eic-opticks/sysrap/SPack.hh

0001 #pragma once
0002
0003 /**
0004 SPack
0005 ======
0006
0007 Static packing/unpacking utilities.
0008
0009
0010 **/
0011
0012
0013 #include <cstddef>
0014 #include <cstdint>
0015
0016 #include "SYSRAP_API_EXPORT.hh"
0017
0018 class SYSRAP_API SPack {
0019      public:
0020         union uif_t {
0021             unsigned u ;
0022             int      i ;
0023             float    f ;
0024         };
0025
0026         union ui16_t {
0027             uint16_t  u ;
0028             int16_t   i ;
0029         };
0030
0031
0032      public:
0033         static bool     IsLittleEndian();
0034         static unsigned Encode(unsigned x, unsigned y, unsigned z, unsigned w);  // values must fit into unsigned char, ie up to  0xff
0035         static void     Decode( const unsigned int value,  unsigned& x, unsigned& y, unsigned& z, unsigned& w );
0036
0037         static unsigned Encode(unsigned char x, unsigned char y, unsigned char z, unsigned char w);
0038         static unsigned Encode(const unsigned char* ptr, const unsigned num);
0039
0040         static void Decode( const unsigned value,  unsigned char& x, unsigned char& y, unsigned char& z, unsigned char& w );
0041         static void Decode( const unsigned value,  unsigned char* ptr, const unsigned num);
0042
0043      public:
0044         static unsigned Encode13(unsigned char c, unsigned int ccc);
0045         static void Decode13( const unsigned int value, unsigned char& c, unsigned int& ccc );
0046
0047      public:
0048         static unsigned Encode22(unsigned a, unsigned b);
0049         static void     Decode22( const unsigned value, unsigned& a, unsigned& b);
0050         static unsigned Decode22a( const unsigned value );
0051         static unsigned Decode22b( const unsigned value );
0052      public:
0053         static unsigned Encode22hilo( int a, int b );
0054         static void     Decode22hilo( const unsigned packed, int& a, int& b );
0055         static int      Decode22hi( const unsigned packed );
0056         static int      Decode22lo( const unsigned packed );
0057      public:
0058         static float int_as_float( const int i );
0059         static int int_from_float( const float f );
0060         static float uint_as_float( const unsigned f );
0061         static unsigned uint_from_float( const float f );
0062
0063         static float unsigned_as_float( const unsigned u ) ;
0064         static unsigned float_as_unsigned( const float f ) ;
0065
0066
0067         template <int NUM_BITS>
0068         static int unsigned_as_int(unsigned value);
0069
0070         static int unsigned_as_int_32(unsigned value);
0071         static int unsigned_as_int_16(unsigned value);
0072
0073         static double unsigned_as_double( const unsigned x, const unsigned y ) ;
0074         static void double_as_unsigned(unsigned& x, unsigned& y, const double d ) ;
0075
0076
0077
0078 };
0079
0080