Source/System/FileIO/OSB/OSGNFIOBitPacker.h

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  38
  39 #ifndef _OSGNFIOBITPACKER_H_
  40 #define _OSGNFIOBITPACKER_H_
  41 #ifdef __sgi
  42 #pragma once
  43 #endif
  44
  45 #include "OSGBaseTypes.h"
  46
  47 #include <vector>
  48
  49 OSG_BEGIN_NAMESPACE
  50
  51 /*! \brief BitPacker class.
  52           packs and unpacks UInt32
  53     \ingroup GrpFileIOOSB
  54     \nohierarchy
  55 */
  56
  57 class BitPacker
  58 {
  59     /*==========================  PUBLIC  =================================*/
  60 public:
  61     /*---------------------------------------------------------------------*/
  62     /*! \name Types                                                        */
  63     /*! \{                                                                 */
  64
  65     typedef std::vector<UInt8> BufferType;
  66
  67     /*! \}                                                                 */
  68     /*---------------------------------------------------------------------*/
  69     /*! \name Constructor                                                  */
  70     /*! \{                                                                 */
  71
  72     BitPacker(UInt32 size, UInt32 max);
  73
  74     /*! \}                                                                 */
  75     /*---------------------------------------------------------------------*/
  76     /*! \name Pack/get                                                     */
  77     /*! \{                                                                 */
  78
  79     void pack(UInt32 value);
  80
  81     const BufferType &getBuffer(void) const;
  82           BufferType &getBuffer(void);
  83
  84     /*! \}                                                                 */
  85     /*==========================  PRIVATE  ================================*/
  86
  87 private:
  88
  89     UInt32     _numBitsToPack;
  90     Int32      _nextBit;
  91     BufferType _buffer;
  92
  93     static const Int32 BITS_PER_WORD;
  94 };
  95
  96 /*! \ingroup GrpFileIOOSB
  97     \nohierarchy
  98  */
  99
 100 class BitUnpacker
 101 {
 102     /*==========================  PUBLIC  =================================*/
 103   public:
 104     /*---------------------------------------------------------------------*/
 105     /*! \name Types                                                        */
 106     /*! \{                                                                 */
 107
 108     typedef std::vector<UInt8> BufferType;
 109
 110     /*! \}                                                                 */
 111     /*---------------------------------------------------------------------*/
 112     /*! \name Constructor                                                  */
 113     /*! \{                                                                 */
 114
 115     BitUnpacker(const BufferType &buffer, UInt32 max);
 116
 117     /*! \}                                                                 */
 118     /*---------------------------------------------------------------------*/
 119     /*! \name Unpack                                                       */
 120     /*! \{                                                                 */
 121
 122     UInt32 unpack(void);
 123
 124     /*! \}                                                                 */
 125     /*==========================  PRIVATE  ================================*/
 126
 127 private:
 128     UInt32            _numBitsToUnpack;
 129     Int32             _numBitsRemaining;
 130     Int32             _nextBit;
 131
 132     const BufferType &_buffer;
 133 };
 134
 135 OSG_END_NAMESPACE
 136
 137 #endif /* _OSGNFIOBITPACKER_H_ */