of the GNU Lesser General Public License as published by
11  the Free Software Foundation, either version 3 of the License, or
12  (at your option) any later version.
13 
14  MyGUI is distributed in the hope that it will be useful,
15  but WITHOUT ANY WARRANTY; without even the implied warranty of
16  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17  GNU Lesser General Public License for more details.
18 
19  You should have received a copy of the GNU Lesser General Public License
20  along with MyGUI. If not, see <http://www.gnu.org/licenses/>.
21 */
22 #ifndef __MYGUI_BITWISE_H__
23 #define __MYGUI_BITWISE_H__
24 
25 #include "MyGUI_Prerequest.h"
26 
27 namespace MyGUI
28 {
29 
30  class Bitwise
31  {
32  public:
35  template<typename Type>
36  static MYGUI_FORCEINLINE Type firstPO2From(Type _value)
37  {
38  --_value;
39  _value |= _value >> 16;
40  _value |= _value >> 8;
41  _value |= _value >> 4;
42  _value |= _value >> 2;
43  _value |= _value >> 1;
44  ++_value;
45  return _value;
46  }
47 
49  template<typename Type>
50  static MYGUI_FORCEINLINE bool isPO2(Type _value)
51  {
52  return (_value & (_value - 1)) == 0;
53  }
54 
58  template<typename Type>
59  static MYGUI_FORCEINLINE size_t getBitShift(Type _mask)
60  {
61  if (_mask == 0)
62  return 0;
63 
64  size_t result = 0;
65  while ((_mask & 1) == 0)
66  {
67  ++result;
68  _mask >>= 1;
69  }
70  return result;
71  }
72  };
73 
74 } // namespace MyGUI
75 
76 #endif // __MYGUI_BITWISE_H__
static __inline size_t getBitShift(Type _mask)
Definition: MyGUI_Bitwise.h:59
static __inline Type firstPO2From(Type _value)
Definition: MyGUI_Bitwise.h:36
static __inline bool isPO2(Type _value)
Definition: MyGUI_Bitwise.h:50
#define MYGUI_FORCEINLINE