wxWidgets/include/wx/math.h
Vadim Zeitlin 2ba9007d0e Add wxCHECK_CXX_STD() and use it to test for C++17 and C++20
Unlike direct tests of __cplusplus, using this macro also works with
(recent enough, i.e. MSVS 2015.3 or later) MSVC versions, even if
/Zc:__cplusplus is not used.

This simplifies some checks and makes some other ones (notably the check
for C++20 used before wxALLOW_COMBINING_ENUMS macro definition) work
with MSVC versions with C++20 support as intended.
2022-05-11 16:57:18 +01:00

229 lines
6.1 KiB
C++

/**
* Name: wx/math.h
* Purpose: Declarations/definitions of common math functions
* Author: John Labenski and others
* Modified by:
* Created: 02/02/03
* Copyright: (c) John Labenski
* Licence: wxWindows licence
*/
/* THIS IS A C FILE, DON'T USE C++ FEATURES (IN PARTICULAR COMMENTS) IN IT */
#ifndef _WX_MATH_H_
#define _WX_MATH_H_
#include "wx/defs.h"
#include <math.h>
#ifndef M_PI
#define M_PI 3.1415926535897932384626433832795
#endif
/* Scaling factors for various unit conversions: 1 inch = 2.54 cm */
#ifndef METRIC_CONVERSION_CONSTANT
#define METRIC_CONVERSION_CONSTANT (1/25.4)
#endif
#ifndef mm2inches
#define mm2inches (METRIC_CONVERSION_CONSTANT)
#endif
#ifndef inches2mm
#define inches2mm (1/(mm2inches))
#endif
#ifndef mm2twips
#define mm2twips (METRIC_CONVERSION_CONSTANT*1440)
#endif
#ifndef twips2mm
#define twips2mm (1/(mm2twips))
#endif
#ifndef mm2pt
#define mm2pt (METRIC_CONVERSION_CONSTANT*72)
#endif
#ifndef pt2mm
#define pt2mm (1/(mm2pt))
#endif
#ifdef __cplusplus
#include <cmath>
/*
Things are simple with C++11: we have everything we need in std.
Eventually we will only have this section and not the legacy stuff below.
*/
#if wxCHECK_CXX_STD(201103)
#define wxFinite(x) std::isfinite(x)
#define wxIsNaN(x) std::isnan(x)
#else /* C++98 */
#if defined(__VISUALC__)
#include <float.h>
#define wxFinite(x) _finite(x)
#elif defined(__MINGW64_TOOLCHAIN__) || defined(__clang__)
/*
add more compilers with C99 support here: using C99 isfinite() is
preferable to using BSD-ish finite()
*/
#if defined(_GLIBCXX_CMATH) || defined(_LIBCPP_CMATH)
// these <cmath> headers #undef isfinite
#define wxFinite(x) std::isfinite(x)
#else
#define wxFinite(x) isfinite(x)
#endif
#elif defined(wxNEEDS_STRICT_ANSI_WORKAROUNDS)
wxDECL_FOR_STRICT_MINGW32(int, _finite, (double))
#define wxFinite(x) _finite(x)
#elif ( defined(__GNUG__)||defined(__GNUWIN32__)|| \
defined(__SGI_CC__)||defined(__SUNCC__)||defined(__XLC__)|| \
defined(__HPUX__) ) && ( !defined(wxOSX_USE_IPHONE) || wxOSX_USE_IPHONE == 0 )
#ifdef __SOLARIS__
#include <ieeefp.h>
#endif
#define wxFinite(x) finite(x)
#else
#define wxFinite(x) ((x) == (x))
#endif
#if defined(__VISUALC__)
#define wxIsNaN(x) _isnan(x)
#elif defined(__GNUG__)||defined(__GNUWIN32__)|| \
defined(__SGI_CC__)||defined(__SUNCC__)||defined(__XLC__)|| \
defined(__HPUX__)
#define wxIsNaN(x) isnan(x)
#else
#define wxIsNaN(x) ((x) != (x))
#endif
#endif /* C++11/C++98 */
#ifdef __INTELC__
inline bool wxIsSameDouble(double x, double y)
{
// VZ: this warning, given for operators==() and !=() is not wrong, as ==
// shouldn't be used with doubles, but we get too many of them and
// removing these operators is probably not a good idea
//
// Maybe we should always compare doubles up to some "epsilon" precision
#pragma warning(push)
// floating-point equality and inequality comparisons are unreliable
#pragma warning(disable: 1572)
return x == y;
#pragma warning(pop)
}
#else /* !__INTELC__ */
wxGCC_WARNING_SUPPRESS(float-equal)
inline bool wxIsSameDouble(double x, double y) { return x == y; }
wxGCC_WARNING_RESTORE(float-equal)
#endif /* __INTELC__/!__INTELC__ */
inline bool wxIsNullDouble(double x) { return wxIsSameDouble(x, 0.); }
inline int wxRound(double x)
{
wxASSERT_MSG(x > double(INT_MIN) - 0.5 && x < double(INT_MAX) + 0.5,
"argument out of supported range");
#if wxCHECK_CXX_STD(201103)
return int(std::lround(x));
#elif defined(HAVE_ROUND) || wxCHECK_VISUALC_VERSION(12)
return int(lround(x));
#else
return int(x < 0 ? x - 0.5 : x + 0.5);
#endif
}
inline int wxRound(float x)
{
wxASSERT_MSG(x > float(INT_MIN) && x < float(INT_MAX),
"argument out of supported range");
#if wxCHECK_CXX_STD(201103)
return int(std::lround(x));
#elif defined(HAVE_ROUND) || wxCHECK_VISUALC_VERSION(12)
return int(lroundf(x));
#else
return int(x < 0.0f ? x - 0.5f : x + 0.5f);
#endif
}
inline int wxRound(long double x) { return wxRound(double(x)); }
// For compatibility purposes, make wxRound() work with integer types too, as
// this used to compile with wx 3.0.
#if WXWIN_COMPATIBILITY_3_0
template <typename T>
wxDEPRECATED_MSG("rounding an integer is useless")
inline int wxRound(T x)
{
// We have to disable this warning for the unsigned types. We do handle
// them correctly in this comparison due to "x > 0" below (removing it
// would make this fail for them!).
wxGCC_WARNING_SUPPRESS(sign-compare)
wxASSERT_MSG((x > 0 || x > INT_MIN) && x < INT_MAX,
"argument out of supported range");
wxGCC_WARNING_RESTORE(sign-compare)
return int(x);
}
#endif // WXWIN_COMPATIBILITY_3_0
// Convert between degrees and radians.
inline double wxDegToRad(double deg) { return (deg * M_PI) / 180.0; }
inline double wxRadToDeg(double rad) { return (rad * 180.0) / M_PI; }
// Count trailing zeros.
WXDLLIMPEXP_BASE unsigned int wxCTZ(wxUint32 x);
#endif /* __cplusplus */
#if defined(__WINDOWS__)
#define wxMulDivInt32( a , b , c ) ::MulDiv( a , b , c )
#else
#define wxMulDivInt32( a , b , c ) (wxRound((a)*(((wxDouble)b)/((wxDouble)c))))
#endif
#if wxUSE_APPLE_IEEE
#ifdef __cplusplus
extern "C" {
#endif
/* functions from common/extended.c */
WXDLLIMPEXP_BASE wxFloat64 wxConvertFromIeeeExtended(const wxInt8 *bytes);
WXDLLIMPEXP_BASE void wxConvertToIeeeExtended(wxFloat64 num, wxInt8 *bytes);
/* use wxConvertFromIeeeExtended() and wxConvertToIeeeExtended() instead */
#if WXWIN_COMPATIBILITY_2_8
wxDEPRECATED( WXDLLIMPEXP_BASE wxFloat64 ConvertFromIeeeExtended(const wxInt8 *bytes) );
wxDEPRECATED( WXDLLIMPEXP_BASE void ConvertToIeeeExtended(wxFloat64 num, wxInt8 *bytes) );
#endif
#ifdef __cplusplus
}
#endif
#endif /* wxUSE_APPLE_IEEE */
/* Compute the greatest common divisor of two positive integers */
WXDLLIMPEXP_BASE unsigned int wxGCD(unsigned int u, unsigned int v);
#endif /* _WX_MATH_H_ */