2 offset.cc -- implement Offset
4 source file of the GNU LilyPond music typesetter
6 (c) 1997--2007 Han-Wen Nienhuys <hanwen@xs4all.nl>
13 Offset::to_string () const
16 s = string (" (") + ::to_string (coordinate_a_[X_AXIS]) + ", "
17 + ::to_string (coordinate_a_[Y_AXIS]) + ")";
23 free bsd fix by John Galbraith
27 complex_multiply (Offset z1, Offset z2)
30 if (!isinf (z2[Y_AXIS]))
32 z[X_AXIS] = z1[X_AXIS] * z2[X_AXIS] - z1[Y_AXIS] * z2[Y_AXIS];
33 z[Y_AXIS] = z1[X_AXIS] * z2[Y_AXIS] + z1[Y_AXIS] * z2[X_AXIS];
39 complex_conjugate (Offset o)
41 o[Y_AXIS] = -o[Y_AXIS];
46 complex_divide (Offset z1, Offset z2)
48 z2 = complex_conjugate (z2);
49 Offset z = complex_multiply (z1, z2);
50 z *= 1 / z2.length ();
55 complex_exp (Offset o)
57 Real s = sin (o[Y_AXIS]);
58 Real c = cos (o[Y_AXIS]);
60 Real r = exp (o[X_AXIS]);
62 return Offset (r * c, r * s);
68 return atan2 (coordinate_a_[Y_AXIS], coordinate_a_[X_AXIS]);
72 Offset::angle_degrees () const
74 return arg () * 180 / M_PI;
77 euclidian vector length / complex modulus
80 Offset::length () const
82 return sqrt (sqr (coordinate_a_[X_AXIS])
83 + sqr (coordinate_a_[Y_AXIS]));
87 Offset::is_sane () const
89 return !isnan (coordinate_a_[X_AXIS])
90 && !isnan (coordinate_a_ [Y_AXIS])
91 && !isinf (coordinate_a_[X_AXIS])
92 && !isinf (coordinate_a_[Y_AXIS]);
96 Offset::direction () const
104 Offset::swapped () const
106 return Offset (coordinate_a_[Y_AXIS], coordinate_a_[X_AXIS]);