flower/include/offset.hh

   1 /*
   2   offset.hh -- part of GNU LilyPond
   3
   4   (c) 1996--2007 Han-Wen Nienhuys
   5 */
   6
   7 #ifndef OFFSET_HH
   8 #define OFFSET_HH
   9
  10 #include "axis.hh"
  11 #include "std-string.hh"
  12 #include "real.hh"
  13
  14
  15 /*
  16   This is a mixture a 2D vector. Sometimes it can
  17   also be convenient to think of 2D vectors as complex numbers
  18   (ie. x + i y). The naming of some methods reflects that.
  19 */
  20 class Offset
  21 {
  22 public:
  23   Real coordinate_a_[NO_AXES];
  24
  25   Real &operator [] (Axis i)
  26   {
  27     return coordinate_a_[i];
  28   }
  29
  30   Real operator [] (Axis i) const
  31   {
  32     return coordinate_a_[i];
  33   }
  34
  35   Offset &operator += (Offset o)
  36   {
  37     (*this)[X_AXIS] += o[X_AXIS];
  38     (*this)[Y_AXIS] += o[Y_AXIS];
  39     return *this;
  40   }
  41
  42   Offset operator - () const
  43   {
  44     Offset o = *this;
  45
  46     o[X_AXIS] = -o[X_AXIS];
  47     o[Y_AXIS] = -o[Y_AXIS];
  48     return o;
  49   }
  50
  51   Offset &operator -= (Offset o)
  52   {
  53     (*this)[X_AXIS] -= o[X_AXIS];
  54     (*this)[Y_AXIS] -= o[Y_AXIS];
  55
  56     return *this;
  57   }
  58
  59   Offset &scale (Offset o)
  60   {
  61     (*this)[X_AXIS] *= o[X_AXIS];
  62     (*this)[Y_AXIS] *= o[Y_AXIS];
  63
  64     return *this;
  65   }
  66
  67   Offset &operator /= (Real a)
  68   {
  69     (*this) *= 1/a;
  70     return *this;
  71   }
  72
  73   Offset &operator *= (Real a)
  74   {
  75     (*this)[X_AXIS] *= a;
  76     (*this)[Y_AXIS] *= a;
  77
  78     return *this;
  79   }
  80
  81   Offset (Real ix, Real iy)
  82   {
  83     coordinate_a_[X_AXIS] = ix;
  84     coordinate_a_[Y_AXIS] = iy;
  85   }
  86
  87   Offset ()
  88   {
  89     coordinate_a_[X_AXIS] = coordinate_a_[Y_AXIS] = 0.0;
  90   }
  91
  92   string to_string () const;
  93
  94   Offset &mirror (Axis a)
  95   {
  96     coordinate_a_[a] = -coordinate_a_[a];
  97     return *this;
  98   }
  99   Offset direction () const;
 100   Offset swapped () const;
 101
 102   Real arg () const;
 103   Real angle_degrees () const;
 104   Real length () const;
 105   bool is_sane () const;
 106   Offset operator *= (Offset z2);
 107 };
 108
 109 #include "arithmetic-operator.hh"
 110 IMPLEMENT_ARITHMETIC_OPERATOR (Offset, +);
 111 IMPLEMENT_ARITHMETIC_OPERATOR (Offset, -);
 112 IMPLEMENT_ARITHMETIC_OPERATOR (Offset, *);
 113
 114
 115
 116 Offset complex_multiply (Offset, Offset);
 117 Offset complex_divide (Offset, Offset);
 118 Offset complex_exp (Offset);
 119
 120 inline Offset
 121 Offset::operator *= (Offset z2)
 122 {
 123   *this = complex_multiply (*this, z2);
 124   return *this;
 125 }
 126
 127 inline Offset
 128 operator * (Real o1, Offset o2)
 129 {
 130   o2 *= o1;
 131   return o2;
 132 }
 133
 134 inline Offset
 135 operator / (Offset o1, Real a)
 136 {
 137   o1 /= a;
 138   return o1;
 139 }
 140
 141 inline Offset
 142 operator * (Offset o1, Real o2)
 143 {
 144   o1 *= o2;
 145   return o1;
 146 }
 147
 148 inline Offset
 149 mirror (Offset o, Axis a)
 150 {
 151   o.mirror (a);
 152   return o;
 153 }
 154
 155 inline
 156 Real
 157 dot_product (Offset o1, Offset o2)
 158 {
 159   return o1[X_AXIS] * o2[X_AXIS] + o1[Y_AXIS] * o2[Y_AXIS];
 160 }
 161
 162 #endif /* OFFSET_HH */
 163