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 ("translate-stencil"))
  41         {
  42           o += ly_scm2offset (scm_cadr (expr));
  43           expr = scm_caddr (expr);
  44         }
  45       else if (head == ly_symbol2scm ("combine-stencil"))
  46         {
  47
  48           for (SCM x = scm_cdr (expr); scm_is_pair (x); x = scm_cdr (x))
  49             interpret_stencil_expression (scm_car (x), func, func_arg, o);
  50           return;
  51         }
  52       else if (head == ly_symbol2scm ("grob-cause"))
  53         {
  54           SCM grob = scm_cadr (expr);
  55
  56           (*func) (func_arg, scm_list_3 (head,
  57                                          ly_quote_scm (ly_offset2scm (o)), grob));
  58           interpret_stencil_expression (scm_caddr (expr), func, func_arg, o);
  59           (*func) (func_arg, scm_list_1 (ly_symbol2scm ("no-origin")));
  60           return;
  61         }
  62       else if (head == ly_symbol2scm ("color"))
  63         {
  64           SCM color = scm_cadr (expr);
  65           SCM r = scm_car (color);
  66           SCM g = scm_cadr (color);
  67           SCM b = scm_caddr (color);
  68
  69           (*func) (func_arg, scm_list_4 (ly_symbol2scm ("setcolor"), r, g, b));
  70           interpret_stencil_expression (scm_caddr (expr), func, func_arg, o);
  71           (*func) (func_arg, scm_list_1 (ly_symbol2scm ("resetcolor")));
  72
  73           return;
  74         }
  75       else if (head == ly_symbol2scm ("rotate-stencil"))
  76         {
  77           SCM args = scm_cadr (expr);
  78           SCM angle = scm_car (args);
  79           Offset tmp = o + robust_scm2offset (scm_cadr (args), Offset (0.0, 0.0));
  80
  81           SCM offset = ly_offset2scm (tmp);
  82           SCM x = scm_car (offset);
  83           SCM y = scm_cdr (offset);
  84
  85           (*func) (func_arg, scm_list_4 (ly_symbol2scm ("setrotation"), angle, x, y));
  86           interpret_stencil_expression (scm_caddr (expr), func, func_arg, o);
  87           (*func) (func_arg, scm_list_4 (ly_symbol2scm ("resetrotation"), angle, x, y));
  88
  89           return;
  90         }
  91       else if (head == ly_symbol2scm ("scale-stencil"))
  92         {
  93           SCM args = scm_cadr (expr);
  94           SCM x_scale = scm_car (args);
  95           SCM y_scale = scm_cadr (args);
  96           Offset unscaled = o.scale (Offset (1 / scm_to_double (x_scale),
  97                                              1 / scm_to_double (y_scale)));
  98
  99           (*func) (func_arg, scm_list_3 (ly_symbol2scm ("setscale"), x_scale,
 100                                          y_scale));
 101           interpret_stencil_expression (scm_caddr (expr), func, func_arg,
 102                                         unscaled);
 103           (*func) (func_arg, scm_list_1 (ly_symbol2scm ("resetscale")));
 104
 105           return;
 106         }
 107       else
 108         {
 109           (*func) (func_arg,
 110                    scm_list_4 (ly_symbol2scm ("placebox"),
 111                                scm_from_double (o[X_AXIS]),
 112                                scm_from_double (o[Y_AXIS]),
 113                                expr));
 114           return;
 115         }
 116     }
 117 }
 118
 119 struct Font_list
 120 {
 121   SCM fonts_;
 122 };
 123
 124 static void
 125 find_font_function (void *fs, SCM x)
 126 {
 127   Font_list *me = (Font_list *) fs;
 128
 129   if (scm_car (x) == ly_symbol2scm ("placebox"))
 130     {
 131       SCM args = scm_cdr (x);
 132       SCM what = scm_caddr (args);
 133
 134       if (scm_is_pair (what))
 135         {
 136           SCM head = scm_car (what);
 137           if (ly_symbol2scm ("text") == head)
 138             me->fonts_ = scm_cons (scm_cadr (what), me->fonts_);
 139           else if (head == ly_symbol2scm ("char"))
 140             me->fonts_ = scm_cons (scm_cadr (what), me->fonts_);
 141         }
 142     }
 143 }
 144
 145 SCM
 146 find_expression_fonts (SCM expr)
 147 {
 148   Font_list fl;
 149
 150   fl.fonts_ = SCM_EOL;
 151
 152   interpret_stencil_expression (expr, &find_font_function,
 153                                 (void *) & fl, Offset (0, 0));
 154
 155   return fl.fonts_;
 156 }