1
   2
   3
   4
   5
   6
   7
   8
   9
  10
  11
  12
  13
  14
  15
  16
  17
  18
  19
  20
  21
  22
  23
  24
  25
  26
  27
  28
  29
  30
  31
  32
  33
  34
  35
  36
  37
  38
  39
  40
  41
  42
  43
  44
  45
  46
  47
  48
  49
  50
  51
  52
  53
  54
  55
  56
  57
  58
  59
  60
  61
  62
  63
  64
  65
  66
  67
  68
  69
  70
  71
  72
  73
  74
  75
  76
  77
  78
  79
  80
  81
  82
  83
  84
  85
  86
  87
  88
  89
  90
  91
  92
  93
  94
  95
  96
  97
  98
  99
 100
 101
 102
 103
 104
 105
 106
 107
 108
 109
 110
 111
 112
 113
 114
 115
 116
 117
 118
 119
 120
 121
 122
 123
 124
 125
 126
 127
 128
 129
 130
 131
 132
 133
 134
 135
 136
 137
 138
 139
 140
 141
 142
 143
 144
 145
 146
 147
 148
 149
 150
 151
 152
 153
 154
 155
 156
 157
 158
 159
 160
 161
 162
 163
 164
 165
 166
 167
 168
 169
 170
 171
 172
 173
 174
 175
 176
 177
 178
 179
 180
 181
 182
 183
 184
 185
 186
 187
 188
 189
 190
 191
 192
 193
 194
 195
 196
 197
 198
 199
 200
 201
 202
 203
 204
 205
 206
 207
 208
 209
 210
 211
 212
 213
 214
 215
 216
 217
 218
 219
 220
 221
 222
 223
 224
 225
 226
 227
 228
 229
 230
 231
 232
 233
 234
 235
 236
 237
 238
 239
 240
 241
 242
 243
 244
 245
 246
 247
 248
 249
 250
 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
 385
 386
 387
 388
 389
 390
 391
 392
 393
 394
 395
 396
 397
 398
 399
 400
 401
 402
 403
 404
 405
 406
 407
 408
 409
 410
 411
 412
 413
 414
 415
 416
 417
 418
 419
 420
 421
 422
 423
 424
 425
 426
 427
 428
 429
 430
 431
 432
 433
 434
 435
 436
 437
 438
 439
 440
 441
 442
 443
 444
 445
 446
 447
 448
 449
 450
 451
 452
 453
 454
 455
 456
 457
 458
 459
 460
 461
 462
 463
 464
 465
 466
 467
 468
 469
 470
 471
 472
 473
 474
 475
 476
 477
 478
 479
 480
 481
 482
 483
 484
 485
 486
 487
 488
 489
 490
 491
 492
 493
 494
 495
 496
 497
 498
 499
 500
 501
 502
 503
 504
 505
 506
 507
 508
 509
 510
 511
 512
 513
 514
 515
 516
 517
 518
 519
 520
 521
 522
 523
 524
 525
 526
 527
 528
 529
 530
 531
 532
 533
 534
 535
 536
 537
 538
 539
 540
 541
 542
 543
 544
 545
 546
 547
 548
 549
 550
 551
 552
 553
 554
 555
 556
 557
 558
 559
 560
 561
 562
 563
 564
 565
 566
 567
 568
 569
 570
 571
 572
 573
 574
 575
 576
 577
 578
 579
 580
 581
 582
 583
 584
 585
 586
 587
 588
 589
 590
 591
 592
 593
 594
 595
 596
 597
 598
 599
 600
 601
 602
 603
 604
 605
 606
 607
 608
 609
 610
 611
 612
 613
 614
 615
 616
 617
 618
 619
 620
 621
 622
 623
 624
 625
 626
 627
 628
 629
 630
 631
 632
 633
 634
 635
 636
 637
 638
 639
 640
 641
 642
 643
 644
 645
 646
 647
 648
 649
 650
 651
 652
 653
 654
 655
 656
 657
 658
 659
 660
 661
 662
 663
 664
 665
 666
 667
 668
 669
 670
 671
 672
 673
 674
 675
 676
 677
 678
 679
 680
 681
 682
 683
 684
 685
 686
 687
 688
 689
 690
 691
 692
 693
 694
 695
 696
 697
 698
 699
 700
 701
 702
 703
 704
 705
 706
 707
 708
 709
 710
 711
 712
 713
 714
 715
 716
 717
 718
 719
 720
 721
 722
 723
 724
 725
 726
 727
 728
 729
 730
 731
 732
 733
 734
 735
 736
 737
 738
 739
 740
 741
 742
 743
 744
 745
 746
 747
 748
 749
 750
 751
 752
 753
 754
 755
 756
 757
 758
 759
 760
 761
 762
 763
 764
 765
 766
 767
 768
 769
 770
 771
 772
 773
 774
 775
 776
 777
 778
 779
 780
 781
 782
 783
 784
 785
 786
 787
 788
 789
 790
 791
 792
 793
 794
 795
 796
 797
 798
 799
 800
 801
 802
 803
 804
 805
 806
 807
 808
 809
 810
 811
 812
 813
 814
 815
 816
 817
 818
 819
 820
 821
 822
 823
 824
 825
 826
 827
 828
 829
 830
 831
 832
 833
 834
 835
 836
 837
 838
 839
 840
 841
 842
 843
 844
 845
 846
 847
 848
 849
 850
 851
 852
 853
 854
 855
 856
 857
 858
 859
 860
 861
 862
 863
 864
 865
 866
 867
 868
 869
 870
 871
 872
 873
 874
 875
 876
 877
 878
 879
 880
 881
 882
 883
 884
 885
 886
 887
 888
 889
 890
 891
 892
 893
 894
 895
 896
 897
 898
 899
 900
 901
 902
 903
 904
 905
 906
 907
 908
 909
 910
 911
 912
 913
 914
 915
 916
 917
 918
 919
 920
 921
 922
 923
 924
 925
 926
 927
 928
 929
 930
 931
 932
 933
 934
 935
 936
 937
 938
 939
 940
 941
 942
 943
 944
 945
 946
 947
 948
 949
 950
 951
 952
 953
 954
 955
 956
 957
 958
 959
 960
 961
 962
 963
 964
 965
 966
 967
 968
 969
 970
 971
 972
 973
 974
 975
 976
 977
 978
 979
 980
 981
 982
 983
 984
 985
 986
 987
 988
 989
 990
 991
 992
 993
 994
 995
 996
 997
 998
 999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
#![warn(clippy::all)]
#![allow(
    clippy::too_many_arguments,
    clippy::cast_lossless,
    clippy::many_single_char_names
)]
#![cfg_attr(not(feature = "std"), no_std)]

extern crate alloc;

use alloc::vec::Vec;
use byteorder::{BigEndian as BE, ByteOrder};
use core::ops::Deref;

#[cfg(not(any(feature = "libm", feature = "std")))]
compile_error!("You need to activate either the `std` or `libm` feature.");

#[cfg(all(feature = "libm", not(feature = "std")))]
trait FloatExt {
    fn floor(self) -> Self;
    fn ceil(self) -> Self;
    fn sqrt(self) -> Self;
}
#[cfg(all(feature = "libm", not(feature = "std")))]
impl FloatExt for f32 {
    #[inline]
    fn floor(self) -> Self {
        libm::floorf(self)
    }
    #[inline]
    fn ceil(self) -> Self {
        libm::ceilf(self)
    }
    #[inline]
    fn sqrt(self) -> Self {
        libm::sqrtf(self)
    }
}

#[derive(Copy, Clone, Debug)]
pub struct FontInfo<Data: Deref<Target = [u8]>> {
    data: Data, // pointer to .ttf file
    // fontstart: usize,       // offset of start of font
    num_glyphs: u32, // number of glyphs, needed for range checking
    loca: u32,
    head: u32,
    glyf: u32,
    hhea: u32,
    hmtx: u32,
    name: u32,
    kern: u32,                // table locations as offset from start of .ttf
    index_map: u32,           // a cmap mapping for our chosen character encoding
    index_to_loc_format: u32, // format needed to map from glyph index to glyph
}

#[derive(Copy, Clone, Debug, PartialEq, Eq, Hash)]
#[repr(C)]
pub struct Vertex {
    pub x: i16,
    pub y: i16,
    pub cx: i16,
    pub cy: i16,
    type_: u8,
}

impl Vertex {
    pub fn vertex_type(&self) -> VertexType {
        match self.type_ {
            1 => VertexType::MoveTo,
            2 => VertexType::LineTo,
            3 => VertexType::CurveTo,
            type_ => panic!("Invalid vertex type: {}", type_),
        }
    }
}

#[test]
fn test_vertex_type() {
    fn v(type_: VertexType) -> Vertex {
        Vertex {
            x: 0,
            y: 0,
            cx: 0,
            cy: 0,
            type_: type_ as u8,
        }
    }
    assert_eq!(v(VertexType::MoveTo).vertex_type(), VertexType::MoveTo);
    assert_eq!(v(VertexType::LineTo).vertex_type(), VertexType::LineTo);
    assert_eq!(v(VertexType::CurveTo).vertex_type(), VertexType::CurveTo);
}

#[test]
#[should_panic]
fn test_invalid_vertex_type() {
    let v = Vertex {
        x: 0,
        y: 0,
        cx: 0,
        cy: 0,
        type_: 255,
    };
    let s = match v.vertex_type() {
        VertexType::MoveTo => "move to",
        VertexType::LineTo => "line to",
        VertexType::CurveTo => "curve to",
    };
    // With `Vertex::vertex_type` defined as `transmute` this would be undefined
    // behavior:
    println!("{}", s);
}

#[derive(Copy, Clone, Debug, PartialEq, Eq, Hash)]
#[repr(u8)]
pub enum VertexType {
    MoveTo = 1,
    LineTo = 2,
    CurveTo = 3,
}

#[derive(Copy, Clone, Debug, PartialEq, Eq, Hash)]
pub struct Rect<T> {
    pub x0: T,
    pub y0: T,
    pub x1: T,
    pub y1: T,
}

#[derive(Copy, Clone, Debug, PartialEq, Eq, Hash)]
pub struct HMetrics {
    pub advance_width: i32,
    pub left_side_bearing: i32,
}

#[derive(Copy, Clone, Debug, PartialEq, Eq, Hash)]
pub struct VMetrics {
    pub ascent: i32,
    pub descent: i32,
    pub line_gap: i32,
}

#[derive(Copy, Clone, Debug, PartialEq, Eq, PartialOrd, Ord, Hash)]
#[repr(C)]
pub enum PlatformId {
    // platformID
    Unicode = 0,
    Mac = 1,
    Iso = 2,
    Microsoft = 3,
}
fn platform_id(v: u16) -> Option<PlatformId> {
    use crate::PlatformId::*;
    match v {
        0 => Some(Unicode),
        1 => Some(Mac),
        2 => Some(Iso),
        3 => Some(Microsoft),
        _ => None,
    }
}

#[derive(Clone, Copy, Debug, PartialEq, Eq, PartialOrd, Ord, Hash)]
#[repr(C)]
#[allow(non_camel_case_types)]
pub enum UnicodeEid {
    // encodingID for PLATFORM_ID_UNICODE
    Unicode_1_0 = 0,
    Unicode_1_1 = 1,
    Iso_10646 = 2,
    Unicode_2_0_Bmp = 3,
    Unicode_2_0_Full = 4,
}
fn unicode_eid(v: u16) -> Option<UnicodeEid> {
    use crate::UnicodeEid::*;
    match v {
        0 => Some(Unicode_1_0),
        1 => Some(Unicode_1_1),
        2 => Some(Iso_10646),
        3 => Some(Unicode_2_0_Bmp),
        4 => Some(Unicode_2_0_Full),
        _ => None,
    }
}

#[derive(Clone, Copy, Debug, PartialEq, Eq, PartialOrd, Ord, Hash)]
#[repr(C)]
pub enum MicrosoftEid {
    // encodingID for PLATFORM_ID_MICROSOFT
    Symbol = 0,
    UnicodeBMP = 1,
    Shiftjis = 2,
    UnicodeFull = 10,
}
fn microsoft_eid(v: u16) -> Option<MicrosoftEid> {
    use crate::MicrosoftEid::*;
    match v {
        0 => Some(Symbol),
        1 => Some(UnicodeBMP),
        2 => Some(Shiftjis),
        10 => Some(UnicodeFull),
        _ => None,
    }
}

#[derive(Clone, Copy, Debug, PartialEq, Eq, PartialOrd, Ord, Hash)]
#[repr(C)]
pub enum MacEid {
    // encodingID for PLATFORM_ID_MAC; same as Script Manager codes
    Roman = 0,
    Arabic = 4,
    Japanese = 1,
    Hebrew = 5,
    ChineseTrad = 2,
    Greek = 6,
    Korean = 3,
    Russian = 7,
}
fn mac_eid(v: u16) -> Option<MacEid> {
    use crate::MacEid::*;
    match v {
        0 => Some(Roman),
        1 => Some(Japanese),
        2 => Some(ChineseTrad),
        3 => Some(Korean),
        4 => Some(Arabic),
        5 => Some(Hebrew),
        6 => Some(Greek),
        7 => Some(Russian),
        _ => None,
    }
}

#[derive(Clone, Copy, Debug, PartialEq, Eq, PartialOrd, Ord, Hash)]
#[repr(C)]
pub enum MicrosoftLang {
    // languageID for PLATFORM_ID_MICROSOFT; same as LCID...
    // problematic because there are e.g. 16 english LCIDs and 16 arabic LCIDs
    English = 0x0409,
    Italian = 0x0410,
    Chinese = 0x0804,
    Japanese = 0x0411,
    Dutch = 0x0413,
    Korean = 0x0412,
    French = 0x040c,
    Russian = 0x0419,
    German = 0x0407,
    // Spanish = 0x0409,
    Hebrew = 0x040d,
    Swedish = 0x041D,
}
fn microsoft_lang(v: u16) -> Option<MicrosoftLang> {
    use crate::MicrosoftLang::*;
    match v {
        0x0409 => Some(English),
        0x0804 => Some(Chinese),
        0x0413 => Some(Dutch),
        0x040c => Some(French),
        0x0407 => Some(German),
        0x040d => Some(Hebrew),
        0x0410 => Some(Italian),
        0x0411 => Some(Japanese),
        0x0412 => Some(Korean),
        0x0419 => Some(Russian),
        0x041D => Some(Swedish),
        _ => None,
    }
}

#[derive(Clone, Copy, Debug, PartialEq, Eq, PartialOrd, Ord, Hash)]
#[repr(C)]
pub enum MacLang {
    // languageID for PLATFORM_ID_MAC
    English = 0,
    Japanese = 11,
    Arabic = 12,
    Korean = 23,
    Dutch = 4,
    Russian = 32,
    French = 1,
    Spanish = 6,
    German = 2,
    Swedish = 5,
    Hebrew = 10,
    ChineseSimplified = 33,
    Italian = 3,
    ChineseTrad = 19,
}
fn mac_lang(v: u16) -> Option<MacLang> {
    use crate::MacLang::*;
    match v {
        0 => Some(English),
        12 => Some(Arabic),
        4 => Some(Dutch),
        1 => Some(French),
        2 => Some(German),
        10 => Some(Hebrew),
        3 => Some(Italian),
        11 => Some(Japanese),
        23 => Some(Korean),
        32 => Some(Russian),
        6 => Some(Spanish),
        5 => Some(Swedish),
        33 => Some(ChineseSimplified),
        19 => Some(ChineseTrad),
        _ => None,
    }
}

#[derive(Clone, Copy, Debug, PartialEq, Eq, PartialOrd, Ord, Hash)]
pub enum PlatformEncodingLanguageId {
    Unicode(Option<Result<UnicodeEid, u16>>, Option<u16>),
    Mac(Option<Result<MacEid, u16>>, Option<Result<MacLang, u16>>),
    Iso(Option<u16>, Option<u16>),
    Microsoft(
        Option<Result<MicrosoftEid, u16>>,
        Option<Result<MicrosoftLang, u16>>,
    ),
}
fn platform_encoding_id(
    platform_id: PlatformId,
    encoding_id: Option<u16>,
    language_id: Option<u16>,
) -> PlatformEncodingLanguageId {
    match platform_id {
        PlatformId::Unicode => PlatformEncodingLanguageId::Unicode(
            encoding_id.map(|id| unicode_eid(id).ok_or(id)),
            language_id,
        ),
        PlatformId::Mac => PlatformEncodingLanguageId::Mac(
            encoding_id.map(|id| mac_eid(id).ok_or(id)),
            language_id.map(|id| mac_lang(id).ok_or(id)),
        ),
        PlatformId::Iso => PlatformEncodingLanguageId::Iso(encoding_id, language_id),
        PlatformId::Microsoft => PlatformEncodingLanguageId::Microsoft(
            encoding_id.map(|id| microsoft_eid(id).ok_or(id)),
            language_id.map(|id| microsoft_lang(id).ok_or(id)),
        ),
    }
}

// # accessors to parse data from file

// on platforms that don't allow misaligned reads, if we want to allow
// truetype fonts that aren't padded to alignment, define
// ALLOW_UNALIGNED_TRUETYPE

/// Return `true` if `data` holds a font stored in a format this crate
/// recognizes, according to its signature in the initial bytes.
pub fn is_font(data: &[u8]) -> bool {
    if data.len() >= 4 {
        let tag = &data[0..4];
        tag == [b'1', 0, 0, 0] || tag == b"typ1" || tag == b"OTTO" || tag == [0, 1, 0, 0]
    } else {
        false
    }
}

/// Return `true` if `data` holds a TrueType Collection, according to its
/// signature in the initial bytes. A TrueType Collection stores several fonts
/// in a single file, allowing them to share data for glyphs they have in
/// common.
pub fn is_collection(data: &[u8]) -> bool {
    data.len() >= 4 && &data[0..4] == b"ttcf"
}

fn find_table(data: &[u8], fontstart: usize, tag: &[u8]) -> u32 {
    let num_tables = BE::read_u16(&data[fontstart + 4..]);
    let tabledir = fontstart + 12;
    for i in 0..num_tables {
        let loc = tabledir + 16 * (i as usize);
        if &data[loc..loc + 4] == tag {
            return BE::read_u32(&data[loc + 8..]);
        }
    }
    0
}

/// Each .ttf/.ttc file may have more than one font. Each font has a sequential
/// index number starting from 0. Call this function to get the font offset for
/// a given index; it returns None if the index is out of range. A regular .ttf
/// file will only define one font and it always be at offset 0, so it will
/// return Some(0) for index 0, and None for all other indices. You can just
/// skip this step if you know it's that kind of font.
pub fn get_font_offset_for_index(font_collection: &[u8], index: i32) -> Option<u32> {
    // if it's just a font, there's only one valid index
    if is_font(font_collection) {
        return if index == 0 { Some(0) } else { None };
    }
    // check if it's a TTC
    if is_collection(font_collection)
        && (BE::read_u32(&font_collection[4..]) == 0x0001_0000
            || BE::read_u32(&font_collection[4..]) == 0x0002_0000)
    {
        let n = BE::read_i32(&font_collection[8..]);
        if index >= n {
            return None;
        }
        return Some(BE::read_u32(&font_collection[12 + (index as usize) * 4..]));
    }
    None
}

macro_rules! read_ints {
    ($n:expr, i16, $data:expr) => {{
        let mut nums = [0; $n];
        let data = $data;
        BE::read_i16_into(&data[..$n * 2], &mut nums);
        nums
    }};
    ($n:expr, u16, $data:expr) => {{
        let mut nums = [0; $n];
        let data = $data;
        BE::read_u16_into(&data[..$n * 2], &mut nums);
        nums
    }};
    ($n:expr, u32, $data:expr) => {{
        let mut nums = [0; $n];
        let data = $data;
        BE::read_u32_into(&data[..$n * 4], &mut nums);
        nums
    }};
}

impl<Data: Deref<Target = [u8]>> FontInfo<Data> {
    /// Given an offset into the file that defines a font, this function builds
    /// the necessary cached info for the rest of the system.
    pub fn new(data: Data, fontstart: usize) -> Option<FontInfo<Data>> {
        let cmap = find_table(&data, fontstart, b"cmap"); // required
        let loca = find_table(&data, fontstart, b"loca"); // required
        let head = find_table(&data, fontstart, b"head"); // required
        let glyf = find_table(&data, fontstart, b"glyf"); // required
        let hhea = find_table(&data, fontstart, b"hhea"); // required
        let hmtx = find_table(&data, fontstart, b"hmtx"); // required
        let name = find_table(&data, fontstart, b"name"); // not required
        let kern = find_table(&data, fontstart, b"kern"); // not required
        if cmap == 0 || loca == 0 || head == 0 || glyf == 0 || hhea == 0 || hmtx == 0 {
            return None;
        }
        let t = find_table(&data, fontstart, b"maxp");
        let num_glyphs = if t != 0 {
            BE::read_u16(&data[t as usize + 4..])
        } else {
            0xffff
        };

        // find a cmap encoding table we understand *now* to avoid searching
        // later. (todo: could make this installable)
        // the same regardless of glyph.
        let num_tables = BE::read_u16(&data[cmap as usize + 2..]);
        let mut index_map = 0;
        for i in 0..num_tables {
            let encoding_record = (cmap + 4 + 8 * (i as u32)) as usize;
            // find an encoding we understand:
            match platform_id(BE::read_u16(&data[encoding_record..])) {
                Some(PlatformId::Microsoft) => {
                    match microsoft_eid(BE::read_u16(&data[encoding_record + 2..])) {
                        Some(MicrosoftEid::UnicodeBMP) | Some(MicrosoftEid::UnicodeFull) => {
                            // MS/Unicode
                            index_map = cmap + BE::read_u32(&data[encoding_record + 4..]);
                        }
                        _ => (),
                    }
                }
                Some(PlatformId::Unicode) => {
                    // Mac/iOS has these
                    // all the encodingIDs are unicode, so we don't bother to check it
                    index_map = cmap + BE::read_u32(&data[encoding_record + 4..]);
                }
                _ => (),
            }
        }
        if index_map == 0 {
            return None;
        }
        let index_to_loc_format = BE::read_u16(&data[head as usize + 50..]) as u32;
        Some(FontInfo {
            // fontstart: fontstart,
            data,
            loca,
            head,
            glyf,
            hhea,
            hmtx,
            name,
            kern,
            num_glyphs: num_glyphs as u32,
            index_map,
            index_to_loc_format,
        })
    }

    pub fn get_num_glyphs(&self) -> u32 {
        self.num_glyphs
    }

    /// If you're going to perform multiple operations on the same character
    /// and you want a speed-up, call this function with the character you're
    /// going to process, then use glyph-based functions instead of the
    /// codepoint-based functions.
    pub fn find_glyph_index(&self, unicode_codepoint: u32) -> u32 {
        let data = &self.data;
        let index_map = &data[self.index_map as usize..]; //self.index_map as usize;

        let format = BE::read_u16(index_map);
        match format {
            0 => {
                // apple byte encoding
                let bytes = BE::read_u16(&index_map[2..]);
                if unicode_codepoint < bytes as u32 - 6 {
                    return index_map[6 + unicode_codepoint as usize] as u32;
                }
                0
            }
            6 => {
                let first = BE::read_u16(&index_map[6..]) as u32;
                let count = BE::read_u16(&index_map[8..]) as u32;
                if unicode_codepoint >= first && unicode_codepoint < first + count {
                    return BE::read_u16(&index_map[10 + (unicode_codepoint - first) as usize * 2..])
                        as u32;
                }
                0
            }
            2 => {
                // @TODO: high-byte mapping for japanese/chinese/korean
                panic!("Index map format unsupported: 2");
            }
            4 => {
                // standard mapping for windows fonts: binary search collection of ranges
                let segcount = BE::read_u16(&index_map[6..]) as usize >> 1;
                let mut search_range = BE::read_u16(&index_map[8..]) as usize >> 1;
                let mut entry_selector = BE::read_u16(&index_map[10..]);
                let range_shift = BE::read_u16(&index_map[12..]) as usize >> 1;

                // do a binary search of the segments
                let end_count = self.index_map as usize + 14;
                let mut search = end_count;

                if unicode_codepoint > 0xffff {
                    return 0;
                }

                // they lie from endCount .. endCount + segCount
                // but searchRange is the nearest power of two, so...
                if unicode_codepoint >= BE::read_u16(&data[search + range_shift * 2..]) as u32 {
                    search += range_shift * 2;
                }

                // now decrement to bias correctly to find smallest
                search -= 2;
                while entry_selector != 0 {
                    search_range >>= 1;
                    let end = BE::read_u16(&data[search + search_range * 2..]) as u32;
                    if unicode_codepoint > end {
                        search += search_range * 2;
                    }
                    entry_selector -= 1;
                }
                search += 2;

                {
                    let item = (search - end_count) >> 1;
                    assert!(
                        unicode_codepoint <= BE::read_u16(&data[end_count + 2 * item..]) as u32
                    );
                    let start = BE::read_u16(&index_map[14 + segcount * 2 + 2 + 2 * item..]) as u32;
                    if unicode_codepoint < start {
                        return 0;
                    }
                    let offset =
                        BE::read_u16(&index_map[14 + segcount * 6 + 2 + 2 * item..]) as usize;
                    if offset == 0 {
                        return (unicode_codepoint as i32
                            + BE::read_i16(&index_map[14 + segcount * 4 + 2 + 2 * item..]) as i32)
                            as u16 as u32;
                    }
                    BE::read_u16(
                        &index_map[offset
                            + (unicode_codepoint - start) as usize * 2
                            + 14
                            + segcount * 6
                            + 2
                            + 2 * item..],
                    ) as u32
                }
            }
            12 | 13 => {
                let mut low = 0u32;
                let mut high = BE::read_u32(&index_map[12..]);
                let groups = &index_map[16..];

                // Binary search of the right group
                while low < high {
                    let mid = (low + high) / 2; // rounds down, so low <= mid < high
                    let mid12 = (mid * 12) as usize;
                    let group = &groups[mid12..mid12 + 12];
                    let start_char = BE::read_u32(group);
                    if unicode_codepoint < start_char {
                        high = mid;
                    } else if unicode_codepoint > BE::read_u32(&group[4..]) {
                        low = mid + 1;
                    } else {
                        let start_glyph = BE::read_u32(&group[8..]);
                        if format == 12 {
                            return start_glyph + unicode_codepoint - start_char;
                        } else {
                            return start_glyph;
                        }
                    }
                }

                0
            }
            n => panic!("Index map format unsupported: {}", n),
        }
    }

    /// Returns the series of vertices encoding the shape of the glyph for this
    /// codepoint.
    ///
    /// The shape is a series of countours. Each one starts with
    /// a moveto, then consists of a series of mixed
    /// lineto and curveto segments. A lineto
    /// draws a line from previous endpoint to its x,y; a curveto
    /// draws a quadratic bezier from previous endpoint to
    /// its x,y, using cx,cy as the bezier control point.
    pub fn get_codepoint_shape(&self, unicode_codepoint: u32) -> Option<Vec<Vertex>> {
        self.get_glyph_shape(self.find_glyph_index(unicode_codepoint))
    }

    fn get_glyf_offset(&self, glyph_index: u32) -> Option<u32> {
        if glyph_index >= self.num_glyphs || self.index_to_loc_format >= 2 {
            // glyph index out of range or unknown index->glyph map format
            return None;
        }

        let [g1, g2] = if self.index_to_loc_format == 0 {
            let d = &self.data[(self.loca + glyph_index * 2) as usize..];
            let [g1, g2] = read_ints!(2, u16, d);
            [g1 as u32 * 2, g2 as u32 * 2]
        } else {
            read_ints!(2, u32, &self.data[(self.loca + glyph_index * 4) as usize..])
        };
        if g1 == g2 {
            None
        } else {
            Some(self.glyf + g1)
        }
    }

    /// Like `get_codepoint_box`, but takes a glyph index. Use this if you have
    /// cached the glyph index for a codepoint.
    pub fn get_glyph_box(&self, glyph_index: u32) -> Option<Rect<i16>> {
        let g = self.get_glyf_offset(glyph_index)? as usize;
        let [x0, y0, x1, y1] = read_ints!(4, i16, &self.data[g + 2..]);
        Some(Rect { x0, y0, x1, y1 })
    }

    /// Gets the bounding box of the visible part of the glyph, in unscaled
    /// coordinates
    pub fn get_codepoint_box(&self, codepoint: u32) -> Option<Rect<i16>> {
        self.get_glyph_box(self.find_glyph_index(codepoint))
    }

    /// returns true if nothing is drawn for this glyph
    pub fn is_glyph_empty(&self, glyph_index: u32) -> bool {
        match self.get_glyf_offset(glyph_index) {
            Some(g) => {
                let number_of_contours = BE::read_i16(&self.data[g as usize..]);
                number_of_contours == 0
            }
            None => true,
        }
    }

    /// Like `get_codepoint_shape`, but takes a glyph index instead. Use this
    /// if you have cached the glyph index for a codepoint.
    pub fn get_glyph_shape(&self, glyph_index: u32) -> Option<Vec<Vertex>> {
        let g = match self.get_glyf_offset(glyph_index) {
            Some(g) => &self.data[g as usize..],
            None => return None,
        };

        let number_of_contours = BE::read_i16(g);
        let vertices: Vec<Vertex> = if number_of_contours > 0 {
            self.glyph_shape_positive_contours(g, number_of_contours as usize)
        } else if number_of_contours == -1 {
            // Compound shapes
            let mut more = true;
            let mut comp = &g[10..];
            let mut vertices = Vec::new();
            while more {
                let mut mtx = [1.0, 0.0, 0.0, 1.0, 0.0, 0.0];

                let [flags, gidx] = read_ints!(2, i16, comp);
                comp = &comp[4..];
                let gidx = gidx as u16;

                if flags & 2 != 0 {
                    // XY values
                    if flags & 1 != 0 {
                        // shorts
                        let [a, b] = read_ints!(2, i16, comp);
                        comp = &comp[4..];
                        mtx[4] = a as f32;
                        mtx[5] = b as f32;
                    } else {
                        mtx[4] = (comp[0] as i8) as f32;
                        mtx[5] = (comp[1] as i8) as f32;
                        comp = &comp[2..];
                    }
                } else {
                    panic!("Matching points not supported.");
                }
                if flags & (1 << 3) != 0 {
                    // WE_HAVE_A_SCALE
                    mtx[0] = BE::read_i16(comp) as f32 / 16384.0;
                    comp = &comp[2..];
                    mtx[1] = 0.0;
                    mtx[2] = 0.0;
                    mtx[3] = mtx[0];
                } else if flags & (1 << 6) != 0 {
                    // WE_HAVE_AN_X_AND_YSCALE
                    let [a, b] = read_ints!(2, i16, comp);
                    comp = &comp[4..];
                    mtx[0] = a as f32 / 16384.0;
                    mtx[1] = 0.0;
                    mtx[2] = 0.0;
                    mtx[3] = b as f32 / 16384.0;
                } else if flags & (1 << 7) != 0 {
                    // WE_HAVE_A_TWO_BY_TWO
                    let [a, b, c, d] = read_ints!(4, i16, comp);
                    comp = &comp[8..];
                    mtx[0] = a as f32 / 16384.0;
                    mtx[1] = b as f32 / 16384.0;
                    mtx[2] = c as f32 / 16384.0;
                    mtx[3] = d as f32 / 16384.0;
                }

                // Find transformation scales.
                let m = (mtx[0] * mtx[0] + mtx[1] * mtx[1]).sqrt();
                let n = (mtx[2] * mtx[2] + mtx[3] * mtx[3]).sqrt();

                // Get indexed glyph.
                let mut comp_verts = self.get_glyph_shape(gidx as u32).unwrap_or_else(Vec::new);
                if !comp_verts.is_empty() {
                    // Transform vertices
                    for v in &mut *comp_verts {
                        let (x, y, cx, cy) = (v.x as f32, v.y as f32, v.cx as f32, v.cy as f32);
                        *v = Vertex {
                            type_: v.type_,
                            x: (m * (mtx[0] * x + mtx[2] * y + mtx[4])) as i16,
                            y: (n * (mtx[1] * x + mtx[3] * y + mtx[5])) as i16,
                            cx: (m * (mtx[0] * cx + mtx[2] * cy + mtx[4])) as i16,
                            cy: (n * (mtx[1] * cx + mtx[3] * cy + mtx[5])) as i16,
                        };
                    }
                    // Append vertices.
                    vertices.append(&mut comp_verts);
                }
                // More components ?
                more = flags & (1 << 5) != 0;
            }
            vertices
        } else if number_of_contours < 0 {
            panic!("Contour format not supported.")
        } else {
            return None;
        };
        Some(vertices)
    }

    #[inline]
    fn glyph_shape_positive_contours(
        &self,
        glyph_data: &[u8],
        number_of_contours: usize,
    ) -> Vec<Vertex> {
        use crate::VertexType::*;

        struct FlagData {
            flags: u8,
            x: i16,
            y: i16,
        }

        #[inline]
        fn close_shape(
            vertices: &mut Vec<Vertex>,
            was_off: bool,
            start_off: bool,
            sx: i16,
            sy: i16,
            scx: i16,
            scy: i16,
            cx: i16,
            cy: i16,
        ) {
            if start_off {
                if was_off {
                    vertices.push(Vertex {
                        type_: CurveTo as u8,
                        x: (cx + scx) >> 1,
                        y: (cy + scy) >> 1,
                        cx,
                        cy,
                    });
                }
                vertices.push(Vertex {
                    type_: CurveTo as u8,
                    x: sx,
                    y: sy,
                    cx: scx,
                    cy: scy,
                });
            } else {
                vertices.push(if was_off {
                    Vertex {
                        type_: CurveTo as u8,
                        x: sx,
                        y: sy,
                        cx,
                        cy,
                    }
                } else {
                    Vertex {
                        type_: LineTo as u8,
                        x: sx,
                        y: sy,
                        cx: 0,
                        cy: 0,
                    }
                });
            }
        }

        let number_of_contours = number_of_contours as usize;
        let mut start_off = false;
        let mut was_off = false;
        let end_points_of_contours = &glyph_data[10..];
        let ins = BE::read_u16(&glyph_data[10 + number_of_contours * 2..]) as usize;
        let mut points = &glyph_data[10 + number_of_contours * 2 + 2 + ins..];

        let n = 1 + BE::read_u16(&end_points_of_contours[number_of_contours * 2 - 2..]) as usize;

        let m = n + 2 * number_of_contours; // a loose bound on how many vertices we might need
        let mut vertices: Vec<Vertex> = Vec::with_capacity(m);

        let mut flag_data = Vec::with_capacity(n);

        let mut next_move = 0;

        // in first pass, we load uninterpreted data into the allocated array above

        // first load flags
        {
            let mut flagcount = 0;
            let mut flags = 0;
            for _ in 0..n {
                if flagcount == 0 {
                    flags = points[0];
                    if flags & 8 != 0 {
                        flagcount = points[1];
                        points = &points[2..];
                    } else {
                        points = &points[1..];
                    }
                } else {
                    flagcount -= 1;
                }
                flag_data.push(FlagData { flags, x: 0, y: 0 });
            }
        }

        // now load x coordinates
        let mut x_coord = 0_i16;
        for flag_data in &mut flag_data {
            let flags = flag_data.flags;
            if flags & 2 != 0 {
                let dx = i16::from(points[0]);
                points = &points[1..];
                if flags & 16 != 0 {
                    // ???
                    x_coord += dx;
                } else {
                    x_coord -= dx;
                }
            } else if flags & 16 == 0 {
                x_coord += BE::read_i16(points);
                points = &points[2..];
            }
            flag_data.x = x_coord;
        }

        // now load y coordinates
        let mut y_coord = 0_i16;
        for flag_data in &mut flag_data {
            let flags = flag_data.flags;
            if flags & 4 != 0 {
                let dy = i16::from(points[0]);
                points = &points[1..];
                if flags & 32 != 0 {
                    y_coord += dy;
                } else {
                    y_coord -= dy;
                }
            } else if flags & 32 == 0 {
                y_coord += BE::read_i16(points);
                points = &points[2..];
            }
            flag_data.y = y_coord;
        }

        // now convert them to our format
        let mut sx = 0;
        let mut sy = 0;
        let mut cx = 0;
        let mut cy = 0;
        let mut scx = 0;
        let mut scy = 0;
        let mut j = 0;

        let mut iter = flag_data.into_iter().enumerate().peekable();

        while let Some((index, FlagData { flags, x, y })) = iter.next() {
            if next_move == index {
                if index != 0 {
                    close_shape(&mut vertices, was_off, start_off, sx, sy, scx, scy, cx, cy);
                }

                // now start the new one
                start_off = flags & 1 == 0;
                if start_off {
                    // if we start off with an off-curve point, then when we need to find a
                    // point on the curve where we can start, and we
                    // need to save some state for
                    // when we wraparound.
                    scx = x;
                    scy = y;

                    let (next_flags, next_x, next_y) = match iter.peek() {
                        Some((_, fd)) => (fd.flags, fd.x, fd.y),
                        None => break,
                    };

                    if next_flags & 1 == 0 {
                        // next point is also a curve point, so interpolate an on-point curve
                        sx = (x + next_x) >> 1;
                        sy = (y + next_y) >> 1;
                    } else {
                        // otherwise just use the next point as our start point
                        sx = next_x;
                        sy = next_y;

                        // we're using point i+1 as the starting point, so skip it
                        let _ = iter.next();
                    }
                } else {
                    sx = x;
                    sy = y;
                }
                vertices.push(Vertex {
                    type_: MoveTo as u8,
                    x: sx,
                    y: sy,
                    cx: 0,
                    cy: 0,
                });
                was_off = false;
                next_move = 1 + BE::read_u16(&end_points_of_contours[j * 2..]) as usize;
                j += 1;
            } else if flags & 1 == 0 {
                // if it's a curve
                if was_off {
                    // two off-curve control points in a row means interpolate an on-curve
                    // midpoint
                    vertices.push(Vertex {
                        type_: CurveTo as u8,
                        x: ((cx + x) >> 1),
                        y: ((cy + y) >> 1),
                        cx,
                        cy,
                    });
                }
                cx = x;
                cy = y;
                was_off = true;
            } else {
                vertices.push(if was_off {
                    Vertex {
                        type_: CurveTo as u8,
                        x,
                        y,
                        cx,
                        cy,
                    }
                } else {
                    Vertex {
                        type_: LineTo as u8,
                        x,
                        y,
                        cx: 0,
                        cy: 0,
                    }
                });
                was_off = false;
            }
        }
        close_shape(
            &mut vertices,
            // &mut num_vertices,
            was_off,
            start_off,
            sx,
            sy,
            scx,
            scy,
            cx,
            cy,
        );

        vertices
    }

    /// like `get_codepoint_h_metrics`, but takes a glyph index instead. Use
    /// this if you have cached the glyph index for a codepoint.
    pub fn get_glyph_h_metrics(&self, glyph_index: u32) -> HMetrics {
        let num_of_long_hor_metrics = BE::read_u16(&self.data[self.hhea as usize + 34..]) as usize;
        let glyph_index = glyph_index as usize;
        if glyph_index < num_of_long_hor_metrics {
            let data = &self.data[self.hmtx as usize + 4 * glyph_index..];
            let [advance_width, left_side_bearing] = read_ints!(2, i16, data);
            HMetrics {
                advance_width: i32::from(advance_width),
                left_side_bearing: i32::from(left_side_bearing),
            }
        } else {
            HMetrics {
                advance_width: BE::read_i16(
                    &self.data[self.hmtx as usize + 4 * (num_of_long_hor_metrics - 1)..],
                ) as i32,
                left_side_bearing: BE::read_i16(
                    &self.data[self.hmtx as usize
                        + 4 * num_of_long_hor_metrics
                        + 2 * (glyph_index as isize - num_of_long_hor_metrics as isize) as usize..],
                ) as i32,
            }
        }
    }

    /// like `get_codepoint_kern_advance`, but takes glyph indices instead. Use
    /// this if you have cached the glyph indices for the codepoints.
    pub fn get_glyph_kern_advance(&self, glyph_1: u32, glyph_2: u32) -> i32 {
        let kern = &self.data[self.kern as usize..];
        // we only look at the first table. it must be 'horizontal' and format 0
        if self.kern == 0 || BE::read_u16(&kern[2..]) < 1 || BE::read_u16(&kern[8..]) != 1 {
            // kern not present, OR
            // no tables (need at least one), OR
            // horizontal flag not set in format
            return 0;
        }

        let mut l: i32 = 0;
        let mut r: i32 = BE::read_u16(&kern[10..]) as i32 - 1;
        let needle = glyph_1 << 16 | glyph_2;
        while l <= r {
            let m = (l + r) >> 1;
            let straw = BE::read_u32(&kern[18 + (m as usize) * 6..]); // note: unaligned read
            if needle < straw {
                r = m - 1;
            } else if needle > straw {
                l = m + 1;
            } else {
                return BE::read_i16(&kern[22 + (m as usize) * 6..]) as i32;
            }
        }
        0
    }

    /// an additional amount to add to the 'advance' value between cp1 and cp2
    pub fn get_codepoint_kern_advance(&self, cp1: u32, cp2: u32) -> i32 {
        if self.kern == 0 {
            // if no kerning table, don't waste time looking up both codepoint->glyphs
            0
        } else {
            self.get_glyph_kern_advance(self.find_glyph_index(cp1), self.find_glyph_index(cp2))
        }
    }

    /// `left_side_bearing` is the offset from the current horizontal position
    /// to the left edge of the character `advance_width` is the offset
    /// from the current horizontal position to the next horizontal
    /// position these are
    /// expressed in unscaled
    /// coordinates
    pub fn get_codepoint_h_metrics(&self, codepoint: u32) -> HMetrics {
        self.get_glyph_h_metrics(self.find_glyph_index(codepoint))
    }

    /// `ascent` is the coordinate above the baseline the font extends; descent
    /// is the coordinate below the baseline the font extends (i.e. it is
    /// typically negative) `line_gap` is the spacing between one row's
    /// descent and the next row's ascent... so you should advance the
    /// vertical position by `ascent -
    /// descent + line_gap` these are expressed in unscaled coordinates, so
    /// you must multiply by the scale factor for a given size
    pub fn get_v_metrics(&self) -> VMetrics {
        let hhea = &self.data[self.hhea as usize..];
        let [ascent, descent, line_gap] = read_ints!(3, i16, &hhea[4..]);
        VMetrics {
            ascent: i32::from(ascent),
            descent: i32::from(descent),
            line_gap: i32::from(line_gap),
        }
    }

    /// the bounding box around all possible characters
    pub fn get_bounding_box(&self) -> Rect<i16> {
        let head = &self.data[self.head as usize..];
        Rect {
            x0: BE::read_i16(&head[36..]),
            y0: BE::read_i16(&head[38..]),
            x1: BE::read_i16(&head[40..]),
            y1: BE::read_i16(&head[42..]),
        }
    }

    /// computes a scale factor to produce a font whose "height" is 'pixels'
    /// tall. Height is measured as the distance from the highest ascender
    /// to the lowest descender; in other words, it's equivalent to calling
    /// GetFontVMetrics and computing:
    ///       scale = pixels / (ascent - descent)
    /// so if you prefer to measure height by the ascent only, use a similar
    /// calculation.
    pub fn scale_for_pixel_height(&self, height: f32) -> f32 {
        let hhea = &self.data[self.hhea as usize..];
        let fheight = {
            let [a, b] = read_ints!(2, i16, &hhea[4..]);
            f32::from(a) - f32::from(b)
        };
        height / fheight
    }

    /// Returns the units per EM square of this font.
    pub fn units_per_em(&self) -> u16 {
        BE::read_u16(&self.data[self.head as usize + 18..])
    }

    /// computes a scale factor to produce a font whose EM size is mapped to
    /// `pixels` tall. This is probably what traditional APIs compute, but
    /// I'm not positive.
    pub fn scale_for_mapping_em_to_pixels(&self, pixels: f32) -> f32 {
        pixels / (self.units_per_em() as f32)
    }

    /// like `get_codepoint_bitmap_box_subpixel`, but takes a glyph index
    /// instead of a codepoint.
    pub fn get_glyph_bitmap_box_subpixel(
        &self,
        glyph: u32,
        scale_x: f32,
        scale_y: f32,
        shift_x: f32,
        shift_y: f32,
    ) -> Option<Rect<i32>> {
        if let Some(glyph_box) = self.get_glyph_box(glyph) {
            // move to integral bboxes (treating pixels as little squares, what pixels get
            // touched?)
            Some(Rect {
                x0: (glyph_box.x0 as f32 * scale_x + shift_x).floor() as i32,
                y0: (-glyph_box.y1 as f32 * scale_y + shift_y).floor() as i32,
                x1: (glyph_box.x1 as f32 * scale_x + shift_x).ceil() as i32,
                y1: (-glyph_box.y0 as f32 * scale_y + shift_y).ceil() as i32,
            })
        } else {
            // e.g. space character
            None
        }
    }

    /// like `get_codepoint_bitmap_box`, but takes a glyph index instead of a
    /// codepoint.
    pub fn get_glyph_bitmap_box(
        &self,
        glyph: u32,
        scale_x: f32,
        scale_y: f32,
    ) -> Option<Rect<i32>> {
        self.get_glyph_bitmap_box_subpixel(glyph, scale_x, scale_y, 0.0, 0.0)
    }

    /// same as get_codepoint_bitmap_box, but you can specify a subpixel
    /// shift for the character
    pub fn get_codepoint_bitmap_box_subpixel(
        &self,
        codepoint: u32,
        scale_x: f32,
        scale_y: f32,
        shift_x: f32,
        shift_y: f32,
    ) -> Option<Rect<i32>> {
        self.get_glyph_bitmap_box_subpixel(
            self.find_glyph_index(codepoint),
            scale_x,
            scale_y,
            shift_x,
            shift_y,
        )
    }

    /// get the bounding box of the bitmap centered around the glyph origin; so
    /// the bitmap width is x1-x0, height is y1-y0, and location to place
    /// the bitmap top left is (left_side_bearing*scale, y0).
    /// (Note that the bitmap uses y-increases-down, but the shape uses
    /// y-increases-up, so CodepointBitmapBox and CodepointBox are inverted.)
    pub fn get_codepoint_bitmap_box(
        &self,
        codepoint: u32,
        scale_x: f32,
        scale_y: f32,
    ) -> Option<Rect<i32>> {
        self.get_codepoint_bitmap_box_subpixel(codepoint, scale_x, scale_y, 0.0, 0.0)
    }

    pub fn get_font_name_strings(&self) -> FontNameIter<'_, Data> {
        let nm = self.name as usize;
        if nm == 0 {
            return FontNameIter {
                font_info: &self,
                string_offset: 0,
                index: 0,
                count: 0,
            };
        }
        let count = BE::read_u16(&self.data[nm + 2..]) as usize;
        let string_offset = nm + BE::read_u16(&self.data[nm + 4..]) as usize;

        FontNameIter {
            font_info: &self,
            string_offset,
            index: 0,
            count,
        }
    }
}

#[derive(Clone, Copy, Debug)]
pub struct FontNameIter<'a, Data: Deref<Target = [u8]>> {
    /// Font info.
    font_info: &'a FontInfo<Data>,
    string_offset: usize,
    /// Next index.
    index: usize,
    /// Number of name strings.
    count: usize,
}

impl<'a, Data: 'a + Deref<Target = [u8]>> Iterator for FontNameIter<'a, Data> {
    type Item = (&'a [u8], Option<PlatformEncodingLanguageId>, u16);

    fn next(&mut self) -> Option<Self::Item> {
        if self.index >= self.count {
            return None;
        }

        let loc = self.font_info.name as usize + 6 + 12 * self.index;

        let pl_id = platform_id(BE::read_u16(&self.font_info.data[loc..]));
        let platform_encoding_language_id = pl_id.map(|pl_id| {
            let encoding_id = BE::read_u16(&self.font_info.data[loc + 2..]);
            let language_id = BE::read_u16(&self.font_info.data[loc + 4..]);
            platform_encoding_id(pl_id, Some(encoding_id), Some(language_id))
        });
        // @TODO: Define an enum type for Name ID.
        //        See https://www.microsoft.com/typography/otspec/name.htm, "Name IDs" section.
        let name_id = BE::read_u16(&self.font_info.data[loc + 6..]);
        let length = BE::read_u16(&self.font_info.data[loc + 8..]) as usize;
        let offset = self.string_offset + BE::read_u16(&self.font_info.data[loc + 10..]) as usize;

        self.index += 1;

        Some((
            &self.font_info.data[offset..offset + length],
            platform_encoding_language_id,
            name_id,
        ))
    }

    fn size_hint(&self) -> (usize, Option<usize>) {
        let remaining = self.count - self.index;
        (remaining, Some(remaining))
    }

    fn count(self) -> usize {
        self.count - self.index
    }

    fn last(mut self) -> Option<Self::Item> {
        if self.index >= self.count || self.count == 0 {
            return None;
        }
        self.index = self.count - 1;
        self.next()
    }

    fn nth(&mut self, n: usize) -> Option<Self::Item> {
        if n > self.count - self.index {
            self.index = self.count;
            return None;
        }
        self.index += n;
        self.next()
    }
}