Skip to main content

harfrust/hb/
algs.rs

1// FLAG macro in harfbuzz.
2#[inline]
3pub const fn rb_flag(x: u32) -> u32 {
4    1 << x
5}
6
7// FLAG_UNSAFE macro in harfbuzz.
8#[inline]
9pub fn rb_flag_unsafe(x: u32) -> u32 {
10    if x < 32 {
11        1 << x
12    } else {
13        0
14    }
15}
16
17// FLAG_RANGE macro in harfbuzz.
18#[inline]
19pub fn rb_flag_range(x: u32, y: u32) -> u32 {
20    (x < y) as u32 + rb_flag(y + 1) - rb_flag(x)
21}
22
23// FLAG64 macro in harfbuzz.
24#[inline]
25pub const fn rb_flag64(x: u32) -> u64 {
26    1 << x as u64
27}
28
29// FLAG64_UNSAFE macro in harfbuzz.
30#[inline]
31pub fn rb_flag64_unsafe(x: u32) -> u64 {
32    if x < 64 {
33        1 << (x as u64)
34    } else {
35        0
36    }
37}
38
39/* Encodes three unsigned integers in one 64-bit number.  If the inputs have more than 21 bits,
40 * values will be truncated / overlap, and might not decode exactly. */
41#[allow(non_snake_case, dead_code)]
42pub const fn HB_CODEPOINT_ENCODE3(x: u32, y: u32, z: u32) -> u64 {
43    ((x as u64) << 42) | ((y as u64) << 21) | (z as u64)
44}
45#[allow(non_snake_case, dead_code)]
46pub const fn HB_CODEPOINT_DECODE3_1(v: u64) -> u32 {
47    (v >> 42) as u32
48}
49#[allow(non_snake_case, dead_code)]
50pub const fn HB_CODEPOINT_DECODE3_2(v: u64) -> u32 {
51    ((v >> 21) & 0x001F_FFFF) as u32
52}
53#[allow(non_snake_case, dead_code)]
54pub const fn HB_CODEPOINT_DECODE3_3(v: u64) -> u32 {
55    (v & 0x001F_FFFF) as u32
56}
57
58/* Custom encoding used by hb-ucd. */
59#[allow(non_snake_case, dead_code)]
60pub const fn HB_CODEPOINT_ENCODE3_11_7_14(x: u32, y: u32, z: u32) -> u32 {
61    ((x & 0x07FF) << 21) | ((y & 0x007F) << 14) | (z & 0x3FFF)
62}
63#[allow(non_snake_case, dead_code)]
64pub const fn HB_CODEPOINT_DECODE3_11_7_14_1(v: u32) -> u32 {
65    v >> 21
66}
67#[allow(non_snake_case, dead_code)]
68pub const fn HB_CODEPOINT_DECODE3_11_7_14_2(v: u32) -> u32 {
69    ((v >> 14) & 0x007F) | 0x0300
70}
71#[allow(non_snake_case, dead_code)]
72pub const fn HB_CODEPOINT_DECODE3_11_7_14_3(v: u32) -> u32 {
73    v & 0x3FFF
74}