lily/align-interface.cc

   1 /*
   2   align-interface.cc --  implement Align_interface
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c) 2000 Han-Wen Nienhuys <hanwen@cs.uu.nl>
   7
   8  */
   9
  10 #include "align-interface.hh"
  11
  12 #include "score-element.hh"
  13 #include "group-interface.hh"
  14 #include "axis-group-interface.hh"
  15
  16 /*
  17   This callback is set in the children of the align element. It does
  18   not compute anything, but a side effect of a->do_side_processing ()
  19   is that the elements are placed correctly.  */
  20 Real
  21 Align_interface::alignment_callback (Score_element *sc, Axis ax)
  22 {
  23   Score_element * par = sc->parent_l (ax);
  24   if (par && par->get_elt_property ("alignment-done") == SCM_UNDEFINED)
  25     {
  26       Align_interface::do_side_processing (par, ax);
  27     }
  28   return 0.0;
  29 }
  30
  31
  32 Real
  33 Align_interface::center_on_element (Score_element *me, Axis a)
  34 {
  35   Score_element *cent = unsmob_element (me->get_elt_property ("group-center-element"));
  36
  37   if (cent)
  38     {
  39       Real r = cent->relative_coordinate (me,  a);
  40       return -r;
  41     }
  42   return 0;
  43 }
  44
  45 /*
  46   Hairy function to put elements where they should be. Can be tweaked
  47   from the outside by setting minimum-space and extra-space in its
  48   children */
  49 void
  50 Align_interface::do_side_processing (Score_element * me, Axis a)
  51 {
  52   me->set_elt_property ("alignment-done", SCM_BOOL_T);
  53
  54   SCM d =   me->get_elt_property ("stacking-dir");
  55   Direction stacking_dir = gh_number_p(d) ? to_dir (d) : CENTER;
  56   if (!stacking_dir)
  57     stacking_dir = DOWN;
  58
  59
  60   Array<Interval> dims;
  61
  62   Link_array<Score_element> elems;
  63   Link_array<Score_element> all_elts
  64     = Pointer_group_interface__extract_elements (  me, (Score_element*) 0, "elements");
  65   for (int i=0; i < all_elts.size(); i++)
  66     {
  67       Interval y = all_elts[i]->extent(a) + all_elts[i]->relative_coordinate (me, a);
  68       if (!y.empty_b())
  69         {
  70           Score_element *e =dynamic_cast<Score_element*>(all_elts[i]);
  71
  72           // todo: fucks up if item both in Halign & Valign.
  73           SCM min_dims = e->remove_elt_property ("minimum-space");
  74           if (gh_pair_p (min_dims) &&
  75               gh_number_p (gh_car (min_dims))
  76               && gh_number_p (gh_cdr (min_dims)))
  77             {
  78               y.unite (Interval (gh_scm2double (gh_car  (min_dims)),
  79                                  gh_scm2double (gh_cdr (min_dims))));
  80             }
  81
  82           SCM extra_dims = e->remove_elt_property ("extra-space");
  83           if (gh_pair_p (extra_dims) &&
  84               gh_number_p (gh_car (extra_dims))
  85               && gh_number_p (gh_cdr (extra_dims)))
  86             {
  87               y[LEFT] += gh_scm2double (gh_car  (extra_dims));
  88               y[RIGHT] += gh_scm2double (gh_cdr (extra_dims));
  89             }
  90
  91           elems.push (e);
  92           dims.push (y);
  93         }
  94     }
  95
  96
  97   Interval threshold = Interval (0, Interval::infinity ());
  98   SCM thr = me->get_elt_property ("threshold");
  99   if (gh_pair_p (thr))
 100     {
 101       threshold[SMALLER] = gh_scm2double (gh_car (thr));
 102       threshold[BIGGER] = gh_scm2double (gh_cdr (thr));
 103     }
 104
 105   Real where_f=0;
 106   for (int i=0 ;  i < elems.size(); i++)
 107     {
 108       Real dy = - stacking_dir * dims[i][-stacking_dir];
 109       if (i)
 110         dy += stacking_dir * dims[i-1][stacking_dir];
 111
 112       if (i)
 113         {
 114           dy = (dy >? threshold[SMALLER] )
 115             <? threshold[BIGGER];
 116         }
 117
 118       where_f += stacking_dir * dy;
 119       elems[i]->translate_axis (where_f, a);
 120     }
 121 }
 122
 123
 124 Axis
 125 Align_interface::axis (Score_element*me)
 126 {
 127   return  Axis (gh_scm2int (gh_car (me->get_elt_property ("axes"))));
 128 }
 129
 130
 131 /*
 132   should  use generic Scm funcs.
 133  */
 134 int
 135 Align_interface::get_count (Score_element*me,Score_element*s)
 136 {
 137   SCM e = me->get_elt_property ("elements");
 138   int c =0;
 139   while (gh_pair_p (e))
 140     {
 141       if (gh_car (e) == s->self_scm_)
 142         break;
 143       c++;
 144       e = gh_cdr (e);
 145     }
 146   return c;
 147 }
 148
 149 void
 150 Align_interface::add_element (Score_element*me,Score_element* s)
 151 {
 152   s->add_offset_callback (alignment_callback, Align_interface::axis (me));
 153   Axis_group_interface::add_element (me, s);
 154 }
 155
 156
 157 void
 158 Align_interface::set_interface (Score_element*me)
 159 {
 160   me->set_interface (ly_symbol2scm ("align-interface"));
 161
 162   Axis_group_interface::set_interface (me);
 163 }
 164
 165 void
 166 Align_interface::set_axis (Score_element*me,Axis a)
 167 {
 168   Axis_group_interface::set_axes (me, a,a );
 169 }
 170
 171 bool
 172 Align_interface::has_interface (Score_element*me)
 173 {
 174   return me && me->has_interface (ly_symbol2scm ("align-interface"));
 175 }
 176