Get supported characters

[RoelN]

What'd be the intented way to get a list of supported chars from the cmap table, other than looping over every unicode value and passing it to supports()?

I figured I could use startCode and endCode to get unicode ranges, but it there appears to be some noise in those arrays, e.g.:

[32, 38, 44, 48, 58, 63, 65, 91, 95, 97, 105, 160, 171, 187, 191, 8211, 8216, 8220, 8230, 8249, 65535, 0, 0, 0, 45, 9, 65534, 65474, 0, 65533, 65468, 0, 0, 65441, 65426, 65407, 57415, 57392, 57386, 57375, 57365, 1]

(Last supported character is 8249, after which it jumps to 65535 and some zeroes etc.)

[Pomax]

depends entirely on the subtables covered by cmap, really. We could add a "getSupportedCharCodes()", but remember that only subtables with a Unicode platform/encoding/language tuple uses character codes based on Unicode code point values.

For subformat 4, it'd indeed involve running through the segments - if you're seeing consecutive segments with unordered endCode values, we'll have to look at that more closely: that'd be a parsing bug.

[Pomax]

Looking at the subformat 4 segments and subformat 12 groups for the Adobe Source Pro fonts used for testing, I don't see out-of-sequence data:

// subtable format 4
otf.opentype.tables.cmap.get(0).segments.map(v => v.endCode).join(', ')
"47, 64, 96, 126, 191, 209, 223, 241, 384, 394, 399, 403, 417, 432, 450, 476, 483, 487,
491, 501, 511, 539, 567, 579, 593, 600, 604, 616, 618, 622, 630, 635, 638, 644, 658,
661, 665, 671, 674, 676, 679, 688, 691, 697, 700, 703, 705, 716, 721, 734, 740, 780,
787, 800, 810, 812, 817, 820, 829, 834, 837, 863, 865, 885, 890, 894, 906, 908, 912,
929, 939, 944, 962, 974, 977, 981, 983, 985, 987, 989, 993, 1039, 1071, 1119, 1123,
1141, 1171, 1179, 1187, 1195, 1203, 1207, 1211, 1218, 1233, 1241, 1251, 1257,
1263, 1267, 7491, 7497, 7501, 7504, 7506, 7512, 7515, 7580, 7584, 7611, 7687,
7697, 7703, 7713, 7723, 7739, 7753, 7763, 7779, 7791, 7813, 7831, 7838, 7929,
8129, 8143, 8159, 8175, 8190, 8199, 8208, 8222, 8226, 8230, 8240, 8243, 8245,
8250, 8255, 8260, 8265, 8305, 8313, 8319, 8329, 8334, 8340, 8353, 8356, 8359,
8361, 8364, 8366, 8370, 8373, 8378, 8381, 8453, 8467, 8471, 8480, 8482, 8486,
8494, 8530, 8538, 8542, 8585, 8597, 8601, 8616, 8659, 8704, 8707, 8710, 8719,
8722, 8725, 8730, 8735, 8745, 8747, 8759, 8776, 8801, 8805, 8962, 8976, 8993,
9633, 9644, 9658, 9668, 9670, 9676, 9679, 9689, 9702, 9745, 9749, 9788, 9792,
9794, 9824, 9827, 9830, 9835, 10003, 10066, 10084, 10215, 11800, 11813, 57506,
57523, 64258, 65039, 65279, 65535"

// subtable format 12
otf.opentype.tables.cmap.get(1).groups.map(v => v.endCharCode).join(', ')
"32, 33, 34, 35, 36, 37, 38, 39, 41, 42, 43, 44, 45, 46, 47, 57, 59, 60, 61,
62, 63, 64, 90, 91, 92, 93, 94, 95,96,
122, 123, 124, 125, 126, 160, 161, 162, 163, 164, 165, 166, 167,
168, 169, 170, 171, 172, 173, 174, 175, 176, 177, 179, 180, 181, 182, 183, 184, 185,
186, 187, 190, 191, 196, 197, 198, 199, 202, 203, 206, 207, 208, 209, 214, 215, 216,
219, 220, 221, 222, 223, 228, 229, 230, 231, 234, 235, 238, 239, 240, 241, 246, 247,
248, 251, 252, 253, 254, 255, 256, 257, 258, 259, 260, 261, 262, 263, 264, 265, 266,
267, 268, 269, 270, 271, 272, 273, 274, 275, 276, 277, 278, 279, 280, 281, 282, 283,
284, 285, 286, 287, 288, 289, 290, 291, 292, 293, 294, 295, 296, 297, 298, 299, 300,
301, 302, 303, 304, 305, 306, 307, 308, 309, 310, 311, 312, 313, 314, 315, 316, 317,
318, 319, 320, 321, 322, 323, 324, 325, 326, 327, 328, 329, 330, 331, 332, 333, 334,
335, 336, 337, 338, 339, 340, 341, 342, 343, 344, 345, 346, 347, 348, 349, 350, 351,
352, 353, 354, 355, 356, 357, 358, 359, 360, 361, 362, 363, 364, 365, 366, 367, 368,
369, 370, 371, 372, 373, 374, 375, 376, 377, 378, 379, 380, 381, 382, 383, 384, 394,
399, 402, 403, 416, 417, 431, 432, 450, 461, 462, 463, 464, 465, 466, 467, 468, 469,
470, 471, 472, 473, 474, 475, 476, 482, 483, 486, 487, 490, 491, 500, 501, 504, 505,
506, 507, 508, 509, 510, 511, 536, 537, 538, 539, 567, 579, 592, 593, 600, 604, 615,
616, 618, 622, 630, 635, 638, 644, 658, 661, 664, 665, 668, 670, 671, 674, 676, 679,
688, 690, 691, 695, 696, 697, 700, 703, 705, 716, 721, 728, 729, 730, 731, 732, 733,
734, 736, 737, 738, 739, 740, 768, 769, 770, 771, 772, 773, 774, 775, 776, 777, 778,
779, 780, 783, 784, 785, 786, 787, 800, 806, 807, 808, 810, 812, 817, 820, 829, 834,
837, 863, 865, 885, 890, 894, 900, 901, 902, 903, 906, 908, 910, 911, 912, 929, 937,
938, 939, 943, 944, 961, 962, 969, 970, 971, 973, 974, 977, 981, 983, 985, 987, 989,
993, 1039, 1071, 1119, 1122, 1123, 1138, 1139, 1140, 1141, 1168, 1169, 1170, 1171,
1174, 1175, 1176, 1177, 1178, 1179, 1184, 1185, 1186, 1187, 1194, 1195, 1198, 1199,
1200, 1201, 1202, 1203, 1206, 1207, 1210, 1211, 1217, 1218, 1231, 1232, 1233, 1236,
1237, 1238, 1239, 1240, 1241, 1250, 1251, 1254, 1255, 1256, 1257, 1262, 1263, 1266,
1267, 7491, 7495, 7497, 7501, 7503, 7504, 7506, 7510, 7512, 7515, 7580, 7584, 7611,
7686, 7687, 7692, 7693, 7694, 7695, 7696, 7697, 7702, 7703, 7712, 7713, 7716, 7717,
7718, 7719, 7720, 7721, 7722, 7723, 7730, 7731, 7732, 7733, 7734, 7735, 7736, 7737,
7738, 7739, 7742, 7743, 7744, 7745, 7746, 7747, 7748, 7749, 7750, 7751, 7752, 7753,
7762, 7763, 7768, 7769, 7770, 7771, 7772, 7773, 7774, 7775, 7776, 7777, 7778, 7779,
7788, 7789, 7790, 7791, 7806, 7807, 7808, 7809, 7810, 7811, 7812, 7813, 7822, 7823,
7824, 7825, 7826, 7827, 7828, 7829, 7830, 7831, 7838, 7840, 7841, 7842, 7843, 7844,
7845, 7846, 7847, 7848, 7849, 7850, 7851, 7852, 7853, 7854, 7855, 7856, 7857, 7858,
7859, 7860, 7861, 7862, 7863, 7864, 7865, 7866, 7867, 7868, 7869, 7870, 7871, 7872,
7873, 7874, 7875, 7876, 7877, 7878, 7879, 7880, 7881, 7882, 7883, 7884, 7885, 7886,
7887, 7888, 7889, 7890, 7891, 7892, 7893, 7894, 7895, 7896, 7897, 7898, 7899, 7900,
7901, 7902, 7903, 7904, 7905, 7906, 7907, 7908, 7909, 7910, 7911, 7912, 7913, 7914,
7915, 7916, 7917, 7918, 7919, 7920, 7921, 7922, 7923, 7924, 7925, 7926, 7927, 7928,
7929, 8125, 8126, 8127, 8128, 8129, 8141, 8142, 8143, 8157, 8158, 8159, 8174, 8175,
8189, 8190, 8199, 8208, 8210, 8212, 8213, 8214, 8215, 8217, 8218, 8219, 8221, 8222,
8225, 8226, 8230, 8239, 8240, 8243, 8245, 8250, 8252, 8253, 8255, 8260, 8263, 8264,
8265, 8304, 8305, 8313, 8318, 8319, 8329, 8334, 8340, 8353, 8355, 8356, 8359, 8361,
8363, 8364, 8366, 8370, 8373, 8376, 8378, 8381, 8453, 8467, 8470, 8471, 8480, 8482,
8486, 8494, 8528, 8530, 8538, 8542, 8585, 8595, 8597, 8601, 8616, 8659, 8704, 8706,
8707, 8710, 8719, 8721, 8722, 8725, 8729, 8730, 8734, 8735, 8745, 8747, 8759, 8776,
8800, 8801, 8805, 8962, 8976, 8991, 8993, 9631, 9633, 9643, 9644, 9651, 9653, 9655,
9657, 9658, 9661, 9663, 9665, 9667, 9668, 9670, 9673, 9674, 9675, 9676, 9679, 9688,
9689, 9702, 9745, 9749, 9787, 9788, 9792, 9794, 9824, 9827, 9829, 9830, 9835, 10003,
10066, 10084, 10215, 11800, 11813, 57506, 57523, 64258, 65039, 65279, 127926,
128169, 128274, 129302"

[Pomax]

I've rejiggered the cmap a little so that you can get a (segmented) list of supported charcodes for all tables by using:

myFont.opentype.tables.cmap.encodingRecords.map(r => r.table.getSupportedCharCodes());

(But remember that non-unicode subtables are still very much "who knows, might even include charcodes for things that aren't in unicode" =D)

As you can see, records now have a direct .table property that gets you the cmap subtable, and I've also renamed the cmap-level get(tableID) to getSubTable(tableID) just so that it's clearer what it's fetching for you.

[RoelN]

I'm gettings this for Fraunces, a random font I was testing with:

console.log(e.detail.font.opentype.tables.cmap.get(1).startCode);
(42) [32, 38, 44, 48, 58, 63, 65, 91, 95, 97, 105, 160, 171, 187, 191, 8211, 8216, 8220, 8230, 8249, 65535, 0, 0, 0, 45, 9, 65534, 65474, 0, 65533, 65468, 0, 0, 65441, 65426, 65407, 57415, 57392, 57386, 57375, 57365, 1]

EDIT: This was still on the previous version. After a pull, the rejiggered version works like a charm! Thanks!

[Pomax]

Oh, weird. Good to know the rejigger jiggered things into the correct sequence =D