2003 -> 2004

[lilypond.git] / lily / staff-symbol-referencer.cc

diff --git a/lily/staff-symbol-referencer.cc b/lily/staff-symbol-referencer.cc
index 9b1ae4ad0811e99ace57ff4890d6bd534ce378c6..cfb871d575cb4b8071da5d31f36214643312d5d1 100644 (file)
--- a/lily/staff-symbol-referencer.cc
+++ b/lily/staff-symbol-referencer.cc
@@ -3,7 +3,7 @@
   
   source file of the GNU LilyPond music typesetter
   
-  (c) 1999--2000 Han-Wen Nienhuys <hanwen@cs.uu.nl>
+  (c) 1999--2004 Han-Wen Nienhuys <hanwen@cs.uu.nl>
  */
 
 #include <math.h>
@@ -11,25 +11,20 @@
 #include "staff-symbol-referencer.hh"
 #include "staff-symbol.hh"
 #include "paper-def.hh"
+#include "libc-extension.hh" 
 
-bool
-Staff_symbol_referencer::has_interface (Grob*e)
-{
-  return unsmob_element (e->get_grob_property ("staff-symbol"))
-    || gh_number_p (e->get_grob_property ("staff-position"));
-}
 
 int
 Staff_symbol_referencer::line_count (Grob*me) 
 {
-  Grob *st = staff_symbol_l (me);
+  Grob *st = get_staff_symbol (me);
   return st  ?  Staff_symbol::line_count (st) : 0;
 }
 
 bool
 Staff_symbol_referencer::on_staffline (Grob*me)
 {
-  return on_staffline (me, (int) position_f (me));
+  return on_staffline (me, (int) rint (get_position (me)));
 }
 
 bool
@@ -40,29 +35,37 @@ Staff_symbol_referencer::on_staffline (Grob*me, int pos)
 }
 
 Grob*
-Staff_symbol_referencer::staff_symbol_l (Grob*me) 
+Staff_symbol_referencer::get_staff_symbol (Grob*me) 
 {
   SCM st = me->get_grob_property ("staff-symbol");
-  return unsmob_element(st);
+  return unsmob_grob (st);
 }
 
 Real
 Staff_symbol_referencer::staff_space (Grob*me) 
 {
-  Grob * st = staff_symbol_l (me);
+  Grob * st = get_staff_symbol (me);
   if (st)
     return Staff_symbol::staff_space (st);
 
-  
   return 1.0;
 }
 
+Real
+Staff_symbol_referencer::line_thickness (Grob*me) 
+{
+  Grob * st = get_staff_symbol (me);
+  if (st)
+    return Staff_symbol::get_line_thickness (st);
+
+  return me->get_paper ()->get_realvar (ly_symbol2scm ("linethickness"));
+}
 
 Real
-Staff_symbol_referencer::position_f (Grob*me) 
+Staff_symbol_referencer::get_position (Grob*me) 
 {
   Real p =0.0;
-  Grob * st = staff_symbol_l (me);
+  Grob * st = get_staff_symbol (me);
   Grob * c = st ? me->common_refpoint (st, Y_AXIS) : 0;
   if (st && c)
     {
@@ -70,39 +73,48 @@ Staff_symbol_referencer::position_f (Grob*me)
        - st->relative_coordinate (c, Y_AXIS);
 
       p += 2.0 * y / Staff_symbol::staff_space (st);
+      return p;
     }
-  else
-    {
-      SCM pos = me->get_grob_property ("staff-position");
-      if (gh_number_p (pos))
-       return gh_scm2double (pos);
-    }
-  
-  return  p;
+
+  return robust_scm2double ( me->get_grob_property ("staff-position"), p);
 }
 
 
+LY_DEFINE(ly_grob_staff_position,
+         "ly:grob-staff-position",
+         1, 0,0, (SCM sg),
+         "Return the Y-position of this grob relative to the staff.")
+{
+  Grob * g = unsmob_grob (sg);
+
+  SCM_ASSERT_TYPE (g, sg, SCM_ARG1, __FUNCTION__, "grob");
+  Real pos = Staff_symbol_referencer::get_position (g);
+
+  if (fabs (rint (pos) -pos) < 1e-6) // ugh.
+    return gh_int2scm ((int) my_round (pos));
+  else
+    return gh_double2scm (pos);
+}
+
 
 /*
   should use offset callback!
  */
-MAKE_SCHEME_CALLBACK(Staff_symbol_referencer,callback,2);
+MAKE_SCHEME_CALLBACK (Staff_symbol_referencer,callback,2);
 SCM
-Staff_symbol_referencer::callback (SCM element_smob, SCM )
+Staff_symbol_referencer::callback (SCM element_smob, SCM)
 {
-  Grob *me = unsmob_element (element_smob);
+  Grob *me = unsmob_grob (element_smob);
 
-  
   SCM pos = me->get_grob_property ("staff-position");
   Real off =0.0;
   if (gh_number_p (pos))
     {
       Real space = Staff_symbol_referencer::staff_space (me);
       off = gh_scm2double (pos) * space/2.0;
+      me->set_grob_property ("staff-position", gh_int2scm (0));
     }
 
-  me->set_grob_property ("staff-position", gh_double2scm (0.0));
-
   return gh_double2scm (off);
 }
 
@@ -124,10 +136,10 @@ Staff_symbol_referencer::callback (SCM element_smob, SCM )
 void
 Staff_symbol_referencer::set_position (Grob*me,Real p)
 {
-  Grob * st = staff_symbol_l (me);
-  if (st && me->common_refpoint(st, Y_AXIS))
+  Grob * st = get_staff_symbol (me);
+  if (st && me->common_refpoint (st, Y_AXIS))
     {
-      Real oldpos = position_f (me);
+      Real oldpos = get_position (me);
       me->set_grob_property ("staff-position", gh_double2scm (p - oldpos));
     }
   else
@@ -144,29 +156,25 @@ Staff_symbol_referencer::set_position (Grob*me,Real p)
 }
 
 /*
-  half  of the height, in staff space.
- */
+  Half of the height, in staff space, i.e. 2.0 for a normal staff. 
+*/
 Real
 Staff_symbol_referencer::staff_radius (Grob*me)
 {
-  return  (line_count (me) -1) / 2;
+  return (line_count (me) -1) / 2.0;
 }
 
 
 int
 compare_position (Grob *const  &a, Grob * const &b)
 {
-  return sign (Staff_symbol_referencer::position_f((Grob*)a) - 
-    Staff_symbol_referencer::position_f((Grob*)b));
-}
-
-
-void
-Staff_symbol_referencer::set_interface (Grob * e)
-{
-  if (!gh_number_p (e->get_grob_property ("staff-position")))
-      e->set_grob_property ("staff-position", gh_double2scm (0.0));
-
-  e->add_offset_callback (Staff_symbol_referencer::callback_proc, Y_AXIS);
+  return sign (Staff_symbol_referencer::get_position ((Grob*)a) - 
+    Staff_symbol_referencer::get_position ((Grob*)b));
 }
 
+ADD_INTERFACE (Staff_symbol_referencer,"staff-symbol-referencer-interface",
+  "Object whose Y position is meaning with reference to a staff "
+"symbol. Objects that have this interface should include "
+"Staff_symbol_referencer::callback in their Y-offset-callback. "
+,
+  "staff-position");