lily/key-signature-interface.cc

   1 /*
   2   This file is part of LilyPond, the GNU music typesetter.
   3
   4   Copyright (C) 1996--2011 Han-Wen Nienhuys <hanwen@xs4all.nl>
   5
   6   keyplacement by Mats Bengtsson
   7
   8   LilyPond is free software: you can redistribute it and/or modify
   9   it under the terms of the GNU General Public License as published by
  10   the Free Software Foundation, either version 3 of the License, or
  11   (at your option) any later version.
  12
  13   LilyPond is distributed in the hope that it will be useful,
  14   but WITHOUT ANY WARRANTY; without even the implied warranty of
  15   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16   GNU General Public License for more details.
  17
  18   You should have received a copy of the GNU General Public License
  19   along with LilyPond.  If not, see <http://www.gnu.org/licenses/>.
  20 */
  21
  22 #include "accidental-interface.hh"
  23 #include "font-interface.hh"
  24 #include "international.hh"
  25 #include "item.hh"
  26 #include "lookup.hh"
  27 #include "output-def.hh"
  28 #include "staff-symbol-referencer.hh"
  29 #include "rational.hh"
  30
  31 struct Key_signature_interface
  32 {
  33   DECLARE_SCHEME_CALLBACK (print, (SCM));
  34   DECLARE_GROB_INTERFACE ();
  35 };
  36
  37
  38 /*
  39   TODO
  40   - space the `natural' signs wider
  41 */
  42 MAKE_SCHEME_CALLBACK (Key_signature_interface, print, 1);
  43 SCM
  44 Key_signature_interface::print (SCM smob)
  45 {
  46   Item *me = dynamic_cast<Item *> (unsmob_grob (smob));
  47
  48   Real inter = Staff_symbol_referencer::staff_space (me) / 2.0;
  49
  50   Stencil mol;
  51
  52   SCM c0s = me->get_property ("c0-position");
  53
  54   bool is_cancellation = me->internal_has_interface
  55     (ly_symbol2scm ("key-cancellation-interface"));
  56
  57   /*
  58     SCM lists are stacks, so we work from right to left, ending with
  59     the cancellation signature.
  60   */
  61
  62   int last_pos = -1000;
  63   SCM last_glyph_name = SCM_BOOL_F;
  64   SCM padding_pairs = me->get_property ("padding-pairs");
  65
  66   Font_metric *fm = Font_interface::get_default_font (me);
  67   SCM alist = me->get_property ("glyph-name-alist");
  68
  69   for (SCM s = me->get_property ("alteration-alist"); scm_is_pair (s); s = scm_cdr (s))
  70     {
  71       SCM alt = is_cancellation
  72         ? scm_from_int (0)
  73         : scm_cdar (s);
  74
  75       SCM glyph_name_scm = ly_assoc_get (alt, alist, SCM_BOOL_F);
  76       if (!scm_is_string (glyph_name_scm))
  77         {
  78           me->warning (_f ("No glyph found for alteration: %s",
  79                            ly_scm2rational (alt).to_string ().c_str ()));
  80           continue;
  81         }
  82
  83       string glyph_name = ly_scm2string (glyph_name_scm);
  84
  85       Stencil acc (fm->find_by_name (glyph_name));
  86
  87       if (acc.is_empty ())
  88         me->warning (_ ("alteration not found"));
  89       else
  90         {
  91           SCM what = scm_caar (s);
  92
  93           SCM proc = ly_lily_module_constant ("key-signature-interface::alteration-position");
  94
  95           int pos = scm_to_int (scm_call_3 (proc, what, scm_cdar (s), c0s));
  96           acc.translate_axis (pos * inter, Y_AXIS);
  97
  98           /*
  99             The natural sign (unlike flat & sharp)
 100             has vertical edges on both sides. A little padding is
 101             needed to prevent collisions.
 102           */
 103           Real padding = robust_scm2double (me->get_property ("padding"),
 104                                             0.0);
 105           SCM handle = scm_assoc (scm_cons (glyph_name_scm, last_glyph_name),
 106                                   padding_pairs);
 107           if (scm_is_pair (handle))
 108             padding = robust_scm2double (scm_cdr (handle), 0.0);
 109           else if (glyph_name ==  "accidentals.natural"
 110               && last_pos < pos + 2
 111               && last_pos > pos - 6)
 112             padding += 0.3;
 113
 114           mol.add_at_edge (X_AXIS, LEFT, acc, padding);
 115
 116           last_pos = pos;
 117           last_glyph_name = glyph_name_scm;
 118         }
 119     }
 120
 121   mol.align_to (X_AXIS, LEFT);
 122
 123   return mol.smobbed_copy ();
 124 }
 125
 126 ADD_INTERFACE (Key_signature_interface,
 127                "A group of accidentals, to be printed as signature sign.",
 128
 129                /* properties */
 130                "alteration-alist "
 131                "c0-position "
 132                "glyph-name-alist "
 133                "padding "
 134                "padding-pairs "
 135                );