lily/balloon.cc

   1 /*
   2   balloon.cc -- implement Balloon
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c) 2004 Han-Wen Nienhuys <hanwen@cs.uu.nl>
   7 */
   8
   9 #include "text-item.hh"
  10 #include "grob.hh"
  11 #include "line-interface.hh"
  12 #include "lookup.hh"
  13 #include "font-interface.hh"
  14 #include "stencil.hh"
  15 #include "lily-guile.hh"
  16 #include "output-def.hh"
  17 #include "misc.hh"
  18
  19 class Balloon_interface
  20 {
  21 public:
  22   DECLARE_SCHEME_CALLBACK (print, (SCM));
  23   static bool has_interface (Grob*);
  24 };
  25
  26 MAKE_SCHEME_CALLBACK (Balloon_interface, print, 1);
  27 SCM
  28 Balloon_interface::print (SCM smob)
  29 {
  30   Grob *me = unsmob_grob (smob);
  31
  32   SCM cb = me->get_property ("balloon-original-callback");
  33   SCM stil = SCM_EOL;
  34
  35   if (ly_c_procedure_p (cb))
  36     stil = scm_call_1 (cb, smob);
  37
  38   if (!unsmob_stencil (stil))
  39     return stil;
  40
  41   SCM scm_off = me->get_property ("balloon-text-offset");
  42
  43   if (!is_number_pair (scm_off))
  44     return stil;
  45
  46   Offset off = ly_scm2offset (scm_off);
  47   Stencil *s = unsmob_stencil (stil);
  48   Box orig_extent = s->extent_box ();
  49   Box box_extent = orig_extent;
  50
  51   Real w = robust_scm2double (me->get_property ("balloon-padding"), .1);
  52   box_extent.widen (w, w);
  53
  54   // FIXME
  55   Stencil fr = Lookup::frame (box_extent, 0.1, 0.05);
  56
  57   fr.add_stencil (*s);
  58
  59   SCM bt = me->get_property ("balloon-text");
  60   SCM chain = Font_interface::text_font_alist_chain (me);
  61   chain = scm_cons (me->get_property ("balloon-text-props"), chain);
  62
  63   SCM text = Text_item::interpret_markup (me->get_paper ()->self_scm (),
  64                                           chain, bt);
  65
  66   Stencil *text_stil = unsmob_stencil (text);
  67
  68   Offset z1;
  69   for (int i = X_AXIS; i < NO_AXES; i++)
  70     {
  71       Axis a ((Axis)i);
  72       z1[a] = box_extent [a].linear_combination (sign (off[a]));
  73       text_stil->align_to (a, -sign (off[a]));
  74     }
  75
  76   Offset z2 = z1 + off;
  77
  78   fr.add_stencil (Line_interface::line (me, z1, z2));
  79
  80   text_stil->translate (z2);
  81   fr.add_stencil (*text_stil);
  82
  83   fr = Stencil (orig_extent, fr.expr ());
  84   return fr.smobbed_copy ();
  85 }
  86
  87 ADD_INTERFACE (Balloon_interface,"text-balloon-interface",
  88                "A collection of routines to put text balloons around an object.",
  89                "balloon-padding balloon-text-props balloon-text-offset balloon-text balloon-original-callback");
  90