kludgine_core/text/
font.rs

1use std::fmt::Debug;
2use std::sync::atomic::{AtomicU64, Ordering};
3use std::sync::Arc;
4
5use easygpu::prelude::*;
6use figures::Figure;
7use lazy_static::lazy_static;
8use rusttype::{gpu_cache, Scale};
9use ttf_parser::name_id;
10
11use crate::math::Pixels;
12
13lazy_static! {
14    static ref GLOBAL_ID_CELL: AtomicU64 = AtomicU64::new(0);
15}
16
17/// Embeds a font into your executable.
18#[macro_export]
19macro_rules! include_font {
20    ($path:expr) => {{
21        let bytes = std::include_bytes!($path);
22        Font::try_from_bytes(bytes as &[u8]).expect("Error loading bundled font")
23    }};
24}
25
26/// Font provides TrueType Font rendering
27#[derive(Clone, Debug)]
28pub struct Font {
29    pub(crate) handle: Arc<FontData>,
30}
31
32impl Font {
33    /// Try to load a font from `bytes`.
34    #[must_use]
35    pub fn try_from_bytes(bytes: &'static [u8]) -> Option<Self> {
36        let font = rusttype::Font::try_from_bytes(bytes)?;
37        let id = GLOBAL_ID_CELL.fetch_add(1, Ordering::SeqCst);
38        Some(Self {
39            handle: Arc::new(FontData { id, font }),
40        })
41    }
42
43    /// Returns the unique ID of the font. This ID depends on load order, and is
44    /// not from the font data.
45    #[must_use]
46    pub fn id(&self) -> u64 {
47        self.handle.id
48    }
49
50    /// Measures the vertical metrics for a given size.
51    #[must_use]
52    pub fn metrics(&self, size: Figure<f32, Pixels>) -> rusttype::VMetrics {
53        self.handle
54            .font
55            .v_metrics(rusttype::Scale::uniform(size.get()))
56    }
57
58    /// Returns the name of the font's family, if available.
59    #[must_use]
60    pub fn family(&self) -> Option<String> {
61        match &self.handle.font {
62            rusttype::Font::Ref(f) => f
63                .names()
64                .get(name_id::FAMILY)
65                .and_then(|name| name.to_string()),
66            rusttype::Font::Owned(_) => None,
67        }
68    }
69
70    #[must_use]
71    pub(crate) fn glyph(&self, c: char) -> rusttype::Glyph<'static> {
72        self.handle.font.glyph(c)
73    }
74
75    #[must_use]
76    pub(crate) fn pair_kerning(
77        &self,
78        size: f32,
79        a: rusttype::GlyphId,
80        b: rusttype::GlyphId,
81    ) -> f32 {
82        self.handle.font.pair_kerning(Scale::uniform(size), a, b)
83    }
84}
85
86#[derive(Debug)]
87pub struct FontData {
88    pub(crate) id: u64,
89    pub(crate) font: rusttype::Font<'static>,
90}
91
92pub struct LoadedFont {
93    pub font: Font,
94    pub cache: gpu_cache::Cache<'static>,
95    pub(crate) binding: Option<BindingGroup>,
96    pub(crate) texture: Option<Texture>,
97}
98
99impl Debug for LoadedFont {
100    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
101        f.debug_struct("LoadedFont")
102            .field("font", &self.font)
103            .field("binding", &self.binding)
104            .field("texture", &self.texture)
105            .finish()
106    }
107}
108
109impl LoadedFont {
110    pub fn new(font: &Font) -> Self {
111        Self {
112            font: font.clone(),
113            cache: gpu_cache::Cache::builder().dimensions(512, 512).build(),
114            binding: None,
115            texture: None,
116        }
117    }
118}
kludgine_core/text/font.rs

kludgine_core/text/
font.rs
