lily/vertical-align-engraver.cc

   1 /*
   2   This file is part of LilyPond, the GNU music typesetter.
   3
   4   Copyright (C) 1997--2011 Han-Wen Nienhuys <hanwen@xs4all.nl>
   5
   6   LilyPond is free software: you can redistribute it and/or modify
   7   it under the terms of the GNU General Public License as published by
   8   the Free Software Foundation, either version 3 of the License, or
   9   (at your option) any later version.
  10
  11   LilyPond is distributed in the hope that it will be useful,
  12   but WITHOUT ANY WARRANTY; without even the implied warranty of
  13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14   GNU General Public License for more details.
  15
  16   You should have received a copy of the GNU General Public License
  17   along with LilyPond.  If not, see <http://www.gnu.org/licenses/>.
  18 */
  19
  20 #include "context.hh"
  21 #include "paper-column.hh"
  22 #include "align-interface.hh"
  23 #include "span-bar.hh"
  24 #include "axis-group-interface.hh"
  25 #include "engraver.hh"
  26 #include "spanner.hh"
  27 #include "pointer-group-interface.hh"
  28 #include "grob-array.hh"
  29
  30 #include "translator.icc"
  31
  32 class Vertical_align_engraver : public Engraver
  33 {
  34   Spanner *valign_;
  35   bool qualifies (Grob_info) const;
  36   SCM id_to_group_hashtab_;
  37
  38 public:
  39   TRANSLATOR_DECLARATIONS (Vertical_align_engraver);
  40   DECLARE_ACKNOWLEDGER (axis_group);
  41
  42 protected:
  43   virtual void derived_mark () const;
  44   void process_music ();
  45   virtual void finalize ();
  46   virtual void initialize ();
  47
  48   bool top_level_;
  49 };
  50
  51 ADD_ACKNOWLEDGER (Vertical_align_engraver, axis_group);
  52 ADD_TRANSLATOR (Vertical_align_engraver,
  53                 /* doc */
  54                 "Catch groups (staves, lyrics lines, etc.) and stack them"
  55                 " vertically.",
  56
  57                 /* create */
  58                 "VerticalAlignment ",
  59
  60                 /* read */
  61                 "alignAboveContext "
  62                 "alignBelowContext ",
  63
  64                 /* write */
  65                 ""
  66                 );
  67
  68 Vertical_align_engraver::Vertical_align_engraver ()
  69 {
  70   valign_ = 0;
  71   id_to_group_hashtab_ = SCM_EOL;
  72   top_level_ = false;
  73 }
  74
  75 void
  76 Vertical_align_engraver::derived_mark () const
  77 {
  78   scm_gc_mark (id_to_group_hashtab_);
  79 }
  80
  81 void
  82 Vertical_align_engraver::initialize ()
  83 {
  84   id_to_group_hashtab_ = scm_c_make_hash_table (11);
  85 }
  86
  87 void
  88 Vertical_align_engraver::process_music ()
  89 {
  90   if (!valign_)
  91     {
  92       top_level_ = to_boolean (get_property ("topLevelAlignment"));
  93
  94       valign_ = make_spanner (top_level_ ? "VerticalAlignment" : "StaffGrouper", SCM_EOL);
  95       valign_->set_bound (LEFT, unsmob_grob (get_property ("currentCommandColumn")));
  96       Align_interface::set_ordered (valign_);
  97     }
  98 }
  99
 100 void
 101 Vertical_align_engraver::finalize ()
 102 {
 103   if (valign_)
 104     {
 105       valign_->set_bound (RIGHT, unsmob_grob (get_property ("currentCommandColumn")));
 106       valign_ = 0;
 107     }
 108 }
 109
 110 bool
 111 Vertical_align_engraver::qualifies (Grob_info i) const
 112 {
 113   int sz = i.origin_contexts ((Translator *)this).size ();
 114
 115   return sz > 0 && Axis_group_interface::has_interface (i.grob ())
 116     && !i.grob ()->get_parent (Y_AXIS)
 117     && !to_boolean (i.grob ()->get_property ("no-alignment"))
 118     && Axis_group_interface::has_axis (i.grob (), Y_AXIS);
 119 }
 120
 121 void
 122 Vertical_align_engraver::acknowledge_axis_group (Grob_info i)
 123 {
 124   if (top_level_ && qualifies (i))
 125     {
 126       string id = i.context ()->id_string ();
 127
 128       scm_hash_set_x (id_to_group_hashtab_, ly_string2scm (id),
 129                       i.grob ()->self_scm ());
 130
 131       SCM before_id = i.context ()->get_property ("alignAboveContext");
 132       SCM after_id = i.context ()->get_property ("alignBelowContext");
 133
 134       SCM before = scm_hash_ref (id_to_group_hashtab_, before_id, SCM_BOOL_F);
 135       SCM after = scm_hash_ref (id_to_group_hashtab_, after_id, SCM_BOOL_F);
 136
 137       Grob *before_grob = unsmob_grob (before);
 138       Grob *after_grob = unsmob_grob (after);
 139
 140       Align_interface::add_element (valign_, i.grob ());
 141
 142       if (before_grob || after_grob)
 143         {
 144           Grob_array *ga = unsmob_grob_array (valign_->get_object ("elements"));
 145           vector<Grob*> &arr = ga->array_reference ();
 146
 147           Grob *added = arr.back ();
 148           arr.pop_back ();
 149           for (vsize i = 0; i < arr.size (); i++)
 150             {
 151               if (arr[i] == before_grob)
 152                 {
 153                   arr.insert (arr.begin () + i, added);
 154                   added->set_property ("staff-affinity", scm_from_int (DOWN));
 155                   break;
 156                 }
 157               else if (arr[i] == after_grob)
 158                 {
 159                   arr.insert (arr.begin () + i + 1, added);
 160                   added->set_property ("staff-affinity", scm_from_int (UP));
 161                   break;
 162                 }
 163             }
 164         }
 165     }
 166   else if (qualifies (i) && !unsmob_grob (i.grob ()->get_object ("staff-grouper")))
 167     {
 168       Pointer_group_interface::add_grob (valign_, ly_symbol2scm ("elements"), i.grob ());
 169       i.grob ()->set_object ("staff-grouper", valign_->self_scm ());
 170     }
 171 }