-#include "side-position-interface.hh"
+/*
+ self-alignment-interface.cc -- implement Self_alignment_interface
+
+ source file of the GNU LilyPond music typesetter
+
+ (c) 2004--2008 Han-Wen Nienhuys <hanwen@xs4all.nl>
+*/
+
+#include "self-alignment-interface.hh"
+
#include "warn.hh"
+#include "paper-column.hh"
+#include "grob.hh"
-/*
- Position centered on parent.
- */
-MAKE_SCHEME_CALLBACK (Self_alignment_interface,centered_on_parent,2);
+MAKE_SCHEME_CALLBACK (Self_alignment_interface, y_aligned_on_self, 1);
SCM
-Self_alignment_interface::centered_on_parent (SCM element_smob, SCM axis)
+Self_alignment_interface::y_aligned_on_self (SCM element)
{
- Grob *me = unsmob_grob (element_smob);
- Axis a = (Axis) gh_scm2int (axis);
- Grob *him = me->get_parent (a);
- Interval he = him->extent (him,a);
-
- return gh_double2scm (he.empty_b () ? 0.0 : he.center ());
+ return aligned_on_self (unsmob_grob (element), Y_AXIS);
+}
+
+MAKE_SCHEME_CALLBACK (Self_alignment_interface, x_aligned_on_self, 1);
+SCM
+Self_alignment_interface::x_aligned_on_self (SCM element)
+{
+ return aligned_on_self (unsmob_grob (element), X_AXIS);
}
+SCM
+Self_alignment_interface::aligned_on_self (Grob *me, Axis a)
+{
+ SCM sym = (a == X_AXIS) ? ly_symbol2scm ("self-alignment-X")
+ : ly_symbol2scm ("self-alignment-Y");
+ SCM align (me->internal_get_property (sym));
+ if (scm_is_number (align))
+ {
+ Interval ext (me->extent (me, a));
+ if (ext.is_empty ())
+ programming_error ("cannot align on self: empty element");
+ else
+ return scm_from_double (- ext.linear_combination (scm_to_double (align)));
+ }
+ return scm_from_double (0.0);
+}
-/**
- callback that centers the element on itself
- Requires that self-alignment-{X,Y} be set.
- */
-MAKE_SCHEME_CALLBACK (Self_alignment_interface,aligned_on_self,2);
SCM
-Self_alignment_interface::aligned_on_self (SCM element_smob, SCM axis)
+Self_alignment_interface::centered_on_object (Grob *him, Axis a)
{
- Grob *me = unsmob_grob (element_smob);
- Axis a = (Axis) gh_scm2int (axis);
- static SCM prop_syms[2];
+ return scm_from_double (robust_relative_extent (him, him, a).center ());
+}
- if (!prop_syms[0])
- {
- prop_syms[X_AXIS] = ly_symbol2scm ("self-alignment-X");
- prop_syms[Y_AXIS] = ly_symbol2scm ("self-alignment-Y");
- }
-
- SCM align (me->internal_get_grob_property (prop_syms[a]));
- if (gh_number_p (align))
- {
- Interval ext (me->extent (me,a));
- if (ext.empty_b ())
- {
- programming_error ("I'm empty. Can't align on self");
- return gh_double2scm (0.0);
- }
- else
- {
- return gh_double2scm (- ext.linear_combination (gh_scm2double (align)));
- }
- }
- else if (unsmob_grob (align))
- {
- return gh_double2scm (- unsmob_grob (align)->relative_coordinate (me, a));
- }
- return gh_double2scm (0.0);
+MAKE_SCHEME_CALLBACK (Self_alignment_interface, centered_on_x_parent, 1);
+SCM
+Self_alignment_interface::centered_on_x_parent (SCM smob)
+{
+ return centered_on_object (unsmob_grob (smob)->get_parent (X_AXIS), X_AXIS);
+}
+
+
+MAKE_SCHEME_CALLBACK (Self_alignment_interface, centered_on_y_parent, 1);
+SCM
+Self_alignment_interface::centered_on_y_parent (SCM smob)
+{
+ return centered_on_object (unsmob_grob (smob)->get_parent (Y_AXIS), Y_AXIS);
+}
+
+
+MAKE_SCHEME_CALLBACK (Self_alignment_interface, x_centered_on_y_parent, 1);
+SCM
+Self_alignment_interface::x_centered_on_y_parent (SCM smob)
+{
+ return centered_on_object (unsmob_grob (smob)->get_parent (Y_AXIS), X_AXIS);
+}
+
+MAKE_SCHEME_CALLBACK (Self_alignment_interface, aligned_on_x_parent,1);
+SCM
+Self_alignment_interface::aligned_on_x_parent (SCM smob)
+{
+ return aligned_on_parent (unsmob_grob (smob), X_AXIS);
+}
+
+MAKE_SCHEME_CALLBACK (Self_alignment_interface, aligned_on_y_parent,1);
+SCM
+Self_alignment_interface::aligned_on_y_parent (SCM smob)
+{
+ return aligned_on_parent (unsmob_grob (smob), Y_AXIS);
+}
+
+SCM
+Self_alignment_interface::aligned_on_parent (Grob *me, Axis a)
+{
+ Grob *him = me->get_parent (a);
+ if (Paper_column::has_interface (him))
+ return scm_from_double (0.0);
+
+ Interval he = him->extent (him, a);
+
+ SCM sym = (a == X_AXIS) ? ly_symbol2scm ("self-alignment-X")
+ : ly_symbol2scm ("self-alignment-Y");
+ SCM align_prop (me->internal_get_property (sym));
+
+ if (!scm_is_number (align_prop))
+ return scm_from_int (0);
+
+ Real x = 0.0;
+ Real align = scm_to_double (align_prop);
+
+ Interval ext (me->extent (me, a));
+ if (ext.is_empty ())
+ programming_error ("cannot align on self: empty element");
+ else
+ x -= ext.linear_combination (align);
+
+ if (!he.is_empty ())
+ x += he.linear_combination (align);
+
+ return scm_from_double (x);
+}
+
+void
+Self_alignment_interface::set_center_parent (Grob *me, Axis a)
+{
+ add_offset_callback (me,
+ (a==X_AXIS) ? centered_on_x_parent_proc : centered_on_y_parent_proc,
+ a);
+}
+
+void
+Self_alignment_interface::set_align_self (Grob *me, Axis a)
+{
+ add_offset_callback (me,
+ (a==X_AXIS) ? x_aligned_on_self_proc : y_aligned_on_self_proc,
+ a);
}
+ADD_INTERFACE (Self_alignment_interface,
+ "Position this object on itself and/or on its parent. To this"
+ " end, the following functions are provided:\n"
+ "\n"
+ "@table @code\n"
+ "@item Self_alignment_interface::[xy]_aligned_on_self\n"
+ "Align self on reference point, using"
+ " @code{self-alignment-X} and @code{self-alignment-Y}."
+ "@item Self_alignment_interface::aligned_on_[xy]_parent\n"
+ "@item Self_alignment_interface::centered_on_[xy]_parent\n"
+ "Shift the object so its own reference point is centered on"
+ " the extent of the parent\n"
+ "@end table\n",
-ADD_INTERFACE (Self_alignment_interface, "self-alignment-interface",
- "Position self using some alignment",
- "self-alignment-X self-alignment-Y");
+ /* properties */
+ "self-alignment-X "
+ "self-alignment-Y "
+ );