Visual Servoing Platform  version 3.5.1 under development (2022-07-06)
vpEndian.cpp
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30  *
31  * Description:
32  * Functions for correct endianness handling.
33  *
34  *****************************************************************************/
35 
40 #include <stdexcept>
41 #include <visp3/core/vpEndian.h>
42 
43 namespace vpEndian
44 {
49 uint16_t swap16bits(uint16_t val) { return (((val >> 8) & 0x00FF) | ((val << 8) & 0xFF00)); }
50 
55 uint32_t swap32bits(uint32_t val)
56 {
57  return (((val >> 24) & 0x000000FF) | ((val >> 8) & 0x0000FF00) | ((val << 8) & 0x00FF0000) |
58  ((val << 24) & 0xFF000000));
59 }
60 
65 float swapFloat(float f)
66 {
67  union {
68  float f;
69  unsigned char b[4];
70  } dat1, dat2;
71 
72  dat1.f = f;
73  dat2.b[0] = dat1.b[3];
74  dat2.b[1] = dat1.b[2];
75  dat2.b[2] = dat1.b[1];
76  dat2.b[3] = dat1.b[0];
77  return dat2.f;
78 }
79 
84 double swapDouble(double d)
85 {
86  union {
87  double d;
88  unsigned char b[8];
89  } dat1, dat2;
90 
91  dat1.d = d;
92  dat2.b[0] = dat1.b[7];
93  dat2.b[1] = dat1.b[6];
94  dat2.b[2] = dat1.b[5];
95  dat2.b[3] = dat1.b[4];
96  dat2.b[4] = dat1.b[3];
97  dat2.b[5] = dat1.b[2];
98  dat2.b[6] = dat1.b[1];
99  dat2.b[7] = dat1.b[0];
100  return dat2.d;
101 }
102 
108 uint16_t reinterpret_cast_uchar_to_uint16_LE(unsigned char *const ptr)
109 {
110 #ifdef VISP_LITTLE_ENDIAN
111  return *reinterpret_cast<uint16_t *>(ptr);
112 #elif defined(VISP_BIG_ENDIAN)
113  return swap16bits(*reinterpret_cast<uint16_t *>(ptr));
114 #else
115  throw std::runtime_error("Not supported endianness for correct custom reinterpret_cast() function.");
116 #endif
117 }
118 } // namespace vpEndian
VISP_EXPORT float swapFloat(float f)
Definition: vpEndian.cpp:65
VISP_EXPORT uint32_t swap32bits(uint32_t val)
Definition: vpEndian.cpp:55
VISP_EXPORT uint16_t reinterpret_cast_uchar_to_uint16_LE(unsigned char *const ptr)
Definition: vpEndian.cpp:108
VISP_EXPORT double swapDouble(double d)
Definition: vpEndian.cpp:84
VISP_EXPORT uint16_t swap16bits(uint16_t val)
Definition: vpEndian.cpp:49