include/tools/fract.hxx

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  19 #ifndef INCLUDED_TOOLS_FRACT_HXX
  20 #define INCLUDED_TOOLS_FRACT_HXX
  21
  22 #include <sal/types.h>
  23 #include <tools/toolsdllapi.h>
  24 #include <tools/long.hxx>
  25 #include <ostream>
  26 #include <type_traits>
  27
  28 class SvStream;
  29
  30 class SAL_WARN_UNUSED TOOLS_DLLPUBLIC Fraction final
  31 {
  32     /// these two fields form a boost::rational, but I didn't want to put more boost headers into the global space
  33     sal_Int32       mnNumerator = 0;
  34     sal_Int32       mnDenominator = 1;
  35     bool            mbValid = true;
  36 public:
  37                     Fraction() = default;
  38                     Fraction( const Fraction & rFrac ) = default;
  39                     Fraction( Fraction && rFrac ) = default;
  40     explicit        Fraction( double dVal );
  41                     Fraction( double nNum, double nDen );
  42                     Fraction( sal_Int64 nNum, sal_Int64 nDen );
  43                     // just to prevent ambiguity between the sal_Int64 and double constructors
  44                     template<typename T1, typename T2> Fraction(
  45                         T1 nNum, T2 nDen,
  46                         typename std::enable_if<std::is_integral<T1>::value && std::is_integral<T2>::value, int>::type = 0)
  47                         : Fraction( sal_Int64(nNum), sal_Int64(nDen) ) {}
  48
  49     bool            IsValid() const { return mbValid; }
  50
  51     sal_Int32       GetNumerator() const;
  52     sal_Int32       GetDenominator() const;
  53
  54     explicit operator sal_Int32() const;
  55 #if SAL_TYPES_SIZEOFPOINTER == 8
  56     explicit operator ::tools::Long() const { return operator sal_Int32(); }
  57 #endif
  58     explicit operator double() const;
  59
  60     Fraction&       operator=( const Fraction& rfrFrac ) = default;
  61     Fraction&       operator=( Fraction&& rfrFrac ) = default;
  62     Fraction&       operator=( double v ) { return operator=(Fraction(v)); }
  63
  64     Fraction&       operator+=( const Fraction& rfrFrac );
  65     Fraction&       operator-=( const Fraction& rfrFrac );
  66     Fraction&       operator*=( const Fraction& rfrFrac );
  67     Fraction&       operator/=( const Fraction& rfrFrac );
  68     Fraction&       operator+=( double v ) { return operator+=(Fraction(v)); }
  69     Fraction&       operator-=( double v ) { return operator-=(Fraction(v)); }
  70     Fraction&       operator*=( double v ) { return operator*=(Fraction(v)); }
  71     Fraction&       operator/=( double v ) { return operator/=(Fraction(v)); }
  72
  73     void            ReduceInaccurate( unsigned nSignificantBits );
  74
  75     /// Multiply the two fractions represented here and reduce inaccuracy to 32-bits, used by vcl
  76     static Fraction MakeFraction(tools::Long nN1, tools::Long nN2, tools::Long nD1, tools::Long nD2);
  77
  78     // Compute value usable as hash.
  79     size_t GetHashValue() const;
  80
  81     TOOLS_DLLPUBLIC friend Fraction operator+( const Fraction& rVal1, const Fraction& rVal2 );
  82     TOOLS_DLLPUBLIC friend Fraction operator-( const Fraction& rVal1, const Fraction& rVal2 );
  83     TOOLS_DLLPUBLIC friend Fraction operator*( const Fraction& rVal1, const Fraction& rVal2 );
  84     TOOLS_DLLPUBLIC friend Fraction operator/( const Fraction& rVal1, const Fraction& rVal2 );
  85
  86     TOOLS_DLLPUBLIC friend bool operator==( const Fraction& rVal1, const Fraction& rVal2 );
  87     TOOLS_DLLPUBLIC friend bool operator!=( const Fraction& rVal1, const Fraction& rVal2 );
  88     TOOLS_DLLPUBLIC friend bool operator< ( const Fraction& rVal1, const Fraction& rVal2 );
  89     TOOLS_DLLPUBLIC friend bool operator> ( const Fraction& rVal1, const Fraction& rVal2 );
  90     TOOLS_DLLPUBLIC friend bool operator<=( const Fraction& rVal1, const Fraction& rVal2 );
  91     TOOLS_DLLPUBLIC friend bool operator>=( const Fraction& rVal1, const Fraction& rVal2 );
  92 };
  93
  94 TOOLS_DLLPUBLIC Fraction operator+( const Fraction& rVal1, const Fraction& rVal2 );
  95 TOOLS_DLLPUBLIC Fraction operator-( const Fraction& rVal1, const Fraction& rVal2 );
  96 TOOLS_DLLPUBLIC Fraction operator*( const Fraction& rVal1, const Fraction& rVal2 );
  97 TOOLS_DLLPUBLIC Fraction operator/( const Fraction& rVal1, const Fraction& rVal2 );
  98 TOOLS_DLLPUBLIC bool operator !=( const Fraction& rVal1, const Fraction& rVal2 );
  99 TOOLS_DLLPUBLIC bool operator <=( const Fraction& rVal1, const Fraction& rVal2 );
 100 TOOLS_DLLPUBLIC bool operator >=( const Fraction& rVal1, const Fraction& rVal2 );
 101
 102 inline Fraction operator+( double v1, const Fraction& rVal2 ) { return Fraction(v1) + rVal2; }
 103 inline Fraction operator-( double v1, const Fraction& rVal2 ) { return Fraction(v1) - rVal2; }
 104 inline Fraction operator*( double v1, const Fraction& rVal2 ) { return Fraction(v1) * rVal2; }
 105 inline Fraction operator/( double v1, const Fraction& rVal2 ) { return Fraction(v1) / rVal2; }
 106
 107 inline Fraction operator+( const Fraction& rVal1, double v2 ) { return rVal1 + Fraction(v2); }
 108 inline Fraction operator-( const Fraction& rVal1, double v2 ) { return rVal1 - Fraction(v2); }
 109 inline Fraction operator*( const Fraction& rVal1, double v2 ) { return rVal1 * Fraction(v2); }
 110 inline Fraction operator/( const Fraction& rVal1, double v2 ) { return rVal1 / Fraction(v2); }
 111
 112 template<typename charT, typename traits>
 113 inline std::basic_ostream<charT, traits> & operator <<(
 114     std::basic_ostream<charT, traits> & rStream, const Fraction& rFraction)
 115 {
 116     rStream << "(" << rFraction.GetNumerator() << "/" << rFraction.GetDenominator() << ")";
 117     return rStream;
 118 }
 119
 120 #endif
 121
 122 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */