lily/staff-symbol.cc

   1 /*
   2   staff-symbol.cc -- implement Staff_symbol
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c) 1997--2008 Han-Wen Nienhuys <hanwen@xs4all.nl>
   7 */
   8
   9 #include "staff-symbol.hh"
  10
  11 #include "lookup.hh"
  12 #include "dimensions.hh"
  13 #include "output-def.hh"
  14 #include "warn.hh"
  15 #include "item.hh"
  16 #include "staff-symbol-referencer.hh"
  17 #include "spanner.hh"
  18
  19 MAKE_SCHEME_CALLBACK (Staff_symbol, print, 1);
  20
  21 SCM
  22 Staff_symbol::print (SCM smob)
  23 {
  24   Grob *me = unsmob_grob (smob);
  25   Spanner *sp = dynamic_cast<Spanner *> (me);
  26   Grob *common
  27     = sp->get_bound (LEFT)->common_refpoint (sp->get_bound (RIGHT), X_AXIS);
  28
  29   Interval span_points (0, 0);
  30
  31   /*
  32     For raggedright without ragged staves, simply set width to the linewidth.
  33
  34     (ok -- lousy UI, since width is in staff spaces)
  35
  36     --hwn.
  37   */
  38   Real t = me->layout ()->get_dimension (ly_symbol2scm ("line-thickness"));
  39   t *= robust_scm2double (me->get_property ("thickness"), 1.0);
  40
  41   Direction d = LEFT;
  42   do
  43     {
  44       SCM width_scm = me->get_property ("width");
  45       if (d == RIGHT && scm_is_number (width_scm))
  46         {
  47           /*
  48             don't multiply by Staff_symbol_referencer::staff_space (me),
  49             since that would make aligning staff symbols of different sizes to
  50             one right margin hell.
  51           */
  52           span_points[RIGHT] = scm_to_double (width_scm);
  53         }
  54       else
  55         {
  56           Item *x = sp->get_bound (d);
  57
  58           span_points[d] = x->relative_coordinate (common, X_AXIS);
  59           if (!x->break_status_dir ()
  60               && !x->extent (x, X_AXIS).is_empty ())
  61             span_points[d] += x->extent (x, X_AXIS)[d];
  62         }
  63
  64       span_points[d] -= d* t / 2;
  65     }
  66   while (flip (&d) != LEFT);
  67
  68   Stencil m;
  69
  70   SCM line_positions = me->get_property ("line-positions");
  71   Stencil line
  72     = Lookup::horizontal_line (span_points
  73                                -me->relative_coordinate (common, X_AXIS),
  74                                t);
  75
  76   Real space = staff_space (me);
  77   if (scm_is_pair (line_positions))
  78     {
  79       for (SCM s = line_positions; scm_is_pair (s);
  80            s = scm_cdr (s))
  81         {
  82           Stencil b (line);
  83           b.translate_axis (scm_to_double (scm_car (s))
  84                             * 0.5 * space, Y_AXIS);
  85           m.add_stencil (b);
  86         }
  87     }
  88   else
  89     {
  90       int l = Staff_symbol::line_count (me);
  91       Real height = (l - 1) * staff_space (me) / 2;
  92       for (int i = 0; i < l; i++)
  93         {
  94           Stencil b (line);
  95           b.translate_axis (height - i * space, Y_AXIS);
  96           m.add_stencil (b);
  97         }
  98     }
  99   return m.smobbed_copy ();
 100 }
 101
 102
 103 int
 104 Staff_symbol::get_steps (Grob *me)
 105 {
 106   return line_count (me) * 2;
 107 }
 108
 109 int
 110 Staff_symbol::line_count (Grob *me)
 111 {
 112   SCM c = me->get_property ("line-count");
 113   if (scm_is_number (c))
 114     return scm_to_int (c);
 115   else
 116     return 0;
 117 }
 118
 119 Real
 120 Staff_symbol::staff_space (Grob *me)
 121 {
 122   return robust_scm2double (me->get_property ("staff-space"), 1.0);
 123 }
 124
 125 Real
 126 Staff_symbol::get_line_thickness (Grob *me)
 127 {
 128   Real lt = me->layout ()->get_dimension (ly_symbol2scm ("line-thickness"));
 129
 130   return robust_scm2double (me->get_property ("thickness"), 1.0) * lt;
 131 }
 132
 133 Real
 134 Staff_symbol::get_ledger_line_thickness (Grob *me)
 135 {
 136   SCM lt_pair = me->get_property ("ledger-line-thickness");
 137   Offset z = robust_scm2offset (lt_pair, Offset (1.0, 0.1));
 138
 139   return z[X_AXIS] * get_line_thickness (me) + z[Y_AXIS] * staff_space (me);
 140 }
 141
 142 MAKE_SCHEME_CALLBACK (Staff_symbol, height,1);
 143 SCM
 144 Staff_symbol::height  (SCM smob)
 145 {
 146   Grob *me = unsmob_grob (smob);
 147   Real t = me->layout ()->get_dimension (ly_symbol2scm ("line-thickness"));
 148   t *= robust_scm2double (me->get_property ("thickness"), 1.0);
 149
 150   SCM line_positions = me->get_property ("line-positions");
 151
 152   Interval y_ext;
 153   Real space = staff_space (me);
 154   if (scm_is_pair (line_positions))
 155     {
 156       for (SCM s = line_positions; scm_is_pair (s);
 157            s = scm_cdr (s))
 158         y_ext.add_point (scm_to_double (scm_car (s)) * 0.5 * space);
 159     }
 160   else
 161     {
 162       int l = Staff_symbol::line_count (me);
 163       Real height = (l - 1) * staff_space (me) / 2;
 164       y_ext = Interval (-height, height);
 165     }
 166   y_ext.widen (t/2);
 167   return ly_interval2scm (y_ext);
 168 }
 169
 170 bool
 171 Staff_symbol::on_line (Grob *me, int pos)
 172 {
 173   SCM line_positions = me->get_property ("line-positions");
 174   if (scm_is_pair (line_positions))
 175     {
 176       Real min_line = HUGE_VAL;
 177       Real max_line = -HUGE_VAL;
 178       for (SCM s = line_positions; scm_is_pair (s); s = scm_cdr (s))
 179         {
 180           Real current_line = scm_to_double (scm_car (s));
 181           if (pos == current_line)
 182             return true;
 183           if (current_line > max_line)
 184             max_line = current_line;
 185           if (current_line < min_line)
 186             min_line = current_line;
 187
 188         }
 189       if (pos < min_line)
 190         return (( (int) (rint (pos - min_line)) % 2) == 0);
 191       if (pos > max_line)
 192         return (( (int) (rint (pos - max_line)) % 2) == 0);
 193
 194       return false;
 195     }
 196   else
 197     return ((abs (pos + line_count (me)) % 2) == 1);
 198 }
 199
 200 ADD_INTERFACE (Staff_symbol,
 201                "This spanner draws the lines of a staff.  A staff symbol"
 202                " defines a vertical unit, the @emph{staff space}.  Quantities"
 203                " that go by a half staff space are called @emph{positions}."
 204                "  The center (i.e., middle line or space) is position@tie{}0."
 205                " The length of the symbol may be set by hand through the"
 206                " @code{width} property.",
 207
 208                /* properties */
 209                "ledger-line-thickness "
 210                "line-count "
 211                "line-positions "
 212                "staff-space "
 213                "thickness "
 214                "width "
 215                );