OPIE: noncore/unsupported/qpdf/fixed.h Source File

00001 #ifndef __FIXED_H__
00002 #define __FIXED_H__
00003 
00004 #include <stdlib.h>
00005 #include <iostream>
00006 
00007 #define _GCC_TEMPLATE_BUG_ 1
00008 
00009 template <unsigned int SH> class fixed {
00010 public:
00011         inline fixed ( int i = 0 )      : m_f ( i2f( i ) ) { }
00012         inline fixed ( double d )       : m_f ( d2f( d )) { }
00013         inline fixed ( const fixed &f ) : m_f ( f. m_f ) { }
00014         
00015         inline operator bool ( ) const   { return m_f != 0; }   
00016         inline operator double ( ) const { return f2d( m_f ); }
00017         inline operator float ( ) const  { return (float) f2d( m_f ); }
00018         inline operator int ( ) const    { return (int) f2i( m_f ); }
00019 
00020         inline fixed &operator = ( const fixed &f ) { m_f = f. m_f; return *this; }
00021         inline fixed &operator = ( double d )       { m_f = d2f( d ); return *this; }
00022         inline fixed &operator = ( float f )        { m_f = d2f( f ); return *this; }
00023         inline fixed &operator = ( int i )          { m_f = i2f( i ); return *this; }
00024 
00025         inline fixed &operator += ( const fixed &f ) { m_f += f. m_f; return *this; }
00026         inline fixed &operator -= ( const fixed &f ) { m_f -= f. m_f; return *this; }
00027         inline fixed &operator *= ( const fixed &f ) { m_f = mul ( m_f, f. m_f ); return *this; }
00028         inline fixed &operator /= ( const fixed &f ) { m_f = div ( m_f, f. m_f ); return *this; }
00029 
00030         inline fixed &operator += ( int i ) { m_f += i2f( i ); return *this; }
00031         inline fixed &operator -= ( int i ) { m_f -= i2f( i ); return *this; }
00032         inline fixed &operator *= ( int i ) { m_f *= i; return *this; }
00033         inline fixed &operator /= ( int i ) { m_f /= i; return *this; }
00034 
00035         inline fixed &operator += ( double d ) { m_f += d2f( d ); return *this; }
00036         inline fixed &operator -= ( double d ) { m_f -= d2f( d ); return *this; }
00037         inline fixed &operator *= ( double d ) { m_f = mul ( m_f, d2f( d )); return *this; }
00038         inline fixed &operator /= ( double d ) { m_f = div ( m_f, d2f( d )); return *this; }
00039 
00040         inline fixed operator - ( ) const { return fixed ( -m_f, true ); }
00041 
00042         inline fixed operator + ( const fixed &f ) const { return fixed ( m_f + f. m_f, true ); }
00043         inline fixed operator - ( const fixed &f ) const { return fixed ( m_f - f. m_f, true ); }
00044         inline fixed operator * ( const fixed &f ) const { return fixed ( mul ( m_f, f. m_f ), true ); }
00045         inline fixed operator / ( const fixed &f ) const { return fixed ( div ( m_f, f. m_f ), true ); }
00046 
00047         inline fixed operator + ( double d ) const { return fixed ( m_f + d2f( d ), true ); }
00048         inline fixed operator - ( double d ) const { return fixed ( m_f - d2f( d ), true ); }
00049         inline fixed operator * ( double d ) const { return fixed ( mul ( m_f, d2f( d )), true ); }
00050         inline fixed operator / ( double d ) const { return fixed ( div ( m_f, d2f( d )), true ); }
00051 
00052         inline fixed operator + ( int i ) const { return fixed ( m_f + i2f( i ), true ); }
00053         inline fixed operator - ( int i ) const { return fixed ( m_f - i2f( i ), true ); }
00054         inline fixed operator * ( int i ) const { return fixed ( m_f * i, true ); }
00055         inline fixed operator / ( int i ) const { return fixed ( m_f / i, true ); }
00056 
00057         inline bool operator <  ( const fixed &f ) const { return m_f < f. m_f; }
00058         inline bool operator >  ( const fixed &f ) const { return m_f > f. m_f; }
00059         inline bool operator <= ( const fixed &f ) const { return m_f <= f. m_f; }
00060         inline bool operator >= ( const fixed &f ) const { return m_f >= f. m_f; }
00061         inline bool operator == ( const fixed &f ) const { return m_f == f. m_f; }
00062         inline bool operator != ( const fixed &f ) const { return m_f != f. m_f; }
00063 
00064         inline bool operator <  ( double d ) const { return m_f < d2f( d ); }
00065         inline bool operator >  ( double d ) const { return m_f > d2f( d ); }
00066         inline bool operator <= ( double d ) const { return m_f <= d2f( d ); }
00067         inline bool operator >= ( double d ) const { return m_f >= d2f( d ); }
00068         inline bool operator == ( double d ) const { return m_f == d2f( d ); }
00069         inline bool operator != ( double d ) const { return m_f != d2f( d ); }
00070 
00071         inline bool operator <  ( int i ) const { return m_f < i2f( i ); }
00072         inline bool operator >  ( int i ) const { return m_f > i2f( i ); }
00073         inline bool operator <= ( int i ) const { return m_f <= i2f( i ); }
00074         inline bool operator >= ( int i ) const { return m_f >= i2f( i ); }
00075         inline bool operator == ( int i ) const { return m_f == i2f( i ); }
00076         inline bool operator != ( int i ) const { return m_f != i2f( i ); }
00077 
00078 #if _GCC_TEMPLATE_BUG_
00079 public: 
00080 #else
00081 private:
00082 #endif
00083         typedef int fix_t;
00084 
00085         inline static double f2d ( fix_t f )   { return ((double) f ) / ((double) ( 1 << SH )); }
00086         inline static fix_t  d2f ( double d )  { return (fix_t) ( d * ((double) ( 1 << SH ))); }
00087         
00088         inline static int    f2i ( fix_t f )   { return (int) ( f >> SH ); }
00089         inline static fix_t  i2f ( int i )     { return (fix_t) ( i << SH ); }  
00090         
00091         inline static fix_t mul ( fix_t m1, fix_t m2 )  { return (fix_t) ((((long long int) m1 ) * m2 ) >> SH ); }      
00092         inline static fix_t div ( fix_t d1, fix_t d2 )  { return (fix_t) ((((long long int) d1 ) << SH ) / d2 ); }
00093         
00094         fixed ( fix_t f, bool /*dummy*/ ) : m_f ( f ) { }
00095 
00096         //data
00097         fix_t m_f;
00098 
00099 // friends:             
00100 #if !_GCC_TEMPLATE_BUG_
00101         friend fixed operator + <> ( int i, const fixed &f );
00102         friend fixed operator - <> ( int i, const fixed &f );
00103         friend fixed operator * <> ( int i, const fixed &f );
00104         friend fixed operator / <> ( int i, const fixed &f );
00105 
00106         friend fixed operator + <> ( double d, const fixed &f );
00107         friend fixed operator - <> ( double d, const fixed &f );
00108         friend fixed operator * <> ( double d, const fixed &f );
00109         friend fixed &operator / <> ( double d, const fixed<SH> &f );
00110 
00111         friend bool operator <  <> ( double d, const fixed &f );
00112         friend bool operator >  <> ( double d, const fixed &f );
00113         friend bool operator <= <> ( double d, const fixed &f );
00114         friend bool operator >= <> ( double d, const fixed &f );
00115         friend bool operator == <> ( double d, const fixed &f );
00116         friend bool operator != <> ( double d, const fixed &f );
00117 
00118         friend bool operator <  <> ( int i, const fixed &f );
00119         friend bool operator >  <> ( int i, const fixed &f );
00120         friend bool operator <= <> ( int i, const fixed &f );
00121         friend bool operator >= <> ( int i, const fixed &f );
00122         friend bool operator == <> ( int i, const fixed &f );
00123         friend bool operator != <> ( int i, const fixed &f );
00124         
00125         friend long int lrint ( const fixed &f );
00126         friend fixed sqrt ( const fixed &f );
00127         friend fixed fabs ( const fixed &f );
00128 #endif
00129 };
00130 
00131 
00132 template <unsigned int SH> inline fixed<SH> operator + ( int i, const fixed<SH> &f )  { return fixed<SH> ( fixed<SH>::i2f( i ) + f. m_f, true ); }
00133 template <unsigned int SH> inline fixed<SH> operator - ( int i, const fixed<SH> &f )  { return fixed<SH> ( fixed<SH>::i2f( i ) - f. m_f, true ); }
00134 template <unsigned int SH> inline fixed<SH> operator * ( int i, const fixed<SH> &f )  { return fixed<SH> ( i * f. m_f, true ); }
00135 template <unsigned int SH> inline fixed<SH> operator / ( int i, const fixed<SH> &f )  { return fixed<SH> ( fixed<SH>::div ( fixed<SH>::i2f( i ), f. m_f ), true ); } 
00136 //template <unsigned int SH> inline fixed<SH> operator / ( int i, const fixed<SH> &f )  { return fixed<SH> ( fixed<SH>::i2f ( i / fixed<SH>::f2i ( f. m_f )), true ); } 
00137 
00138 template <unsigned int SH> inline fixed<SH> operator + ( double d, const fixed<SH> &f ) { return fixed<SH> ( fixed<SH>::d2f( d ) + f. m_f, true ); }
00139 template <unsigned int SH> inline fixed<SH> operator - ( double d, const fixed<SH> &f ) { return fixed<SH> ( fixed<SH>::d2f( d ) - f. m_f, true ); }
00140 template <unsigned int SH> inline fixed<SH> operator * ( double d, const fixed<SH> &f ) { return fixed<SH> ( fixed<SH>::mul ( fixed<SH>::d2f( d ), f. m_f ), true ); }
00141 template <unsigned int SH> inline fixed<SH> operator / ( double d, const fixed<SH> &f ) { return fixed<SH> ( fixed<SH>::mul ( fixed<SH>::d2f( d ), f. m_f ), true ); }
00142 
00143 template <unsigned int SH> inline bool operator <  ( double d, const fixed<SH> &f ) { return fixed<SH>::d2f( d ) < f. m_f; }
00144 template <unsigned int SH> inline bool operator >  ( double d, const fixed<SH> &f ) { return fixed<SH>::d2f( d ) > f. m_f; }
00145 template <unsigned int SH> inline bool operator <= ( double d, const fixed<SH> &f ) { return fixed<SH>::d2f( d ) <= f. m_f; }
00146 template <unsigned int SH> inline bool operator >= ( double d, const fixed<SH> &f ) { return fixed<SH>::d2f( d ) >= f. m_f; }
00147 template <unsigned int SH> inline bool operator == ( double d, const fixed<SH> &f ) { return fixed<SH>::d2f( d ) == f. m_f; }
00148 template <unsigned int SH> inline bool operator != ( double d, const fixed<SH> &f ) { return fixed<SH>::d2f( d ) != f. m_f; }
00149 
00150 template <unsigned int SH> inline bool operator <  ( int i, const fixed<SH> &f ) { return fixed<SH>::i2f( i ) < f. m_f; }
00151 template <unsigned int SH> inline bool operator >  ( int i, const fixed<SH> &f ) { return fixed<SH>::i2f( i ) > f. m_f; }
00152 template <unsigned int SH> inline bool operator <= ( int i, const fixed<SH> &f ) { return fixed<SH>::i2f( i ) <= f. m_f; }
00153 template <unsigned int SH> inline bool operator >= ( int i, const fixed<SH> &f ) { return fixed<SH>::i2f( i ) >= f. m_f; }
00154 template <unsigned int SH> inline bool operator == ( int i, const fixed<SH> &f ) { return fixed<SH>::i2f( i ) == f. m_f; }
00155 template <unsigned int SH> inline bool operator != ( int i, const fixed<SH> &f ) { return fixed<SH>::i2f( i ) != f. m_f; }
00156 
00157 template <unsigned int SH> inline long int lrint ( const fixed<SH> &f )
00158 {
00159         return fixed<SH>::f2i (( f. m_f < 0 ) ? f. m_f - ( 1 << ( SH - 1 )) : f. m_f + ( 1 << ( SH - 1 )));
00160 }
00161 
00162 template <unsigned int SH> inline fixed<SH> fabs ( const fixed<SH> &f )
00163 {
00164         return ( f. m_f < 0 ) ? fixed<SH> ( -f. m_f, true ) : f;
00165 }
00166 
00167 // roughly from QPE / qmath.h 
00168 template <unsigned int SH> inline fixed<SH> sqrt ( const fixed<SH> &f )
00169 {
00170         if ( f. m_f <= 0 )
00171                 return fixed<SH> ( 0, true );
00172                 
00173         typename fixed<SH>::fix_t a0 = 0;
00174         typename fixed<SH>::fix_t a1 = f. m_f; // take value as first approximation
00175         
00176         do {
00177                 a0 = a1;
00178                 a1 = ( a0 + fixed<SH>::div ( f. m_f, a0 )) >> 1;
00179         } while ( abs ( fixed<SH>::div ( a1 - a0,  a1 )) > 1 );
00180         
00181         return fixed<SH> ( a1, true );
00182 }
00183 
00184 #if 0 // no std::ostream needed in OPIE
00185 template <unsigned int SH> inline std::ostream &operator << ( std::ostream &o, const fixed<SH> &f )
00186 {
00187         o << double( f );
00188         return o;
00189 }
00190 #endif
00191 
00192 #endif