lily/stencil-interpret.cc

   1 /*
   2   This file is part of LilyPond, the GNU music typesetter.
   3
   4   Copyright (C) 2005--2011 Han-Wen Nienhuys <hanwen@xs4all.nl>
   5
   6   LilyPond is free software: you can redistribute it and/or modify
   7   it under the terms of the GNU General Public License as published by
   8   the Free Software Foundation, either version 3 of the License, or
   9   (at your option) any later version.
  10
  11   LilyPond is distributed in the hope that it will be useful,
  12   but WITHOUT ANY WARRANTY; without even the implied warranty of
  13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14   GNU General Public License for more details.
  15
  16   You should have received a copy of the GNU General Public License
  17   along with LilyPond.  If not, see <http://www.gnu.org/licenses/>.
  18 */
  19
  20 #include "stencil.hh"
  21
  22 void
  23 interpret_stencil_expression (SCM expr,
  24                               void (*func) (void *, SCM),
  25                               void *func_arg,
  26                               Offset o)
  27 {
  28   while (1)
  29     {
  30       if (!scm_is_pair (expr))
  31         return;
  32
  33       SCM head = scm_car (expr);
  34
  35       if (head == ly_symbol2scm ("delay-stencil-evaluation"))
  36         {
  37           interpret_stencil_expression (scm_force (scm_cadr (expr)), func, func_arg, o);
  38           return;
  39         }
  40       if (head == ly_symbol2scm ("footnote"))
  41         return;
  42       if (head == ly_symbol2scm ("translate-stencil"))
  43         {
  44           o += ly_scm2offset (scm_cadr (expr));
  45           expr = scm_caddr (expr);
  46         }
  47       else if (head == ly_symbol2scm ("combine-stencil"))
  48         {
  49
  50           for (SCM x = scm_cdr (expr); scm_is_pair (x); x = scm_cdr (x))
  51             interpret_stencil_expression (scm_car (x), func, func_arg, o);
  52           return;
  53         }
  54       else if (head == ly_symbol2scm ("grob-cause"))
  55         {
  56           SCM grob = scm_cadr (expr);
  57
  58           (*func) (func_arg, scm_list_3 (head,
  59                                          ly_quote_scm (ly_offset2scm (o)), grob));
  60           interpret_stencil_expression (scm_caddr (expr), func, func_arg, o);
  61           (*func) (func_arg, scm_list_1 (ly_symbol2scm ("no-origin")));
  62           return;
  63         }
  64       else if (head == ly_symbol2scm ("color"))
  65         {
  66           SCM color = scm_cadr (expr);
  67           SCM r = scm_car (color);
  68           SCM g = scm_cadr (color);
  69           SCM b = scm_caddr (color);
  70
  71           (*func) (func_arg, scm_list_4 (ly_symbol2scm ("setcolor"), r, g, b));
  72           interpret_stencil_expression (scm_caddr (expr), func, func_arg, o);
  73           (*func) (func_arg, scm_list_1 (ly_symbol2scm ("resetcolor")));
  74
  75           return;
  76         }
  77       else if (head == ly_symbol2scm ("rotate-stencil"))
  78         {
  79           SCM args = scm_cadr (expr);
  80           SCM angle = scm_car (args);
  81           Offset tmp = o + robust_scm2offset (scm_cadr (args), Offset (0.0, 0.0));
  82
  83           SCM offset = ly_offset2scm (tmp);
  84           SCM x = scm_car (offset);
  85           SCM y = scm_cdr (offset);
  86
  87           (*func) (func_arg, scm_list_4 (ly_symbol2scm ("setrotation"), angle, x, y));
  88           interpret_stencil_expression (scm_caddr (expr), func, func_arg, o);
  89           (*func) (func_arg, scm_list_4 (ly_symbol2scm ("resetrotation"), angle, x, y));
  90
  91           return;
  92         }
  93       else if (head == ly_symbol2scm ("scale-stencil"))
  94         {
  95           SCM args = scm_cadr (expr);
  96           SCM x_scale = scm_car (args);
  97           SCM y_scale = scm_cadr (args);
  98           Offset unscaled = o.scale (Offset (1 / scm_to_double (x_scale),
  99                                              1 / scm_to_double (y_scale)));
 100
 101           (*func) (func_arg, scm_list_3 (ly_symbol2scm ("setscale"), x_scale,
 102                                          y_scale));
 103           interpret_stencil_expression (scm_caddr (expr), func, func_arg,
 104                                         unscaled);
 105           (*func) (func_arg, scm_list_1 (ly_symbol2scm ("resetscale")));
 106
 107           return;
 108         }
 109       else
 110         {
 111           (*func) (func_arg,
 112                    scm_list_4 (ly_symbol2scm ("placebox"),
 113                                scm_from_double (o[X_AXIS]),
 114                                scm_from_double (o[Y_AXIS]),
 115                                expr));
 116           return;
 117         }
 118     }
 119 }
 120
 121 struct Font_list
 122 {
 123   SCM fonts_;
 124 };
 125
 126 static void
 127 find_font_function (void *fs, SCM x)
 128 {
 129   Font_list *me = (Font_list *) fs;
 130
 131   if (scm_car (x) == ly_symbol2scm ("placebox"))
 132     {
 133       SCM args = scm_cdr (x);
 134       SCM what = scm_caddr (args);
 135
 136       if (scm_is_pair (what))
 137         {
 138           SCM head = scm_car (what);
 139           if (ly_symbol2scm ("text") == head)
 140             me->fonts_ = scm_cons (scm_cadr (what), me->fonts_);
 141           else if (head == ly_symbol2scm ("char"))
 142             me->fonts_ = scm_cons (scm_cadr (what), me->fonts_);
 143         }
 144     }
 145 }
 146
 147 SCM
 148 find_expression_fonts (SCM expr)
 149 {
 150   Font_list fl;
 151
 152   fl.fonts_ = SCM_EOL;
 153
 154   interpret_stencil_expression (expr, &find_font_function,
 155                                 (void *) & fl, Offset (0, 0));
 156
 157   return fl.fonts_;
 158 }