lily/staff-symbol-referencer-scheme.cc

   1 /*
   2   staff-symbol-referencer-scheme.cc -- implement Staff_symbol_referencer bindings
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c) 1999--2009 Han-Wen Nienhuys <hanwen@xs4all.nl>
   7 */
   8
   9 #include "grob.hh"
  10 #include "staff-symbol-referencer.hh"
  11 #include "staff-symbol.hh"
  12 #include "libc-extension.hh"
  13
  14 LY_DEFINE (ly_grob_staff_position, "ly:grob-staff-position",
  15            1, 0, 0, (SCM sg),
  16            "Return the Y-position of @var{sg} relative to the staff.")
  17 {
  18   LY_ASSERT_SMOB (Grob, sg, 1);
  19   Grob *g = unsmob_grob (sg);
  20   Real pos = Staff_symbol_referencer::get_position (g);
  21
  22   if (fabs (rint (pos) -pos) < 1e-6) // ugh.
  23     return scm_from_int ((int) my_round (pos));
  24   else
  25     return scm_from_double (pos);
  26 }
  27
  28 LY_DEFINE (ly_position_on_line_p, "ly:position-on-line?",
  29            2, 0, 0, (SCM sg, SCM spos),
  30            "Return whether @var{pos} is on a line of the staff associated with the the grob @var{sg} (even on an extender line).")
  31 {
  32   LY_ASSERT_SMOB (Grob, sg, 1);
  33   LY_ASSERT_TYPE (scm_is_number, spos, 2);
  34   Grob *g = unsmob_grob (sg);
  35   Grob *st = Staff_symbol_referencer::get_staff_symbol (g);
  36   int pos = scm_to_int (spos);
  37   bool on_line = st ? Staff_symbol::on_line (g, pos) : false;
  38   return scm_from_bool (on_line);
  39 }
  40
  41 LY_DEFINE (ly_staff_symbol_line_thickness, "ly:staff-symbol-line-thickness",
  42            1, 0, 0, (SCM grob),
  43            "Returns the line-thickness of the staff associated with @var{grob}.")
  44 {
  45   LY_ASSERT_SMOB (Grob, grob, 1);
  46   Grob *g = unsmob_grob (grob);
  47   Real thickness = Staff_symbol_referencer::line_thickness (g);
  48   return scm_from_double (thickness);
  49 }