lily/key-signature-interface.cc

   1 /*
   2   key-item.cc -- implement Key_signature_interface
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c) 1996--2004 Han-Wen Nienhuys <hanwen@cs.uu.nl>
   7
   8   keyplacement by Mats Bengtsson
   9 */
  10
  11 #include "item.hh"
  12
  13 #include "stencil.hh"
  14 #include "paper-def.hh"
  15 #include "font-interface.hh"
  16 #include "staff-symbol-referencer.hh"
  17 #include "lookup.hh"
  18 #include "lily-guile.hh"
  19 #include "lily-proto.hh"
  20 #include "accidental-interface.hh"
  21
  22 struct Key_signature_interface
  23 {
  24   DECLARE_SCHEME_CALLBACK (print, (SCM ));
  25
  26   static bool has_interface (Grob*);
  27 };
  28
  29
  30 /*
  31   FIXME: too much hardcoding here.
  32  */
  33 const int FLAT_TOP_PITCH=2; /* fes,ges,as and bes typeset in lower octave */
  34 const int SHARP_TOP_PITCH=4; /*  ais and bis typeset in lower octave */
  35
  36 /*
  37   TODO: look this up. I'm not sure where the naturals ought to go.
  38  */
  39 const int NATURAL_TOP_PITCH = 4;
  40
  41
  42
  43
  44 /*
  45   FIXME: key-item should just get a list of (position, acc), and leave
  46   the thinking to other parties.
  47
  48   - TODO: put this in Scheme
  49
  50   - lots of values trivially shared (key doesn't change very
  51   often). Compute those once, and use that as cache for the rest.
  52
  53   TODO: can  we do without c0pos? it's partly musical.
  54
  55 */
  56 int
  57 alteration_pos  (SCM what, int alter, int c0p)
  58 {
  59   if (ly_pair_p (what))
  60     return ly_scm2int (ly_car (what)) * 7 + ly_scm2int (ly_cdr (what)) + c0p;
  61
  62   int p = ly_scm2int (what);
  63
  64   // Find the c in the range -4 through 2
  65   int from_bottom_pos = c0p + 4;
  66   from_bottom_pos = from_bottom_pos%7;
  67   from_bottom_pos = (from_bottom_pos + 7)%7; // Precaution to get positive.
  68   int c0 = from_bottom_pos - 4;
  69
  70
  71   if ((alter <0 && ((p>FLAT_TOP_PITCH) || (p+c0>4)) && (p+c0>1))
  72       || (alter >0 && ((p > SHARP_TOP_PITCH) || (p+c0>5)) && (p+c0>2))
  73       || (alter == 0 && ((p > NATURAL_TOP_PITCH) || (p + c0>5)) && (p + c0>2)))
  74     {
  75       p -= 7; /* Typeset below c_position */
  76     }
  77   /* Provide for the four cases in which there's a glitch
  78        it's a hack, but probably not worth
  79        the effort of finding a nicer solution.
  80        --dl. */
  81   if (c0==2 && alter >0 && p==3)
  82     p -= 7;
  83   if (c0==-3 && alter>0 && p==-1)
  84     p += 7;
  85   if (c0==-4 && alter<0 && p==-1)
  86     p += 7;
  87   if (c0==-2 && alter<0 && p==-3)
  88     p += 7;
  89
  90   return p + c0;
  91 }
  92
  93 /*
  94   TODO
  95   - space the `natural' signs wider
  96  */
  97 MAKE_SCHEME_CALLBACK (Key_signature_interface,print,1);
  98 SCM
  99 Key_signature_interface::print (SCM smob)
 100 {
 101   Grob*me =unsmob_grob (smob);
 102
 103   Real inter = Staff_symbol_referencer::staff_space (me)/2.0;
 104
 105   SCM scm_style = me->get_property ("style");
 106   String style;
 107   if (ly_symbol_p (scm_style))
 108     {
 109       style = ly_symbol2string (scm_style);
 110     }
 111   else
 112     {
 113       style = "";
 114     }
 115
 116   SCM newas = me->get_property ("new-accidentals");
 117   Stencil mol;
 118
 119   SCM c0s = me->get_property ("c0-position");
 120   int c0p = 0;
 121   if (ly_number_p (c0s))
 122     c0p = ly_scm2int (c0s);
 123
 124   /*
 125     SCM lists are stacks, so we work from right to left, ending with
 126     the cancellation signature.
 127   */
 128
 129   Font_metric *fm = Font_interface::get_default_font (me);
 130   for (SCM s = newas; ly_pair_p (s); s = ly_cdr (s))
 131     {
 132       int alteration = ly_scm2int (ly_cdar (s));
 133       String font_char =
 134         Accidental_interface::get_fontcharname (style, alteration);
 135       Stencil acc (fm->find_by_name ("accidentals-" + font_char));
 136
 137       if (acc.is_empty ())
 138         {
 139           me->warning (_f ("accidental `%s' not found", font_char));
 140         }
 141       else
 142         {
 143           SCM what = ly_caar (s);
 144           int pos = alteration_pos (what, alteration, c0p);
 145           acc.translate_axis (pos * inter, Y_AXIS);
 146           mol.add_at_edge (X_AXIS, LEFT, acc, 0, 0);
 147         }
 148     }
 149
 150   Item *it = dynamic_cast<Item*> (me) ;
 151   if (it->break_status_dir () != RIGHT)
 152     {
 153       SCM old = me->get_property ("old-accidentals");
 154
 155       /*
 156         Add half a space between  cancellation and key sig.
 157
 158         As suggested by [Ross], p.148.
 159        */
 160       Interval x (0, inter);
 161       Interval y (0,0);
 162
 163       mol.add_at_edge (X_AXIS, LEFT, Lookup::blank (Box (x,y)), 0, 0);
 164
 165       Stencil natural;
 166       if (ly_pair_p (old))
 167         natural=Font_interface::get_default_font (me)->
 168             find_by_name (String ("accidentals-") + style + String ("0"));
 169
 170       for (; ly_pair_p (old); old = ly_cdr (old))
 171         {
 172           SCM found = scm_assoc (ly_caar (old), newas);
 173           if (found == SCM_BOOL_F
 174               || ly_cdr (found) != ly_cdar (old))
 175             {
 176               SCM what = ly_caar (old);
 177               int alteration = 0;
 178               int pos = alteration_pos (what, alteration, c0p);
 179
 180               Stencil m = natural;
 181               m.translate_axis (pos* inter, Y_AXIS);
 182
 183               /*
 184                 The natural sign (unlike flat & sharp)
 185                 has vertical edges on both sides. A little padding is
 186                 needed to prevent collisions.
 187                */
 188               Real padding = 0.1 ;
 189               mol.add_at_edge (X_AXIS, LEFT, m, padding, 0);
 190             }
 191         }
 192     }
 193
 194   mol.align_to (X_AXIS, LEFT);
 195
 196   return mol.smobbed_copy ();
 197 }
 198
 199 ADD_INTERFACE (Key_signature_interface, "key-signature-interface",
 200   "A group of accidentals, to be printed as signature sign.",
 201   "c0-position old-accidentals new-accidentals");