2 staff-symbol-referencer.cc -- implement Staff_symbol_referencer
4 source file of the GNU LilyPond music typesetter
6 (c) 1999--2007 Han-Wen Nienhuys <hanwen@xs4all.nl>
9 #include "staff-symbol-referencer.hh"
11 #include "staff-symbol.hh"
13 #include "output-def.hh"
14 #include "libc-extension.hh"
17 Staff_symbol_referencer::line_count (Grob
*me
)
19 Grob
*st
= get_staff_symbol (me
);
20 return st
? Staff_symbol::line_count (st
) : 0;
24 Staff_symbol_referencer::on_line (Grob
*me
, int pos
)
26 Grob
*st
= get_staff_symbol (me
);
27 return st
? Staff_symbol::on_line (st
, pos
) : false;
31 Staff_symbol_referencer::on_staff_line (Grob
*me
, int pos
)
33 return on_line (me
, pos
) && abs (pos
) <= 2 * staff_radius (me
);
37 Staff_symbol_referencer::get_staff_symbol (Grob
*me
)
39 if (Staff_symbol::has_interface (me
))
42 SCM st
= me
->get_object ("staff-symbol");
43 return unsmob_grob (st
);
47 Staff_symbol_referencer::staff_space (Grob
*me
)
49 Grob
*st
= get_staff_symbol (me
);
51 return Staff_symbol::staff_space (st
);
56 Staff_symbol_referencer::line_thickness (Grob
*me
)
58 Grob
*st
= get_staff_symbol (me
);
60 return Staff_symbol::get_line_thickness (st
);
61 return me
->layout ()->get_dimension (ly_symbol2scm ("line-thickness"));
65 Staff_symbol_referencer::get_position (Grob
*me
)
68 Grob
*st
= get_staff_symbol (me
);
69 Grob
*c
= st
? me
->common_refpoint (st
, Y_AXIS
) : 0;
72 Real y
= me
->relative_coordinate (c
, Y_AXIS
)
73 - st
->relative_coordinate (c
, Y_AXIS
);
75 p
+= 2.0 * y
/ Staff_symbol::staff_space (st
);
79 return me
->relative_coordinate (me
->get_parent (Y_AXIS
), Y_AXIS
) * 2;
80 return robust_scm2double (me
->get_property ("staff-position"), p
);
85 Staff_symbol_referencer::extent_in_staff (Grob
*me
)
87 Grob
*st
= get_staff_symbol (me
);
88 Grob
*c
= st
? me
->common_refpoint (st
, Y_AXIS
) : 0;
93 retval
= me
->extent (c
, Y_AXIS
)
94 - st
->relative_coordinate (c
, Y_AXIS
);
101 Staff_symbol_referencer::get_rounded_position (Grob
*me
)
103 return int (rint (get_position (me
)));
106 MAKE_SCHEME_CALLBACK (Staff_symbol_referencer
, callback
, 1);
108 Staff_symbol_referencer::callback (SCM smob
)
110 Grob
*me
= unsmob_grob (smob
);
112 SCM pos
= me
->get_property ("staff-position");
114 if (scm_is_number (pos
))
116 Real space
= Staff_symbol_referencer::staff_space (me
);
117 off
= scm_to_double (pos
) * space
/ 2.0;
120 return scm_from_double (off
);
123 /* This sets the position relative to the center of the staff symbol.
125 The function is hairy, because it can be called in two situations:
127 1. There is no staff yet; we must set staff-position
129 2. There is a staff, and perhaps someone even applied a
130 translate_axis (). Then we must compensate for the translation
132 In either case, we set a callback to be sure that our new position
133 will be extracted from staff-position */
136 Staff_symbol_referencer::set_position (Grob
*me
, Real p
)
138 Grob
*st
= get_staff_symbol (me
);
140 if (st
&& me
->common_refpoint (st
, Y_AXIS
))
142 oldpos
= get_position (me
);
146 Real ss
= Staff_symbol_referencer::staff_space (me
);
147 me
->translate_axis ((p
- oldpos
) * ss
* 0.5, Y_AXIS
);
150 /* Half of the height, in staff space, i.e. 2.0 for a normal staff. */
152 Staff_symbol_referencer::staff_radius (Grob
*me
)
154 return (line_count (me
) - 1) / 2.0;
158 compare_position (Grob
*const &a
, Grob
*const &b
)
160 return sign (Staff_symbol_referencer::get_position ((Grob
*)a
)
161 - Staff_symbol_referencer::get_position ((Grob
*) b
));
165 position_less (Grob
*const &a
, Grob
*const &b
)
167 return Staff_symbol_referencer::get_position (a
)
168 < Staff_symbol_referencer::get_position (b
);
171 ADD_INTERFACE (Staff_symbol_referencer
,
172 "An object whose Y@tie{}position is meant relative to a staff"
173 " symbol. These usually"
174 " have @code{Staff_symbol_referencer::callback} in their"
175 " @code{Y-offset-callbacks}.",