2 self-alignment-interface.cc -- implement Self_alignment_interface
4 source file of the GNU LilyPond music typesetter
6 (c) 2004--2006 Han-Wen Nienhuys <hanwen@xs4all.nl>
9 #include "self-alignment-interface.hh"
13 MAKE_SCHEME_CALLBACK (Self_alignment_interface, y_aligned_on_self, 1);
15 Self_alignment_interface::y_aligned_on_self (SCM element)
17 return aligned_on_self (unsmob_grob (element), Y_AXIS);
20 MAKE_SCHEME_CALLBACK (Self_alignment_interface, x_aligned_on_self, 1);
22 Self_alignment_interface::x_aligned_on_self (SCM element)
24 return aligned_on_self (unsmob_grob (element), X_AXIS);
28 Self_alignment_interface::aligned_on_self (Grob *me, Axis a)
30 SCM sym = (a == X_AXIS) ? ly_symbol2scm ("self-alignment-X")
31 : ly_symbol2scm ("self-alignment-Y");
33 SCM align (me->internal_get_property (sym));
34 if (scm_is_number (align))
36 Interval ext (me->extent (me, a));
38 programming_error ("can't align on self: empty element");
40 return scm_from_double (- ext.linear_combination (scm_to_double (align)));
42 return scm_from_double (0.0);
48 Self_alignment_interface::centered_on_object (Grob *him, Axis a)
50 return scm_from_double (robust_relative_extent (him, him, a).center ());
54 MAKE_SCHEME_CALLBACK (Self_alignment_interface, centered_on_x_parent, 1);
56 Self_alignment_interface::centered_on_x_parent (SCM smob)
58 return centered_on_object (unsmob_grob (smob)->get_parent (X_AXIS), X_AXIS);
62 MAKE_SCHEME_CALLBACK (Self_alignment_interface, centered_on_y_parent, 1);
64 Self_alignment_interface::centered_on_y_parent (SCM smob)
66 return centered_on_object (unsmob_grob (smob)->get_parent (Y_AXIS), Y_AXIS);
70 MAKE_SCHEME_CALLBACK (Self_alignment_interface, x_centered_on_y_parent, 1);
72 Self_alignment_interface::x_centered_on_y_parent (SCM smob)
74 return centered_on_object (unsmob_grob (smob)->get_parent (Y_AXIS), X_AXIS);
77 MAKE_SCHEME_CALLBACK (Self_alignment_interface, aligned_on_x_parent,1);
79 Self_alignment_interface::aligned_on_x_parent (SCM smob)
81 return aligned_on_parent (unsmob_grob (smob), X_AXIS);
84 MAKE_SCHEME_CALLBACK (Self_alignment_interface, aligned_on_y_parent,1);
86 Self_alignment_interface::aligned_on_y_parent (SCM smob)
88 return aligned_on_parent (unsmob_grob (smob), Y_AXIS);
92 Self_alignment_interface::aligned_on_parent (Grob *me, Axis a)
94 Grob *him = me->get_parent (a);
95 Interval he = him->extent (him, a);
97 SCM sym = (a == X_AXIS) ? ly_symbol2scm ("self-alignment-X")
98 : ly_symbol2scm ("self-alignment-Y");
99 SCM align_prop (me->internal_get_property (sym));
101 if (!scm_is_number (align_prop))
102 return scm_from_int (0);
105 Real align = scm_to_double (align_prop);
107 Interval ext (me->extent (me, a));
109 programming_error ("can't align on self: empty element");
111 x -= ext.linear_combination (align);
114 x += he.linear_combination (align);
116 return scm_from_double (x);
120 Self_alignment_interface::set_center_parent (Grob *me, Axis a)
122 add_offset_callback (me,
123 (a==X_AXIS) ? centered_on_x_parent_proc : centered_on_y_parent_proc,
128 Self_alignment_interface::set_align_self (Grob *me, Axis a)
130 add_offset_callback (me,
131 (a==X_AXIS) ? x_aligned_on_self_proc : y_aligned_on_self_proc,
135 ADD_INTERFACE (Self_alignment_interface,
136 "Position this object on itself and/or on its parent. To this end, the following functions "
139 "@item Self_alignment_interface::[xy]_aligned_on_self\n"
140 " Align self on reference point, using @code{self-alignment-X} and "
141 "@code{self-alignment-Y}."
142 "@item Self_alignment_interface::aligned_on_[xy]_parent\n"
143 "@item Self_alignment_interface::centered_on_[xy]_parent\n"
144 " Shift the object so its own reference point is centered on the "
145 " extent of the parent \n"
151 "self-alignment-Y ");