src/tacvt.c

   1 /* tacvt.c */
   2
   3 /* written 2011 by Werner Lemberg <wl@gnu.org> */
   4
   5 #include "ta.h"
   6
   7
   8 static FT_Error
   9 TA_sfnt_compute_global_hints(SFNT* sfnt,
  10                              FONT* font)
  11 {
  12   FT_Error error;
  13   FT_Face face = sfnt->face;
  14   FT_UInt enc;
  15   FT_UInt idx;
  16
  17   static const FT_Encoding latin_encs[] =
  18   {
  19     FT_ENCODING_UNICODE,
  20     FT_ENCODING_APPLE_ROMAN,
  21     FT_ENCODING_ADOBE_STANDARD,
  22     FT_ENCODING_ADOBE_LATIN_1,
  23
  24     FT_ENCODING_NONE /* end of list */
  25   };
  26
  27
  28   error = ta_loader_init(font->loader);
  29   if (error)
  30     return error;
  31
  32   /* try to select a latin charmap */
  33   for (enc = 0; latin_encs[enc] != FT_ENCODING_NONE; enc++)
  34   {
  35     error = FT_Select_Charmap(face, latin_encs[enc]);
  36     if (!error)
  37       break;
  38   }
  39
  40   /* load latin glyph `a' to trigger all initializations */
  41   idx = FT_Get_Char_Index(face, 'a');
  42   error = ta_loader_load_glyph(font->loader, face, idx, 0);
  43
  44   return error;
  45 }
  46
  47
  48 static FT_Error
  49 TA_table_build_cvt(FT_Byte** cvt,
  50                    FT_ULong* cvt_len,
  51                    SFNT* sfnt,
  52                    FONT* font)
  53 {
  54   TA_LatinAxis haxis;
  55   TA_LatinAxis vaxis;
  56
  57   FT_UInt i;
  58   FT_UInt buf_len;
  59   FT_UInt len;
  60   FT_Byte* buf;
  61   FT_Byte* buf_p;
  62
  63   FT_Error error;
  64
  65
  66   error = TA_sfnt_compute_global_hints(sfnt, font);
  67   if (error)
  68     return error;
  69
  70   haxis = &((TA_LatinMetrics)font->loader->hints.metrics)->axis[0];
  71   vaxis = &((TA_LatinMetrics)font->loader->hints.metrics)->axis[1];
  72
  73   buf_len = 2 * (2
  74                  + haxis->width_count
  75                  + vaxis->width_count
  76                  + 2 * vaxis->blue_count);
  77
  78   /* buffer length must be a multiple of four */
  79   len = (buf_len + 3) & ~3;
  80   buf = (FT_Byte*)malloc(len);
  81   if (!buf)
  82     return FT_Err_Out_Of_Memory;
  83
  84   /* pad end of buffer with zeros */
  85   buf[len - 1] = 0x00;
  86   buf[len - 2] = 0x00;
  87   buf[len - 3] = 0x00;
  88
  89   buf_p = buf;
  90
  91   if (haxis->width_count > 0)
  92   {
  93     *(buf_p++) = HIGH(haxis->widths[0].org);
  94     *(buf_p++) = LOW(haxis->widths[0].org);
  95   }
  96   else
  97   {
  98     *(buf_p++) = 0;
  99     *(buf_p++) = 50;
 100   }
 101   if (vaxis->width_count > 0)
 102   {
 103     *(buf_p++) = HIGH(vaxis->widths[0].org);
 104     *(buf_p++) = LOW(vaxis->widths[0].org);
 105   }
 106   else
 107   {
 108     *(buf_p++) = 0;
 109     *(buf_p++) = 50;
 110   }
 111
 112   for (i = 0; i < haxis->width_count; i++)
 113   {
 114     if (haxis->widths[i].org > 0xFFFF)
 115       goto Err;
 116     *(buf_p++) = HIGH(haxis->widths[i].org);
 117     *(buf_p++) = LOW(haxis->widths[i].org);
 118   }
 119
 120   for (i = 0; i < vaxis->width_count; i++)
 121   {
 122     if (vaxis->widths[i].org > 0xFFFF)
 123       goto Err;
 124     *(buf_p++) = HIGH(vaxis->widths[i].org);
 125     *(buf_p++) = LOW(vaxis->widths[i].org);
 126   }
 127
 128   for (i = 0; i < vaxis->blue_count; i++)
 129   {
 130     if (vaxis->blues[i].ref.org > 0xFFFF)
 131       goto Err;
 132     *(buf_p++) = HIGH(vaxis->blues[i].ref.org);
 133     *(buf_p++) = LOW(vaxis->blues[i].ref.org);
 134   }
 135
 136   for (i = 0; i < vaxis->blue_count; i++)
 137   {
 138     if (vaxis->blues[i].shoot.org > 0xFFFF)
 139       goto Err;
 140     *(buf_p++) = HIGH(vaxis->blues[i].shoot.org);
 141     *(buf_p++) = LOW(vaxis->blues[i].shoot.org);
 142   }
 143
 144 #if 0
 145   TA_LOG(("--------------------------------------------------\n"));
 146   TA_LOG(("glyph %d:\n", idx));
 147   ta_glyph_hints_dump_edges(_ta_debug_hints);
 148   ta_glyph_hints_dump_segments(_ta_debug_hints);
 149   ta_glyph_hints_dump_points(_ta_debug_hints);
 150 #endif
 151
 152   *cvt = buf;
 153   *cvt_len = buf_len;
 154
 155   return FT_Err_Ok;
 156
 157 Err:
 158   free(buf);
 159   return TA_Err_Hinter_Overflow;
 160 }
 161
 162
 163 FT_Error
 164 TA_sfnt_build_cvt_table(SFNT* sfnt,
 165                         FONT* font)
 166 {
 167   FT_Error error;
 168
 169   FT_Byte* cvt_buf;
 170   FT_ULong cvt_len;
 171
 172
 173   error = TA_sfnt_add_table_info(sfnt);
 174   if (error)
 175     return error;
 176
 177   error = TA_table_build_cvt(&cvt_buf, &cvt_len, sfnt, font);
 178   if (error)
 179     return error;
 180
 181   /* in case of success, `cvt_buf' gets linked */
 182   /* and is eventually freed in `TA_font_unload' */
 183   error = TA_font_add_table(font,
 184                             &sfnt->table_infos[sfnt->num_table_infos - 1],
 185                             TTAG_cvt, cvt_len, cvt_buf);
 186   if (error)
 187   {
 188     free(cvt_buf);
 189     return error;
 190   }
 191
 192   return FT_Err_Ok;
 193 }
 194
 195 /* end of tacvt.c */