lily/system-start-text.cc

   1 /*
   2   system-start-text.cc -- implement System_start_text
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c) 2006--2009 Han-Wen Nienhuys <hanwen@xs4all.nl>
   7
   8 */
   9
  10 #include "text-interface.hh"
  11 #include "pointer-group-interface.hh"
  12 #include "output-def.hh"
  13 #include "font-interface.hh"
  14 #include "spanner.hh"
  15 #include "stencil.hh"
  16 #include "item.hh"
  17
  18 class System_start_text
  19 {
  20 public:
  21   static Stencil get_stencil (Grob *);
  22   DECLARE_GROB_INTERFACE ();
  23
  24   DECLARE_SCHEME_CALLBACK (print, (SCM));
  25 };
  26
  27 Stencil
  28 System_start_text::get_stencil (Grob *me_grob)
  29 {
  30   Spanner *me = dynamic_cast<Spanner*> (me_grob);
  31   SCM t = me->get_property ("text");
  32   if (me->get_break_index () == 0)
  33     t = me->get_property ("long-text");
  34
  35
  36   SCM chain = Font_interface::text_font_alist_chain (me);
  37
  38   SCM scm_stencil = Text_interface::is_markup (t)
  39     ? Text_interface::interpret_markup (me->layout ()->self_scm (), chain, t)
  40     : SCM_EOL;
  41
  42
  43   if (Stencil *p = unsmob_stencil (scm_stencil))
  44     {
  45       SCM align_y  = me_grob->get_property ("self-alignment-Y");
  46       if (scm_is_number (align_y))
  47         p->align_to (Y_AXIS, robust_scm2double (align_y, 0.0));
  48
  49       /* Horizontal alignment according to the self-alignment-X property
  50        * and indent value. */
  51       Output_def *layout = me_grob->layout ();
  52       Real indent;
  53       if (me->get_break_index () == 0)
  54         indent = robust_scm2double (layout->c_variable ("indent"), 0);
  55       else
  56         indent = robust_scm2double (layout->c_variable ("short-indent"), 0);
  57       Real align_x = robust_scm2double (me->get_property ("self-alignment-X"), 0);
  58       Interval p_extent_x = p->extent (X_AXIS);
  59       Interval padding (0.0, max (0.0, indent - p_extent_x.length ()));
  60       Real right_padding = padding.length () - padding.linear_combination (align_x);
  61       Box box (Interval (p_extent_x[LEFT], p_extent_x[RIGHT] + right_padding),
  62                p->extent (Y_AXIS));
  63       Stencil *aligned_p = new Stencil (box, p->expr ());
  64       return *aligned_p;
  65     }
  66   return Stencil ();
  67 }
  68
  69
  70 MAKE_SCHEME_CALLBACK (System_start_text, print, 1);
  71 SCM
  72 System_start_text::print (SCM smob)
  73 {
  74   Spanner *me = unsmob_spanner (smob);
  75
  76   if (!me->get_bound (LEFT)->break_status_dir ())
  77     {
  78       me->suicide ();
  79       return SCM_EOL;
  80     }
  81
  82   extract_grob_set (me, "elements", all_elts);
  83   vector<Grob*> elts;
  84   for (vsize i = 0; i < all_elts.size (); i++)
  85     if (all_elts[i]->is_live ())
  86       elts.push_back (all_elts[i]);
  87
  88   if (!elts.size ())
  89     {
  90       me->suicide ();
  91       return SCM_EOL;
  92     }
  93
  94   Grob *common = common_refpoint_of_array (elts, me, Y_AXIS);
  95
  96   Interval ext;
  97   for (vsize i = elts.size (); i--;)
  98     {
  99       Spanner *sp = dynamic_cast<Spanner *> (elts[i]);
 100
 101       if (sp
 102           && sp->get_bound (LEFT) == me->get_bound (LEFT))
 103         ext.add_point (sp->relative_coordinate (common, Y_AXIS));
 104     }
 105
 106   Stencil m = get_stencil (me);
 107   if (!ext.is_empty ())
 108     m.translate_axis (ext.center (), Y_AXIS);
 109   return m.smobbed_copy ();
 110 }
 111
 112
 113 ADD_INTERFACE (System_start_text,
 114                "Text in front of the system.",
 115
 116                /* properties */
 117                "text "
 118                "long-text "
 119                "self-alignment-Y "
 120                "self-alignment-X "
 121                );