2 self-alignment-interface.cc -- implement Self_alignment_interface
4 source file of the GNU LilyPond music typesetter
6 (c) 2004--2005 Han-Wen Nienhuys <hanwen@xs4all.nl>
9 #include "self-alignment-interface.hh"
12 MAKE_SCHEME_CALLBACK (Self_alignment_interface, y_aligned_on_self, 1);
14 Self_alignment_interface::y_aligned_on_self (SCM element)
16 return aligned_on_self (unsmob_grob (element), Y_AXIS);
19 MAKE_SCHEME_CALLBACK (Self_alignment_interface, x_aligned_on_self, 1);
21 Self_alignment_interface::x_aligned_on_self (SCM element)
23 return aligned_on_self (unsmob_grob (element), X_AXIS);
27 Self_alignment_interface::aligned_on_self (Grob *me, Axis a)
29 SCM sym = (a == X_AXIS) ? ly_symbol2scm ("self-alignment-X")
30 : ly_symbol2scm ("self-alignment-Y");
32 SCM align (me->internal_get_property (sym));
33 if (scm_is_number (align))
35 Interval ext (me->extent (me, a));
37 programming_error ("can't align on self: empty element");
39 return scm_from_double (- ext.linear_combination (scm_to_double (align)));
41 return scm_from_double (0.0);
47 Self_alignment_interface::centered_on_object (Grob *him, Axis a)
49 return scm_from_double (robust_relative_extent (him, him, a).center ());
53 MAKE_SCHEME_CALLBACK (Self_alignment_interface, centered_on_x_parent, 1);
55 Self_alignment_interface::centered_on_x_parent (SCM smob)
57 return centered_on_object (unsmob_grob (smob)->get_parent (X_AXIS), X_AXIS);
61 MAKE_SCHEME_CALLBACK (Self_alignment_interface, centered_on_y_parent, 1);
63 Self_alignment_interface::centered_on_y_parent (SCM smob)
65 return centered_on_object (unsmob_grob (smob)->get_parent (Y_AXIS), Y_AXIS);
69 MAKE_SCHEME_CALLBACK (Self_alignment_interface, x_centered_on_y_parent, 1);
71 Self_alignment_interface::x_centered_on_y_parent (SCM smob)
73 return centered_on_object (unsmob_grob (smob)->get_parent (Y_AXIS), X_AXIS);
76 MAKE_SCHEME_CALLBACK (Self_alignment_interface, aligned_on_x_parent,1);
78 Self_alignment_interface::aligned_on_x_parent (SCM smob)
80 return aligned_on_parent (unsmob_grob (smob), X_AXIS);
83 MAKE_SCHEME_CALLBACK (Self_alignment_interface, aligned_on_y_parent,1);
85 Self_alignment_interface::aligned_on_y_parent (SCM smob)
87 return aligned_on_parent (unsmob_grob (smob), Y_AXIS);
91 Self_alignment_interface::aligned_on_parent (Grob *me, Axis a)
93 Grob *him = me->get_parent (a);
94 Interval he = him->extent (him, a);
96 SCM sym = (a == X_AXIS) ? ly_symbol2scm ("self-alignment-X")
97 : ly_symbol2scm ("self-alignment-Y");
98 SCM align_prop (me->internal_get_property (sym));
100 if (!scm_is_number (align_prop))
101 return scm_from_int (0);
104 Real align = scm_to_double (align_prop);
106 Interval ext (me->extent (me, a));
108 programming_error ("can't align on self: empty element");
110 x -= ext.linear_combination (align);
113 x += he.linear_combination (align);
115 return scm_from_double (x);
119 Self_alignment_interface::set_center_parent (Grob *me, Axis a)
121 add_offset_callback (me,
122 (a==X_AXIS) ? centered_on_x_parent_proc : centered_on_y_parent_proc,
127 Self_alignment_interface::set_align_self (Grob *me, Axis a)
129 add_offset_callback (me,
130 (a==X_AXIS) ? x_aligned_on_self_proc : y_aligned_on_self_proc,
134 ADD_INTERFACE (Self_alignment_interface, "self-alignment-interface",
135 "Position this object on itself and/or on its parent. To this end, the following functions "
138 "@item Self_alignment_interface::[xy]_aligned_on_self\n"
139 " Align self on reference point, using @code{self-alignment-X} and "
140 "@code{self-alignment-Y}."
141 "@item Self_alignment_interface::aligned_on_[xy]_parent\n"
142 "@item Self_alignment_interface::centered_on_[xy]_parent\n"
143 " Shift the object so its own reference point is centered on the "
144 " extent of the parent \n"
152 "self-alignment-Y ");