lily/molecule-scheme.cc

   1 /*
   2   molecule-scheme.cc -- implement Molecule
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c)  1997--2003 Han-Wen Nienhuys <hanwen@cs.uu.nl>
   7 */
   8
   9 #include "molecule.hh"
  10 #include "font-metric.hh"
  11
  12 LY_DEFINE(ly_molecule_set_extent_x,"ly:molecule-set-extent!", 3 , 0, 0,
  13           (SCM mol, SCM axis, SCM np),
  14           "Set the extent (@var{extent} must be a pair of numbers) of @var{mol} in \n"
  15 "@var{axis} direction (0 or 1 for x- and y-axis respectively).\n"
  16 "\n"
  17 "Note that an extent @code{(A . B)} is an interval and hence @code{A} is\n"
  18 "smaller than @code{B}, and is often negative.\n"
  19 )
  20 {
  21   Molecule* m = unsmob_molecule (mol);
  22   SCM_ASSERT_TYPE (m, mol, SCM_ARG1, __FUNCTION__, "molecule");
  23   SCM_ASSERT_TYPE (ly_axis_p (axis), axis, SCM_ARG2, __FUNCTION__, "axis");
  24   SCM_ASSERT_TYPE (ly_number_pair_p (np), np, SCM_ARG3, __FUNCTION__, "number pair");
  25
  26   Interval iv = ly_scm2interval (np);
  27   m->dim_[Axis (gh_scm2int (axis))] = iv;
  28
  29   return SCM_UNDEFINED;
  30 }
  31
  32
  33 LY_DEFINE(ly_translate_molecule_axis,"ly:molecule-translate-axis", 3, 0, 0,
  34           (SCM mol, SCM amount, SCM axis),
  35           "Return a @var{mol}, but translated by @var{amount} in @var{axis} direction")
  36 {
  37   Molecule* m = unsmob_molecule (mol);
  38   SCM_ASSERT_TYPE (m, mol, SCM_ARG1, __FUNCTION__, "molecule");
  39   SCM_ASSERT_TYPE (gh_number_p (amount), amount, SCM_ARG2, __FUNCTION__, "number pair");
  40   SCM_ASSERT_TYPE (ly_axis_p (axis), axis, SCM_ARG3, __FUNCTION__, "axis");
  41
  42
  43   Molecule q (*m);
  44   q.translate_axis (gh_scm2double (amount), Axis (gh_scm2int (axis)));
  45
  46   return q.smobbed_copy();
  47 }
  48
  49 LY_DEFINE(ly_translate_molecule,"ly:molecule-translate", 2, 0, 0,
  50           (SCM mol, SCM offset),
  51           "Return a @var{mol}, but translated by @var{offset} (a pair of numbers).")
  52 {
  53   Molecule* m = unsmob_molecule (mol);
  54   SCM_ASSERT_TYPE (m, mol, SCM_ARG1, __FUNCTION__, "molecule");
  55   SCM_ASSERT_TYPE (ly_number_pair_p (offset), offset, SCM_ARG2, __FUNCTION__, "number pair");
  56   Offset o = ly_scm2offset (offset);
  57
  58   Molecule q (*m);
  59   q.translate (o);
  60   return q.smobbed_copy();
  61 }
  62
  63 LY_DEFINE(ly_molecule_get_extent,
  64           "ly:molecule-get-extent", 2 , 0, 0,  (SCM mol, SCM axis),
  65           "Return a pair of numbers signifying the extent of @var{mol} in "
  66 "@var{axis} direction (0 or 1 for x and y axis respectively)."
  67 )
  68 {
  69   Molecule *m = unsmob_molecule (mol);
  70   SCM_ASSERT_TYPE (m, mol, SCM_ARG1, __FUNCTION__, "molecule");
  71   SCM_ASSERT_TYPE (ly_axis_p (axis), axis, SCM_ARG2, __FUNCTION__, "axis");
  72
  73   return ly_interval2scm (m->extent (Axis (gh_scm2int (axis))));
  74 }
  75
  76
  77 LY_DEFINE(ly_molecule_combined_at_edge,
  78           "ly:molecule-combine-at-edge",
  79           4, 2, 0,  (SCM first, SCM axis, SCM direction,
  80                      SCM second,
  81                      SCM padding,
  82                      SCM minimum),
  83           "Construct a molecule by putting @var{second} next to "
  84 "@var{first}. @var{axis} can be 0 (x-axis) or 1 (y-axis), @var{direction} can be "
  85 "-1 (left or down) or 1 (right or up). "
  86 "The molecules are juxtaposed with  @var{padding} as extra space. If "
  87 "this puts the reference points closer than @var{minimum}, they are moved "
  88 "by the latter amount.")
  89
  90 {
  91   Molecule * m1 = unsmob_molecule (first);
  92   Molecule * m2 = unsmob_molecule (second);
  93   Molecule result;
  94
  95
  96   SCM_ASSERT_TYPE(ly_axis_p (axis), axis, SCM_ARG3, __FUNCTION__, "axis");
  97   SCM_ASSERT_TYPE(ly_dir_p (direction), direction, SCM_ARG4, __FUNCTION__, "dir");
  98
  99   Real p = 0.0;
 100   if (padding != SCM_UNDEFINED)
 101     {
 102       SCM_ASSERT_TYPE(gh_number_p (padding), padding, SCM_ARG5, __FUNCTION__, "number");
 103       p = gh_scm2double (padding);
 104     }
 105   Real m =0.0;
 106   if (minimum != SCM_UNDEFINED)
 107     {
 108       SCM_ASSERT_TYPE(gh_number_p (minimum), minimum, SCM_ARG6, __FUNCTION__, "number");
 109       m = gh_scm2double (minimum);
 110     }
 111
 112   if (m1)
 113     result = *m1;
 114   if (m2)
 115     result.add_at_edge (Axis (gh_scm2int (axis)), Direction (gh_scm2int (direction)),
 116                         *m2, p, m);
 117
 118   return result.smobbed_copy ();
 119 }
 120
 121 /*
 122   FIXME: support variable number of arguments "
 123  */
 124 LY_DEFINE(ly_molecule_add ,
 125           "ly:molecule-add", 2, 0, 0, (SCM first, SCM second),
 126           "Combine two molecules."
 127           )
 128 {
 129   Molecule * m1 = unsmob_molecule (first);
 130   Molecule * m2 = unsmob_molecule (second);
 131   Molecule result;
 132
 133
 134   if (m1)
 135     result = *m1;
 136   if (m2)
 137     result.add_molecule (*m2);
 138
 139   return result.smobbed_copy ();
 140 }
 141
 142 LY_DEFINE(ly_make_molecule,
 143           "ly:make-molecule", 3, 0, 0,  (SCM expr, SCM xext, SCM yext),
 144           " \n"
 145 "The objective of any typesetting system is to put ink on paper in the \n"
 146 "right places. For LilyPond, this final stage is left to the @TeX{} and \n"
 147 "the printer subsystem. For lily, the last stage in processing a score is \n"
 148 "outputting a description of what to put where.  This description roughly \n"
 149 "looks like \n"
 150 "@example \n"
 151 "        PUT glyph AT (x,y) \n"
 152 "        PUT glyph AT (x,y) \n"
 153 "        PUT glyph AT (x,y)  \n"
 154 "@end example \n"
 155 "you merely have to look at the tex output of lily to see this. \n"
 156 "Internally these instructions are encoded in Molecules.@footnote{At some \n"
 157 "point LilyPond also contained Atom-objects, but they have been replaced \n"
 158 "by Scheme expressions, making the name outdated.}  A molecule is \n"
 159 "what-to-print-where information that also contains dimension information \n"
 160 "(how large is this glyph?). \n"
 161 " \n"
 162 "Conceptually, Molecules can be constructed from Scheme code, by \n"
 163 "translating a Molecule and by combining two molecules. In BNF \n"
 164 "notation: \n"
 165 " \n"
 166 "@example \n"
 167 "Molecule  :: COMBINE Molecule Molecule \n"
 168 "           | TRANSLATE Offset Molecule \n"
 169 "           | GLYPH-DESCRIPTION \n"
 170 "           ; \n"
 171 "@end example \n"
 172 " \n"
 173 "If you are interested in seeing how this information is stored, you \n"
 174 "can run with the @code{-f scm} option. The scheme expressions are then \n"
 175 "dumped in the output file.")
 176 {
 177   SCM_ASSERT_TYPE (ly_number_pair_p (xext), xext, SCM_ARG2, __FUNCTION__, "number pair");
 178   SCM_ASSERT_TYPE (ly_number_pair_p (yext), yext, SCM_ARG3, __FUNCTION__, "number pair");
 179
 180   Box b (ly_scm2interval (xext), ly_scm2interval(yext));
 181   Molecule m (b, expr);
 182   return m.smobbed_copy ();
 183 }
 184
 185
 186 SCM
 187 fontify_atom (Font_metric const * met, SCM f)
 188 {
 189   if (f == SCM_EOL)
 190     return f;
 191   else
 192     return  scm_list_n (ly_symbol2scm ("fontify"),
 193                         ly_quote_scm (met->description_), f, SCM_UNDEFINED);
 194 }
 195
 196 LY_DEFINE(ly_fontify_atom,"ly:fontify-atom", 2, 0, 0,
 197           (SCM met, SCM f),
 198           "Add a font selection command for the font metric @var{met} to @var{f}.")
 199 {
 200   SCM_ASSERT_TYPE(unsmob_metrics (met), met, SCM_ARG1, __FUNCTION__, "font metric");
 201
 202   return fontify_atom (unsmob_metrics (met), f);
 203 }
 204 LY_DEFINE(ly_align_to_x,"ly:molecule-align-to!", 3, 0, 0,  (SCM mol, SCM axis, SCM dir),
 205           "Align @var{mol} using its own extents.")
 206 {
 207   SCM_ASSERT_TYPE(unsmob_molecule (mol), mol, SCM_ARG1, __FUNCTION__, "molecule");
 208   SCM_ASSERT_TYPE(ly_axis_p (axis), axis, SCM_ARG2, __FUNCTION__, "axis");
 209   SCM_ASSERT_TYPE(ly_dir_p (dir), dir, SCM_ARG3, __FUNCTION__, "dir");
 210
 211   unsmob_molecule (mol)->align_to ((Axis)gh_scm2int (axis), Direction (gh_scm2int (dir)));
 212
 213   return SCM_UNDEFINED;
 214 }