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--2001 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 #include <math.h>
  18
  19 SCM
  20 Line_spanner::line_atom (Grob* me, Real dx, Real dy)
  21 {
  22   SCM list = SCM_EOL;
  23   SCM type = me->get_grob_property ("type");
  24   if (gh_symbol_p (type)
  25       && (type == ly_symbol2scm ("line")
  26           || type == ly_symbol2scm ("dashed-line")
  27           || type == ly_symbol2scm ("dotted-line")))
  28     {
  29       Real staff_space = Staff_symbol_referencer::staff_space (me);
  30       Real thick = me->paper_l ()->get_var ("stafflinethickness");
  31
  32       SCM s = me->get_grob_property ("line-thickness");
  33       if (gh_number_p (s))
  34         thick *= gh_scm2double (s);
  35
  36       // maybe these should be in line-thickness?
  37       Real length = staff_space;
  38       s = me->get_grob_property ("dash-length");
  39       if (gh_number_p (s))
  40         length = gh_scm2double (s) * staff_space;
  41
  42       Real period = 2 * length + thick;
  43       s = me->get_grob_property ("dash-period");
  44       if (gh_number_p (s))
  45         period = gh_scm2double (s) * staff_space;
  46
  47       if (type == ly_symbol2scm ("dotted-line"))
  48         length = thick;
  49
  50       if (type == ly_symbol2scm ("line"))
  51         length = period + thick;
  52
  53       Real on = length - thick;
  54       Real off = period - on;
  55
  56       list = gh_list (ly_symbol2scm ("dashed-line"),
  57                       gh_double2scm (thick),
  58                       gh_double2scm (on),
  59                       gh_double2scm (off),
  60                       gh_double2scm (dx),
  61                       gh_double2scm (dy),
  62                       SCM_UNDEFINED);
  63     }
  64   return list;
  65 }
  66
  67 Offset
  68 Line_spanner::get_broken_offset (Grob *me, Direction dir)
  69 {
  70   Spanner *spanner = dynamic_cast<Spanner*> (me);
  71   Item* bound = spanner->get_bound (dir);
  72
  73   if (!bound->break_status_dir ())
  74     {
  75       Grob *common[] = {
  76         bound->common_refpoint (Staff_symbol_referencer::staff_symbol_l (me),
  77                                 X_AXIS),
  78         bound->common_refpoint (Staff_symbol_referencer::staff_symbol_l (me),
  79                                 Y_AXIS)
  80       };
  81
  82       return Offset (abs (bound->extent (common[X_AXIS], X_AXIS)[-dir]),
  83                       bound->extent (common[Y_AXIS], Y_AXIS).center ());
  84     }
  85   return Offset ();
  86 }
  87
  88 Offset
  89 Line_spanner::broken_trend_offset (Grob *me, Direction dir)
  90 {
  91   /* A broken line-spaner should maintain the same vertical trend
  92      the unbroken line-spanner would have had.
  93      From slur */
  94   Offset o;
  95   if (Spanner *mother =  dynamic_cast<Spanner*> (me->original_l_))
  96     {
  97       for (int i = dir == LEFT ? 0 : mother->broken_into_l_arr_.size () - 1;
  98            dir == LEFT ? i < mother->broken_into_l_arr_.size () : i > 0;
  99            dir == LEFT ? i++ : i--)
 100         {
 101           if (mother->broken_into_l_arr_[i - dir] == me)
 102             {
 103               Grob *neighbour = mother->broken_into_l_arr_[i];
 104               Offset neighbour_o = get_broken_offset (neighbour, dir);
 105               Offset me_o = get_broken_offset (me, -dir);
 106               // Hmm, why not return me_o[X], but recalc in brew_mol?
 107               o = Offset (0,
 108  (neighbour_o[Y_AXIS]*me_o[X_AXIS]
 109                            - me_o[Y_AXIS]*neighbour_o[X_AXIS]) * dir /
 110  (me_o[X_AXIS] + neighbour_o[X_AXIS]));
 111               break;
 112             }
 113         }
 114     }
 115   return o;
 116 }
 117
 118
 119 /*
 120   Warning: this thing is a cross-staff object, so it should have empty Y-dimensions.
 121
 122  (If not, you risk that this is called from the staff-alignment
 123   routine, via molecule_extent. At this point, the staffs aren't
 124   separated yet, so it doesn't work cross-staff.
 125
 126 */
 127
 128 MAKE_SCHEME_CALLBACK (Line_spanner, brew_molecule, 1);
 129 SCM
 130 Line_spanner::brew_molecule (SCM smob)
 131 {
 132   Grob *me= unsmob_grob (smob);
 133
 134   Spanner *spanner = dynamic_cast<Spanner*> (me);
 135   Item* bound_drul[] = {
 136     spanner->get_bound (LEFT),
 137     0,
 138     spanner->get_bound (RIGHT)
 139   };
 140
 141   Item** bound = bound_drul + 1;
 142
 143   Grob *common[] = { 0, 0 };
 144   for (Axis a = X_AXIS;  a < NO_AXES; a = Axis (a + 1))
 145     {
 146       common[a] = bound[LEFT]->common_refpoint (bound[RIGHT], a);
 147
 148       if (!common[a])
 149         return SCM_EOL;
 150     }
 151
 152   Real gap = gh_scm2double (me->get_grob_property ("gap"));
 153   Real dist; /*distance between points */
 154
 155   Offset ofxy (gap, 0); /*offset from start point to start of line*/
 156   Offset dxy ;
 157   Offset my_off;
 158   Offset his_off;
 159
 160
 161   if (bound[LEFT]->break_status_dir () || bound[RIGHT]->break_status_dir ())
 162     /* across line break */
 163     {
 164       Direction broken = bound[LEFT]->break_status_dir () ? LEFT : RIGHT;
 165
 166       dxy[X_AXIS] = bound[RIGHT]->extent (common[X_AXIS], X_AXIS)[LEFT]
 167         - bound[LEFT]->extent (common[X_AXIS], X_AXIS)[RIGHT];
 168
 169       dxy += broken_trend_offset (me, broken);
 170       dxy[X_AXIS] -= 1 * gap;
 171
 172       my_off = Offset (0,
 173                        me->relative_coordinate (common[Y_AXIS], Y_AXIS));
 174
 175       his_off = Offset (0,
 176                         bound[-broken]->relative_coordinate (common[Y_AXIS],
 177                                                              Y_AXIS));
 178
 179       if (broken == LEFT)
 180         {
 181           my_off[Y_AXIS] += dxy[Y_AXIS];
 182         }
 183     }
 184   else
 185     {
 186       Real off = gap + ((bound[LEFT]->extent (bound[LEFT], X_AXIS).length ()*3)/4); // distance from center to start of line
 187       dxy[X_AXIS] = bound[RIGHT]->extent (common[X_AXIS], X_AXIS).center ()
 188         - bound[LEFT]->extent (common[X_AXIS], X_AXIS).center ();
 189       dxy[Y_AXIS] = bound[RIGHT]->extent (common[Y_AXIS], Y_AXIS).center ()
 190         - bound[LEFT]->extent (common[Y_AXIS], Y_AXIS).center ();
 191
 192       dist = sqrt (dxy[X_AXIS]*dxy[X_AXIS]+dxy[Y_AXIS]*dxy[Y_AXIS]);
 193       ofxy = dxy* (off/dist);
 194       dxy -= 2*ofxy;
 195
 196       my_off = Offset (me->relative_coordinate (common[X_AXIS], X_AXIS),
 197                        me->relative_coordinate (common[Y_AXIS], Y_AXIS));
 198
 199       his_off = Offset (bound[LEFT]->relative_coordinate (common[X_AXIS],
 200                                                           X_AXIS),
 201                         bound[LEFT]->relative_coordinate (common[Y_AXIS],
 202                                                           Y_AXIS));
 203
 204       }
 205   Molecule line;
 206   SCM list = Line_spanner::line_atom (me, dxy[X_AXIS], dxy[Y_AXIS]);
 207
 208   if (list == SCM_EOL)
 209     return SCM_EOL;
 210
 211   Box b (Interval (0, dxy[X_AXIS]), Interval (0, dxy[Y_AXIS]));
 212
 213   line = Molecule (b, list);
 214   line.translate_axis (bound[LEFT]->extent (bound[LEFT], X_AXIS).length ()/2, X_AXIS);
 215
 216   //Offset g (gap, 0);
 217   line.translate (ofxy - my_off + his_off);
 218
 219   return line.smobbed_copy ();
 220 }
 221
 222