lily/molecule.cc

   1 /*
   2   molecule.cc -- implement Molecule
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c)  1997--2002 Han-Wen Nienhuys <hanwen@cs.uu.nl>
   7 */
   8
   9 #include <math.h>
  10 #include <libc-extension.hh>    // isinf
  11
  12 #include "font-metric.hh"
  13 #include "dimensions.hh"
  14 #include "interval.hh"
  15 #include "string.hh"
  16 #include "molecule.hh"
  17 #include "warn.hh"
  18
  19
  20 #include "ly-smobs.icc"
  21
  22
  23 SCM
  24 Molecule::smobbed_copy () const
  25 {
  26   Molecule * m = new Molecule (*this);
  27
  28   return m->smobbed_self ();
  29 }
  30
  31 Interval
  32 Molecule::extent (Axis a) const
  33 {
  34   return dim_[a];
  35 }
  36
  37 Molecule::Molecule (Box b, SCM func)
  38 {
  39   expr_ = func;
  40   dim_ = b;
  41 }
  42
  43 Molecule::Molecule ()
  44 {
  45   expr_ = SCM_EOL;
  46   set_empty (true);
  47 }
  48
  49 void
  50 Molecule::translate (Offset o)
  51 {
  52   Axis a = X_AXIS;
  53   while (a < NO_AXES)
  54     {
  55       if (abs (o[a]) > 100 CM
  56           || isinf (o[a]) || isnan (o[a]))
  57         {
  58           programming_error ("Improbable offset for translation: setting to zero");
  59           o[a] =  0.0;
  60         }
  61       incr (a);
  62     }
  63
  64   expr_ = scm_list_n (ly_symbol2scm ("translate-molecule"),
  65                    ly_offset2scm (o),
  66                    expr_, SCM_UNDEFINED);
  67   if (!empty_b ())
  68     dim_.translate (o);
  69 }
  70
  71
  72 void
  73 Molecule::translate_axis (Real x,Axis a)
  74 {
  75   Offset o (0,0);
  76   o[a] = x;
  77   translate (o);
  78 }
  79
  80
  81
  82 void
  83 Molecule::add_molecule (Molecule const &m)
  84 {
  85   expr_ = scm_list_n (ly_symbol2scm ("combine-molecule"),
  86                    m.expr_,
  87                    expr_, SCM_UNDEFINED);
  88   dim_.unite (m.dim_);
  89 }
  90
  91 void
  92 Molecule::set_empty (bool e)
  93 {
  94   if (e)
  95     {
  96       dim_[X_AXIS].set_empty ();
  97       dim_[Y_AXIS].set_empty ();
  98     }
  99   else
 100     {
 101       dim_[X_AXIS] = Interval (0,0);
 102       dim_[Y_AXIS] = Interval (0,0);
 103     }
 104 }
 105
 106
 107 void
 108 Molecule::align_to (Axis a, Direction d)
 109 {
 110   if (empty_b())
 111     return ;
 112
 113   Interval i (extent (a));
 114   Real r = (d == CENTER) ? i.center () : i[d];
 115   translate_axis (-r, a);
 116 }
 117
 118 void
 119 Molecule::add_at_edge (Axis a, Direction d, Molecule const &m, Real padding)
 120 {
 121   Real my_extent= empty_b () ? 0.0 : dim_[a][d];
 122   Interval i (m.extent (a));
 123   Real his_extent;
 124   if (i.empty_b ())
 125     {
 126       programming_error ("Molecule::add_at_edge: adding empty molecule.");
 127       his_extent = 0.0;
 128     }
 129   else
 130     his_extent = i[-d];
 131
 132   Real offset = my_extent -  his_extent;
 133   Molecule toadd (m);
 134   toadd.translate_axis (offset + d * padding, a);
 135   add_molecule (toadd);
 136 }
 137
 138 LY_DEFINE(ly_set_molecule_extent_x,"ly-set-molecule-extent!", 3 , 0, 0,
 139           (SCM mol, SCM axis, SCM np),
 140           "Set the extent (@var{extent} must be a pair of numbers) of @var{mol} in
 141 @var{axis} direction (0 or 1 for x- and y-axis respectively).
 142
 143 Note that an extent @code{(A . B)} is an interval and hence @code{A} is
 144 smaller than @code{B}, and is often negative.
 145 5")
 146 {
 147   Molecule* m = unsmob_molecule (mol);
 148   SCM_ASSERT_TYPE (m, mol, SCM_ARG1, __FUNCTION__, "molecule");
 149   SCM_ASSERT_TYPE (ly_axis_p (axis), axis, SCM_ARG2, __FUNCTION__, "axis");
 150   SCM_ASSERT_TYPE (ly_number_pair_p (np), np, SCM_ARG3, __FUNCTION__, "number pair");
 151
 152   Interval iv = ly_scm2interval (np);
 153   m->dim_[Axis (gh_scm2int (axis))] = iv;
 154
 155   return SCM_UNDEFINED;
 156 }
 157
 158 LY_DEFINE(ly_get_molecule_extent,
 159           "ly-get-molecule-extent", 2 , 0, 0,  (SCM mol, SCM axis),
 160           "Return a pair of numbers signifying the extent of @var{mol} in
 161 @var{axis} direction (0 or 1 for x and y axis respectively).
 162 ")
 163 {
 164   Molecule *m = unsmob_molecule (mol);
 165   SCM_ASSERT_TYPE (m, mol, SCM_ARG1, __FUNCTION__, "molecule");
 166   SCM_ASSERT_TYPE (ly_axis_p (axis), axis, SCM_ARG2, __FUNCTION__, "axis");
 167
 168   return ly_interval2scm (m->extent (Axis (gh_scm2int (axis))));
 169 }
 170
 171
 172 LY_DEFINE(ly_molecule_combined_at_edge,
 173           "ly-combine-molecule-at-edge",
 174           5 , 0, 0,  (SCM first, SCM axis, SCM direction,
 175                       SCM second, SCM padding),
 176           "Construct a molecule by putting @var{second} next to
 177 @var{first}. @var{axis} can be 0 (x-axis) or 1 (y-axis), @var{direction} can be
 178 -1 (left or down) or 1 (right or up).  @var{padding} specifies extra
 179 space to add in between measured in global staff space.")
 180
 181 {
 182   Molecule * m1 = unsmob_molecule (first);
 183   Molecule * m2 = unsmob_molecule (second);
 184   Molecule result;
 185
 186
 187   SCM_ASSERT_TYPE(ly_axis_p (axis), axis, SCM_ARG2, __FUNCTION__, "axis");
 188   SCM_ASSERT_TYPE(ly_dir_p (direction), direction, SCM_ARG3, __FUNCTION__, "dir");
 189   SCM_ASSERT_TYPE(gh_number_p (padding), padding, SCM_ARG4, __FUNCTION__, "number");
 190
 191   if (m1)
 192     result = *m1;
 193   if (m2)
 194     result.add_at_edge (Axis (gh_scm2int (axis)), Direction (gh_scm2int (direction)),
 195                         *m2, gh_scm2double (padding));
 196
 197   return result.smobbed_copy ();
 198 }
 199
 200 /*
 201   FIXME: support variable number of arguments "
 202  */
 203 LY_DEFINE(ly_add_molecule ,
 204           "ly-add-molecule", 2, 0,0,(SCM first, SCM second),
 205           "Combine two molecules."
 206           )
 207 {
 208   Molecule * m1 = unsmob_molecule (first);
 209   Molecule * m2 = unsmob_molecule (second);
 210   Molecule result;
 211
 212
 213   if (m1)
 214     result = *m1;
 215   if (m2)
 216     result.add_molecule (*m2);
 217
 218   return result.smobbed_copy ();
 219 }
 220
 221 LY_DEFINE(ly_make_molecule,
 222           "ly-make-molecule", 3, 0, 0,  (SCM expr, SCM xext, SCM yext),
 223           "
 224 The objective of any typesetting system is to put ink on paper in the
 225 right places. For LilyPond, this final stage is left to the @TeX{} and
 226 the printer subsystem. For lily, the last stage in processing a score is
 227 outputting a description of what to put where.  This description roughly
 228 looks like
 229 @example
 230         PUT glyph AT (x,y)
 231         PUT glyph AT (x,y)
 232         PUT glyph AT (x,y)
 233 @end example
 234 you merely have to look at the tex output of lily to see this.
 235 Internally these instructions are encoded in Molecules.@footnote{At some
 236 point LilyPond also contained Atom-objects, but they have been replaced
 237 by Scheme expressions, making the name outdated.}  A molecule is
 238 what-to-print-where information that also contains dimension information
 239 (how large is this glyph?).
 240
 241 Conceptually, Molecules can be constructed from Scheme code, by
 242 translating a Molecule and by combining two molecules. In BNF
 243 notation:
 244
 245 @example
 246 Molecule  :: COMBINE Molecule Molecule
 247            | TRANSLATE Offset Molecule
 248            | GLYPH-DESCRIPTION
 249            ;
 250 @end example
 251
 252 If you are interested in seeing how this information is stored, you
 253 can run with the @code{-f scm} option. The scheme expressions are then
 254 dumped in the output file.")
 255 {
 256   SCM_ASSERT_TYPE (ly_number_pair_p (xext), xext, SCM_ARG2, __FUNCTION__, "number pair");
 257   SCM_ASSERT_TYPE (ly_number_pair_p (yext), yext, SCM_ARG3, __FUNCTION__, "number pair");
 258
 259   Box b (ly_scm2interval (xext), ly_scm2interval(yext));
 260   Molecule m (b, expr);
 261   return m.smobbed_copy ();
 262 }
 263
 264 SCM
 265 fontify_atom (Font_metric const * met, SCM f)
 266 {
 267   if (f == SCM_EOL)
 268     return f;
 269   else
 270     return  scm_list_n (ly_symbol2scm ("fontify"),
 271                         ly_quote_scm (met->description_), f, SCM_UNDEFINED);
 272 }
 273
 274 LY_DEFINE(ly_fontify_atom,"ly-fontify-atom", 2, 0, 0,
 275           (SCM met, SCM f),
 276           "Add a font selection command for the font metric @var{met} to @var{f}.")
 277 {
 278   SCM_ASSERT_TYPE(unsmob_metrics (met), met, SCM_ARG1, __FUNCTION__, "font metric");
 279
 280   return fontify_atom (unsmob_metrics (met), f);
 281 }
 282 LY_DEFINE(ly_align_to_x,"ly-align-to!", 3, 0, 0,  (SCM mol, SCM axis, SCM dir),
 283           "Align @var{mol} using its own extents.")
 284 {
 285   SCM_ASSERT_TYPE(unsmob_molecule (mol), mol, SCM_ARG1, __FUNCTION__, "molecule");
 286   SCM_ASSERT_TYPE(ly_axis_p (axis), axis, SCM_ARG2, __FUNCTION__, "axis");
 287   SCM_ASSERT_TYPE(ly_dir_p (dir), dir, SCM_ARG3, __FUNCTION__, "dir");
 288
 289   unsmob_molecule (mol)->align_to ((Axis)gh_scm2int (axis), Direction (gh_scm2int (dir)));
 290
 291   return SCM_UNDEFINED;
 292 }
 293
 294
 295
 296 /*
 297   Hmm... maybe this is not such a good idea ; stuff can be empty,
 298   while expr_ == '()
 299  */
 300 bool
 301 Molecule::empty_b () const
 302 {
 303   return expr_ == SCM_EOL;
 304 }
 305
 306 SCM
 307 Molecule::get_expr () const
 308 {
 309   return expr_;
 310 }
 311
 312
 313
 314 Box
 315 Molecule::extent_box () const
 316 {
 317   return dim_;
 318 }
 319 IMPLEMENT_SIMPLE_SMOBS (Molecule);
 320
 321
 322 int
 323 Molecule::print_smob (SCM , SCM port, scm_print_state *)
 324 {
 325   scm_puts ("#<Molecule ", port);
 326 #if 0
 327   Molecule  *r = (Molecule *) ly_cdr (s);
 328   String string (r->string ());
 329   scm_puts ((char *)str.to_str0 (), port);
 330 #endif
 331   scm_puts (" >", port);
 332
 333   return 1;
 334 }
 335
 336
 337 SCM
 338 Molecule::mark_smob (SCM s)
 339 {
 340   Molecule  *r = (Molecule *) ly_cdr (s);
 341
 342   return r->expr_;
 343 }
 344
 345 IMPLEMENT_TYPE_P (Molecule, "molecule?");
 346 IMPLEMENT_DEFAULT_EQUAL_P (Molecule);
 347