lily/line-spanner.cc

   1 /*
   2   line-spanner.cc -- implement Line_spanner
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c) 2000 Jan Nieuwenhuizen <janneke@gnu.org>
   7 */
   8
   9 #include "molecule.hh"
  10 #include "item.hh"
  11 #include "spanner.hh"
  12 #include "line-spanner.hh"
  13 #include "paper-def.hh"
  14 #include "paper-column.hh"
  15 #include "staff-symbol-referencer.hh"
  16
  17 SCM
  18 Line_spanner::line_atom (Grob* me, Real dx, Real dy)
  19 {
  20   SCM list = SCM_EOL;
  21   SCM type = me->get_grob_property ("type");
  22   if (gh_symbol_p (type)
  23       && (type == ly_symbol2scm ("line")
  24           || type == ly_symbol2scm ("dashed-line")
  25           || type == ly_symbol2scm ("dotted-line")))
  26     {
  27       Real staff_space = Staff_symbol_referencer::staff_space (me);
  28       Real thick = me->paper_l ()->get_var ("stafflinethickness");
  29
  30       SCM s = me->get_grob_property ("line-thickness");
  31       if (gh_number_p (s))
  32         thick *= gh_scm2double (s);
  33
  34       // maybe these should be in line-thickness?
  35       Real length = staff_space;
  36       s = me->get_grob_property ("dash-length");
  37       if (gh_number_p (s))
  38         length = gh_scm2double (s) * staff_space;
  39
  40       Real period = 2 * length + thick;
  41       s = me->get_grob_property ("dash-period");
  42       if (gh_number_p (s))
  43         period = gh_scm2double (s) * staff_space;
  44
  45       if (type == ly_symbol2scm ("dotted-line"))
  46         length = thick;
  47
  48       if (type == ly_symbol2scm ("line"))
  49         length = period + thick;
  50
  51       Real on = length - thick;
  52       Real off = period - on;
  53
  54       list = gh_list (ly_symbol2scm ("dashed-line"),
  55                       gh_double2scm (thick),
  56                       gh_double2scm (on),
  57                       gh_double2scm (off),
  58                       gh_double2scm (dx),
  59                       gh_double2scm (dy),
  60                       SCM_UNDEFINED);
  61     }
  62   return list;
  63 }
  64
  65 Offset
  66 Line_spanner::get_broken_offset (Grob *me, Direction dir)
  67 {
  68   Spanner *spanner = dynamic_cast<Spanner*> (me);
  69   Item* bound = spanner->get_bound (dir);
  70
  71   if (!bound->break_status_dir ())
  72     {
  73       Grob *common[] = {
  74         bound->common_refpoint (Staff_symbol_referencer::staff_symbol_l (me),
  75                                 X_AXIS),
  76         bound->common_refpoint (Staff_symbol_referencer::staff_symbol_l (me),
  77                                 Y_AXIS)
  78       };
  79
  80       return Offset ( abs (bound->extent (common[X_AXIS], X_AXIS)[-dir]),
  81                       bound->extent (common[Y_AXIS], Y_AXIS).center ());
  82     }
  83   return Offset ();
  84 }
  85
  86 Offset
  87 Line_spanner::broken_trend_offset (Grob *me, Direction dir)
  88 {
  89   /* A broken line-spaner should maintain the same vertical trend
  90      the unbroken line-spanner would have had.
  91      From slur */
  92   Offset o;
  93   if (Spanner *mother =  dynamic_cast<Spanner*> (me->original_l_))
  94     {
  95       for (int i = dir == LEFT ? 0 : mother->broken_into_l_arr_.size () - 1;
  96            dir == LEFT ? i < mother->broken_into_l_arr_.size () : i > 0;
  97            dir == LEFT ? i++ : i--)
  98         {
  99           if (mother->broken_into_l_arr_[i - dir] == me)
 100             {
 101               Grob *neighbour = mother->broken_into_l_arr_[i];
 102               Offset neighbour_o = get_broken_offset (neighbour, dir);
 103               Offset me_o = get_broken_offset (me, -dir);
 104               // Hmm, why not return me_o[X], but recalc in brew_mol?
 105               o = Offset (0,
 106                           (neighbour_o[Y_AXIS]*me_o[X_AXIS]
 107                            - me_o[Y_AXIS]*neighbour_o[X_AXIS]) * dir /
 108                           (me_o[X_AXIS] + neighbour_o[X_AXIS]));
 109               break;
 110             }
 111         }
 112     }
 113   return o;
 114 }
 115
 116
 117 /*
 118   Warning: this thing is a cross-staff object, so it should have empty Y-dimensions.
 119
 120   (If not, you risk that this is called from the staff-alignment
 121   routine, via molecule_extent. At this point, the staffs aren't
 122   separated yet, so it doesn't work cross-staff.
 123
 124 */
 125
 126 MAKE_SCHEME_CALLBACK (Line_spanner, brew_molecule, 1);
 127 SCM
 128 Line_spanner::brew_molecule (SCM smob)
 129 {
 130   Grob *me= unsmob_grob (smob);
 131
 132   Spanner *spanner = dynamic_cast<Spanner*> (me);
 133   Item* bound_drul[] = {
 134     spanner->get_bound (LEFT),
 135     0,
 136     spanner->get_bound (RIGHT)
 137   };
 138
 139   Item** bound = bound_drul + 1;
 140
 141   Grob *common[] = { 0, 0 };
 142   for (Axis a = X_AXIS;  a < NO_AXES; a = Axis (a + 1))
 143     {
 144       common[a] = bound[LEFT]->common_refpoint (bound[RIGHT], a);
 145
 146       if (!common[a])
 147         return SCM_EOL;
 148     }
 149
 150   Real gap = gh_scm2double (me->get_grob_property ("gap"));
 151
 152   Offset dxy ;
 153   Offset my_off;
 154   Offset his_off;
 155
 156   if (bound[LEFT]->break_status_dir () || bound[RIGHT]->break_status_dir ())
 157     /* across line break */
 158     {
 159       Direction broken = bound[LEFT]->break_status_dir () ? LEFT : RIGHT;
 160
 161       dxy[X_AXIS] = bound[RIGHT]->extent (common[X_AXIS], X_AXIS)[LEFT]
 162         - bound[LEFT]->extent (common[X_AXIS], X_AXIS)[RIGHT];
 163
 164       dxy += broken_trend_offset (me, broken);
 165       dxy[X_AXIS] -= 1 * gap;
 166
 167       my_off = Offset (0,
 168                        me->relative_coordinate (common[Y_AXIS], Y_AXIS));
 169
 170       his_off = Offset (0,
 171                         bound[-broken]->relative_coordinate (common[Y_AXIS],
 172                                                              Y_AXIS));
 173
 174       if (broken == LEFT)
 175         {
 176           my_off[Y_AXIS] += dxy[Y_AXIS];
 177         }
 178     }
 179   else
 180     {
 181       dxy[X_AXIS] = bound[RIGHT]->extent (common[X_AXIS], X_AXIS)[LEFT]
 182         - bound[LEFT]->extent (common[X_AXIS], X_AXIS)[RIGHT];
 183       dxy[Y_AXIS] = bound[RIGHT]->extent (common[Y_AXIS], Y_AXIS).center ()
 184         - bound[LEFT]->extent (common[Y_AXIS], Y_AXIS).center ();
 185       dxy[X_AXIS] -= 2 * gap;
 186
 187       my_off = Offset (me->relative_coordinate (common[X_AXIS], X_AXIS),
 188                        me->relative_coordinate (common[Y_AXIS], Y_AXIS));
 189
 190       his_off = Offset (bound[LEFT]->relative_coordinate (common[X_AXIS],
 191                                                           X_AXIS),
 192                         bound[LEFT]->relative_coordinate (common[Y_AXIS],
 193                                                           Y_AXIS));
 194
 195       }
 196   Molecule line;
 197   SCM list = Line_spanner::line_atom (me, dxy[X_AXIS], dxy[Y_AXIS]);
 198
 199   if (list == SCM_EOL)
 200     return SCM_EOL;
 201
 202   Box b (Interval (0, dxy[X_AXIS]), Interval (0, dxy[Y_AXIS]));
 203
 204   line = Molecule (b, list);
 205   line.translate_axis (bound[LEFT]->extent (bound[LEFT], X_AXIS).length (), X_AXIS);
 206
 207   Offset g (gap, 0);
 208   line.translate (g - my_off + his_off);
 209
 210   return line.smobbed_copy ();
 211 }
 212
 213