lily/hairpin.cc

   1 /*
   2   hairpin.cc -- implement Hairpin
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c)  1997--2001 Han-Wen Nienhuys <hanwen@cs.uu.nl>
   7 */
   8
   9 #include "molecule.hh"
  10 #include "hairpin.hh"
  11 #include "spanner.hh"
  12 #include "font-interface.hh"
  13 #include "dimensions.hh"
  14 #include "paper-def.hh"
  15 #include "debug.hh"
  16 #include "paper-column.hh"
  17
  18 MAKE_SCHEME_CALLBACK (Hairpin, brew_molecule, 1);
  19
  20 SCM
  21 Hairpin::brew_molecule (SCM smob)
  22 {
  23   Grob *me= unsmob_grob (smob);
  24   Spanner *spanner = dynamic_cast<Spanner*> (me);
  25
  26   Real line = me->paper_l ()->get_var ("stafflinethickness");
  27
  28   SCM s = me->get_grob_property ("grow-direction");
  29   if (!isdir_b (s))
  30     {
  31       me->suicide ();
  32       return SCM_EOL;
  33     }
  34
  35   Direction grow_dir = to_dir (s);
  36
  37
  38   /* Ugh, must be same as Text_spanner::brew_molecule.  */
  39   Real padding = gh_scm2double (me->get_grob_property ("if-text-padding"));
  40
  41   Drul_array<bool> broken;
  42   Drul_array<Item*> bounds ;
  43   Direction d = LEFT;
  44   do
  45     {
  46       bounds[d] =spanner->get_bound (d);
  47       broken[d] = bounds[d]->break_status_dir () != CENTER;
  48     }
  49   while (flip (&d) != LEFT);
  50
  51   Grob *common = bounds[LEFT]->common_refpoint (bounds[RIGHT], X_AXIS);
  52   Drul_array<Real> x_points ;
  53
  54   do
  55     {
  56       Item *b = bounds[d];
  57       x_points[d]  = b->relative_coordinate (common, X_AXIS);
  58       if (broken [d])
  59         {
  60           if (d == LEFT)
  61             x_points[d] = b->extent (common,X_AXIS)[RIGHT] ;
  62         }
  63       else
  64         {
  65           if (dynamic_cast<Paper_column*> (b))
  66             {
  67               /*
  68                 If we're hung on a paper column, that means we're not
  69                 adjacent to a text-dynamic, and we may move closer. We
  70                 make the padding a little smaller, here.
  71               */
  72               Interval e =b->extent (common, X_AXIS);
  73               x_points[d] = e.center () - d  * padding /3; // ugh.
  74             }
  75           else
  76             {
  77               Interval e =b->extent (common, X_AXIS);
  78               if (!e.empty_b ())
  79                 x_points[d] = e[-d] - d*padding;
  80             }
  81         }
  82     }
  83   while (flip (&d) != LEFT);
  84
  85
  86   Real width = x_points[RIGHT] - x_points[LEFT];
  87
  88   if (width < 0)
  89     {
  90       warning (_ ((grow_dir < 0) ? "decrescendo too small"
  91                   : "crescendo too small"));
  92       width = 0;
  93     }
  94
  95   bool continued = broken[Direction (-grow_dir)];
  96   Real height = gh_scm2double (me->get_grob_property ("height"));
  97   Real thick = line * gh_scm2double (me->get_grob_property ("thickness"));
  98
  99   Real starth, endh;
 100   if (grow_dir < 0)
 101     {
 102       starth = height;
 103       endh = continued ? height/2 : 0.0;
 104     }
 105   else
 106     {
 107       starth = continued ? height/2 : 0.0;
 108       endh = height;
 109     }
 110
 111   /*
 112     TODO: junk this and, make a general
 113
 114     Lookup::line  (XY1, XY2).
 115   */
 116   SCM hairpin = gh_list (ly_symbol2scm ("hairpin"),
 117                          gh_double2scm (thick),
 118                          gh_double2scm (width),
 119                          gh_double2scm (starth),
 120                          gh_double2scm (endh),
 121                          SCM_UNDEFINED);
 122
 123   /*
 124     We make the hairpin too large in Y direction, so it stays at
 125     proper distance from the staff.
 126   */
 127   Interval yext = 2* height  * Interval (-1,1);
 128   Box b (Interval (0, width), yext);
 129   Molecule mol (b, hairpin);
 130
 131   mol.translate_axis (x_points[LEFT]
 132                       - bounds[LEFT]->relative_coordinate (common, X_AXIS),
 133                       X_AXIS);
 134
 135   return mol.smobbed_copy ();
 136 }
 137
 138
 139