2 This file is part of LilyPond, the GNU music typesetter.
4 Copyright (C) 2004--2014 Han-Wen Nienhuys <hanwen@xs4all.nl>
6 LilyPond is free software: you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation, either version 3 of the License, or
9 (at your option) any later version.
11 LilyPond is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with LilyPond. If not, see <http://www.gnu.org/licenses/>.
20 #include "self-alignment-interface.hh"
23 #include "note-column.hh"
24 #include "paper-column.hh"
25 #include "pointer-group-interface.hh"
28 MAKE_SCHEME_CALLBACK (Self_alignment_interface, y_aligned_on_self, 1);
30 Self_alignment_interface::y_aligned_on_self (SCM element)
32 return aligned_on_self (unsmob_grob (element), Y_AXIS, false, 0, 0);
35 MAKE_SCHEME_CALLBACK (Self_alignment_interface, x_aligned_on_self, 1);
37 Self_alignment_interface::x_aligned_on_self (SCM element)
39 return aligned_on_self (unsmob_grob (element), X_AXIS, false, 0, 0);
42 MAKE_SCHEME_CALLBACK (Self_alignment_interface, pure_y_aligned_on_self, 3);
44 Self_alignment_interface::pure_y_aligned_on_self (SCM smob, SCM start, SCM end)
46 return aligned_on_self (unsmob_grob (smob), Y_AXIS, true, robust_scm2int (start, 0), robust_scm2int (end, INT_MAX));
50 Self_alignment_interface::aligned_on_self (Grob *me, Axis a, bool pure, int start, int end)
52 SCM sym = (a == X_AXIS) ? ly_symbol2scm ("self-alignment-X")
53 : ly_symbol2scm ("self-alignment-Y");
55 SCM align (me->internal_get_property (sym));
56 if (scm_is_number (align))
58 Interval ext (me->maybe_pure_extent (me, a, pure, start, end));
59 // Empty extent doesn't mean an error - we simply don't align such grobs.
60 // However, empty extent and non-empty stencil would be suspicious.
62 return scm_from_double (- ext.linear_combination (scm_to_double (align)));
63 else if (me->get_stencil ())
64 warning (me->name () + " has empty extent and non-empty stencil.");
66 return scm_from_double (0.0);
70 Self_alignment_interface::centered_on_object (Grob *him, Axis a)
72 return scm_from_double (robust_relative_extent (him, him, a).center ());
75 MAKE_SCHEME_CALLBACK (Self_alignment_interface, centered_on_x_parent, 1);
77 Self_alignment_interface::centered_on_x_parent (SCM smob)
79 return centered_on_object (unsmob_grob (smob)->get_parent (X_AXIS), X_AXIS);
82 MAKE_SCHEME_CALLBACK (Self_alignment_interface, centered_on_note_columns, 1);
84 Self_alignment_interface::centered_on_note_columns (SCM smob)
86 Item *it = unsmob_item (smob)->get_column ();
88 return scm_from_double (0.0);
90 extract_grob_set (it, "elements", elts);
93 for (vsize i = 0; i < elts.size (); i++)
94 if (Note_column::has_interface (elts[i]))
95 centers.add_point (scm_to_double (centered_on_object (elts[i], X_AXIS)));
97 if (centers.is_empty ())
98 return scm_from_double (0.0);
100 return scm_from_double (centers.center ());
103 MAKE_SCHEME_CALLBACK (Self_alignment_interface, centered_on_y_parent, 1);
105 Self_alignment_interface::centered_on_y_parent (SCM smob)
107 return centered_on_object (unsmob_grob (smob)->get_parent (Y_AXIS), Y_AXIS);
110 MAKE_SCHEME_CALLBACK (Self_alignment_interface, x_centered_on_y_parent, 1);
112 Self_alignment_interface::x_centered_on_y_parent (SCM smob)
114 return centered_on_object (unsmob_grob (smob)->get_parent (Y_AXIS), X_AXIS);
117 MAKE_SCHEME_CALLBACK (Self_alignment_interface, aligned_on_x_parent, 1);
119 Self_alignment_interface::aligned_on_x_parent (SCM smob)
121 return aligned_on_parent (unsmob_grob (smob), X_AXIS);
124 MAKE_SCHEME_CALLBACK (Self_alignment_interface, aligned_on_y_parent, 1);
126 Self_alignment_interface::aligned_on_y_parent (SCM smob)
128 return aligned_on_parent (unsmob_grob (smob), Y_AXIS);
132 Self_alignment_interface::aligned_on_parent (Grob *me, Axis a)
134 Grob *him = me->get_parent (a);
135 if (Paper_column::has_interface (him))
136 return scm_from_double (0.0);
138 Interval he = him->extent (him, a);
140 SCM sym = (a == X_AXIS) ? ly_symbol2scm ("self-alignment-X")
141 : ly_symbol2scm ("self-alignment-Y");
142 SCM align_prop (me->internal_get_property (sym));
144 if (!scm_is_number (align_prop))
145 return scm_from_int (0);
148 Real align = scm_to_double (align_prop);
150 Interval ext (me->extent (me, a));
152 // Empty extent doesn't mean an error - we simply don't align such grobs.
153 // However, empty extent and non-empty stencil would be suspicious.
154 if (!ext.is_empty ())
155 x -= ext.linear_combination (align);
156 else if (me->get_stencil ())
157 warning (me->name () + " has empty extent and non-empty stencil.");
159 // See comment above.
161 x += he.linear_combination (align);
162 else if (him->get_stencil ())
163 warning (him->name () + " has empty extent and non-empty stencil.");
165 return scm_from_double (x);
169 Self_alignment_interface::set_center_parent (Grob *me, Axis a)
171 add_offset_callback (me,
172 (a == X_AXIS) ? centered_on_x_parent_proc : centered_on_y_parent_proc,
177 Self_alignment_interface::set_align_self (Grob *me, Axis a)
179 add_offset_callback (me,
180 (a == X_AXIS) ? x_aligned_on_self_proc : y_aligned_on_self_proc,
184 ADD_INTERFACE (Self_alignment_interface,
185 "Position this object on itself and/or on its parent. To this"
186 " end, the following functions are provided:\n"
189 "@item Self_alignment_interface::[xy]_aligned_on_self\n"
190 "Align self on reference point, using"
191 " @code{self-alignment-X} and @code{self-alignment-Y}."
192 "@item Self_alignment_interface::aligned_on_[xy]_parent\n"
193 "@item Self_alignment_interface::centered_on_[xy]_parent\n"
194 "Shift the object so its own reference point is centered on"
195 " the extent of the parent\n"