1// Copyright © SixtyFPS GmbH <info@slint.dev>
2// SPDX-License-Identifier: GPL-3.0-only OR LicenseRef-Slint-Royalty-free-2.0 OR LicenseRef-Slint-Software-3.0
3
4use crate::slice::Slice;
5
6#[repr(C)]
7#[derive(Debug)]
8/// A pre-rendered glyph with the alpha map and associated metrics
9pub struct BitmapGlyph {
10 /// The starting x-coordinate for the glyph, relative to the base line
11 /// This is a fixed point number that is shifted by 6 bits
12 pub x: i16,
13 /// The starting y-coordinate for the glyph, relative to the base line
14 /// This is a fixed point number that is shifted by 6 bits
15 pub y: i16,
16 /// The width of the glyph in pixels
17 pub width: i16,
18 /// The height of the glyph in pixels
19 pub height: i16,
20 /// The horizontal distance to the next glyph
21 /// This is a fixed point number that is shifted by 6 bits
22 pub x_advance: i16,
23 /// The 8-bit alpha map that's to be blended with the current text color
24 /// or 8-bit signed distance field depending on `BitmapFont::sdf`
25 pub data: Slice<'static, u8>,
26}
27
28#[repr(C)]
29#[derive(Debug)]
30/// A set of pre-rendered bitmap glyphs at a fixed pixel size
31pub struct BitmapGlyphs {
32 /// The font size in pixels at which the glyphs were pre-rendered. The boundaries of glyphs may exceed this
33 /// size, if the font designer has chosen so. This is only used for matching.
34 pub pixel_size: i16,
35 /// The data of the pre-rendered glyphs
36 pub glyph_data: Slice<'static, BitmapGlyph>,
37}
38
39#[repr(C)]
40#[derive(Debug)]
41/// An entry in the character map of a [`BitmapFont`].
42pub struct CharacterMapEntry {
43 /// The unicode code point for a given glyph
44 pub code_point: char,
45 /// The corresponding index in the `glyph_data` of [`BitmapGlyphs`]
46 pub glyph_index: u16,
47}
48
49#[repr(C)]
50#[derive(Debug)]
51/// A subset of an originally scalable font that's rendered ahead of time.
52pub struct BitmapFont {
53 /// The family name of the font
54 pub family_name: Slice<'static, u8>,
55 /// A vector of code points and their corresponding glyph index, sorted by code point.
56 pub character_map: Slice<'static, CharacterMapEntry>,
57 /// The font supplied size of the em square.
58 pub units_per_em: f32,
59 /// The font ascent in design metrics (typically positive)
60 pub ascent: f32,
61 /// The font descent in design metrics (typically negative)
62 pub descent: f32,
63 /// The font's x-height.
64 pub x_height: f32,
65 /// The font's cap-height.
66 pub cap_height: f32,
67 /// A vector of pre-rendered glyph sets. Each glyph set must have the same number of glyphs,
68 /// which must be at least as big as the largest glyph index in the character map.
69 pub glyphs: Slice<'static, BitmapGlyphs>,
70 /// The weight of the font in CSS units (400 is normal).
71 pub weight: u16,
72 /// Whether the type-face is rendered italic.
73 pub italic: bool,
74 /// Whether the format of the font is a signed distance field
75 pub sdf: bool,
76}
77