lily/paper-def.cc

   1 /*
   2   This file is part of LilyPond, the GNU music typesetter.
   3
   4   Copyright (C) 2004--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 "dimensions.hh"
  21 #include "output-def.hh"
  22 #include "modified-font-metric.hh"
  23 #include "pango-font.hh"
  24 #include "all-font-metrics.hh"
  25
  26 Real
  27 output_scale (Output_def *od)
  28 {
  29   return scm_to_double (od->lookup_variable (ly_symbol2scm ("output-scale")));
  30 }
  31
  32 SCM
  33 get_font_table (Output_def *def)
  34 {
  35   SCM font_table = def->lookup_variable (ly_symbol2scm ("scaled-fonts"));
  36   if (scm_hash_table_p (font_table) != SCM_BOOL_T)
  37     {
  38       font_table = scm_c_make_hash_table (11);
  39       def->set_variable (ly_symbol2scm ("scaled-fonts"), font_table);
  40     }
  41   return font_table;
  42 }
  43
  44 SCM
  45 get_pango_font_table (Output_def *def)
  46 {
  47   SCM font_table = def->lookup_variable (ly_symbol2scm ("pango-fonts"));
  48   if (scm_hash_table_p (font_table) != SCM_BOOL_T)
  49     {
  50       font_table = scm_c_make_hash_table (11);
  51       def->set_variable (ly_symbol2scm ("pango-fonts"), font_table);
  52     }
  53   return font_table;
  54 }
  55
  56 /* TODO: should add nesting for Output_def here too. */
  57 Font_metric *
  58 find_scaled_font (Output_def *mod, Font_metric *f, Real m)
  59 {
  60   if (mod->parent_)
  61     return find_scaled_font (mod->parent_, f, m);
  62
  63   Real lookup_mag = m / output_scale (mod);
  64
  65   SCM font_table = get_font_table (mod);
  66   SCM sizes = scm_hashq_ref (font_table, f->self_scm (), SCM_EOL);
  67   SCM handle = scm_assoc (scm_from_double (lookup_mag), sizes);
  68   if (scm_is_pair (handle))
  69     return unsmob_metrics (scm_cdr (handle));
  70
  71   SCM val = Modified_font_metric::make_scaled_font_metric (f, lookup_mag);
  72
  73   sizes = scm_acons (scm_from_double (lookup_mag), val, sizes);
  74   unsmob_metrics (val)->unprotect ();
  75   scm_hashq_set_x (font_table, f->self_scm (), sizes);
  76   return unsmob_metrics (val);
  77 }
  78
  79 Font_metric *
  80 find_pango_font (Output_def *layout, SCM descr, Real factor)
  81 {
  82   if (layout->parent_)
  83     return find_pango_font (layout->parent_, descr, factor);
  84
  85   SCM table = get_pango_font_table (layout);
  86   SCM sizes = scm_hash_ref (table, descr, SCM_EOL);
  87   SCM size_key = scm_from_double (factor);
  88   SCM handle = scm_assoc (size_key, sizes);
  89   if (scm_is_pair (handle))
  90     return unsmob_metrics (scm_cdr (handle));
  91
  92   PangoFontDescription *description
  93     = pango_font_description_from_string (scm_i_string_chars (descr));
  94
  95   pango_font_description_set_size (description,
  96                                    gint (factor *
  97                                          pango_font_description_get_size (description)));
  98
  99
 100   Font_metric *fm = all_fonts_global->find_pango_font (description,
 101                                                        output_scale (layout));
 102
 103   pango_font_description_free (description);
 104
 105   sizes = scm_acons (size_key, fm->self_scm (), sizes);
 106   scm_hash_set_x (table, descr, sizes);
 107
 108   return fm;
 109 }
 110
 111 /* TODO: this is a nasty interface. During formatting,
 112    the Output_def should be scaled to the output_scale_
 113    specified in the toplevel Output_def.  */
 114 Output_def *
 115 scale_output_def (Output_def *o, Real amount)
 116 {
 117   SCM proc = ly_lily_module_constant ("scale-layout");
 118   SCM new_pap = scm_call_2 (proc, o->self_scm (), scm_from_double (amount));
 119
 120   o = unsmob_output_def (new_pap);
 121   o->protect ();
 122   return o;
 123 }
 124