iced_graphics/
text.rs

1//! Draw text.
2pub mod cache;
3pub mod editor;
4pub mod paragraph;
5
6pub use cache::Cache;
7pub use editor::Editor;
8pub use paragraph::Paragraph;
9
10pub use cosmic_text;
11
12use crate::core::alignment;
13use crate::core::font::{self, Font};
14use crate::core::text::{Alignment, Ellipsis, Shaping, Wrapping};
15use crate::core::{Color, Pixels, Point, Rectangle, Size, Transformation};
16
17use std::borrow::Cow;
18use std::collections::HashSet;
19use std::sync::{Arc, OnceLock, RwLock, Weak};
20
21/// A text primitive.
22#[derive(Debug, Clone, PartialEq)]
23pub enum Text {
24    /// A paragraph.
25    #[allow(missing_docs)]
26    Paragraph {
27        paragraph: paragraph::Weak,
28        position: Point,
29        color: Color,
30        clip_bounds: Rectangle,
31        transformation: Transformation,
32    },
33    /// An editor.
34    #[allow(missing_docs)]
35    Editor {
36        editor: editor::Weak,
37        position: Point,
38        color: Color,
39        clip_bounds: Rectangle,
40        transformation: Transformation,
41    },
42    /// Some cached text.
43    Cached {
44        /// The contents of the text.
45        content: String,
46        /// The bounds of the text.
47        bounds: Rectangle,
48        /// The color of the text.
49        color: Color,
50        /// The size of the text in logical pixels.
51        size: Pixels,
52        /// The line height of the text.
53        line_height: Pixels,
54        /// The font of the text.
55        font: Font,
56        /// The horizontal alignment of the text.
57        align_x: Alignment,
58        /// The vertical alignment of the text.
59        align_y: alignment::Vertical,
60        /// The shaping strategy of the text.
61        shaping: Shaping,
62        /// The wrapping strategy of the text.
63        wrapping: Wrapping,
64        /// The ellipsis strategy of the text.
65        ellipsis: Ellipsis,
66        /// The clip bounds of the text.
67        clip_bounds: Rectangle,
68    },
69    /// Some raw text.
70    #[allow(missing_docs)]
71    Raw {
72        raw: Raw,
73        transformation: Transformation,
74    },
75}
76
77impl Text {
78    /// Returns the visible bounds of the [`Text`].
79    pub fn visible_bounds(&self) -> Option<Rectangle> {
80        match self {
81            Text::Paragraph {
82                position,
83                paragraph,
84                clip_bounds,
85                transformation,
86                ..
87            } => Rectangle::new(*position, paragraph.min_bounds)
88                .intersection(clip_bounds)
89                .map(|bounds| bounds * *transformation),
90            Text::Editor {
91                editor,
92                position,
93                clip_bounds,
94                transformation,
95                ..
96            } => Rectangle::new(*position, editor.bounds)
97                .intersection(clip_bounds)
98                .map(|bounds| bounds * *transformation),
99            Text::Cached {
100                bounds,
101                clip_bounds,
102                ..
103            } => bounds.intersection(clip_bounds),
104            Text::Raw { raw, .. } => Some(raw.clip_bounds),
105        }
106    }
107}
108
109/// The regular variant of the [Fira Sans] font.
110///
111/// It is loaded as part of the default fonts when the `fira-sans`
112/// feature is enabled.
113///
114/// [Fira Sans]: https://mozilla.github.io/Fira/
115#[cfg(feature = "fira-sans")]
116pub const FIRA_SANS_REGULAR: &[u8] = include_bytes!("../fonts/FiraSans-Regular.ttf").as_slice();
117
118/// Returns the global [`FontSystem`].
119pub fn font_system() -> &'static RwLock<FontSystem> {
120    static FONT_SYSTEM: OnceLock<RwLock<FontSystem>> = OnceLock::new();
121
122    FONT_SYSTEM.get_or_init(|| {
123        #[allow(unused_mut)]
124        let mut raw = cosmic_text::FontSystem::new_with_fonts([
125            cosmic_text::fontdb::Source::Binary(Arc::new(
126                include_bytes!("../fonts/Iced-Icons.ttf").as_slice(),
127            )),
128            #[cfg(feature = "fira-sans")]
129            cosmic_text::fontdb::Source::Binary(Arc::new(
130                include_bytes!("../fonts/FiraSans-Regular.ttf").as_slice(),
131            )),
132        ]);
133
134        #[cfg(feature = "fira-sans")]
135        raw.db_mut().set_sans_serif_family("Fira Sans");
136
137        #[cfg(target_os = "macos")]
138        {
139            #[cfg(not(feature = "fira-sans"))]
140            raw.db_mut().set_sans_serif_family(".SF NS");
141            raw.db_mut().set_serif_family("Times New Roman");
142            raw.db_mut().set_monospace_family("Menlo");
143        }
144
145        #[cfg(target_os = "windows")]
146        {
147            #[cfg(not(feature = "fira-sans"))]
148            raw.db_mut().set_sans_serif_family("Segoe UI");
149            raw.db_mut().set_serif_family("Times New Roman");
150            raw.db_mut().set_monospace_family("Consolas");
151        }
152
153        RwLock::new(FontSystem {
154            raw,
155            loaded_fonts: HashSet::new(),
156            version: Version::default(),
157        })
158    })
159}
160
161/// A set of system fonts.
162pub struct FontSystem {
163    raw: cosmic_text::FontSystem,
164    loaded_fonts: HashSet<usize>,
165    version: Version,
166}
167
168impl FontSystem {
169    /// Returns the raw [`cosmic_text::FontSystem`].
170    pub fn raw(&mut self) -> &mut cosmic_text::FontSystem {
171        &mut self.raw
172    }
173
174    /// Loads a font from its bytes.
175    pub fn load_font(&mut self, bytes: Cow<'static, [u8]>) {
176        if let Cow::Borrowed(bytes) = bytes {
177            let address = bytes.as_ptr() as usize;
178
179            if !self.loaded_fonts.insert(address) {
180                return;
181            }
182        }
183
184        let _ = self
185            .raw
186            .db_mut()
187            .load_font_source(cosmic_text::fontdb::Source::Binary(Arc::new(
188                bytes.into_owned(),
189            )));
190
191        self.version = Version(self.version.0 + 1);
192    }
193
194    /// Returns an iterator over the family names of all font faces
195    /// in the font database.
196    pub fn families(&self) -> impl Iterator<Item = &str> {
197        self.raw
198            .db()
199            .faces()
200            .filter_map(|face| face.families.first())
201            .map(|(name, _)| name.as_str())
202    }
203
204    /// Returns the current [`Version`] of the [`FontSystem`].
205    ///
206    /// Loading a font will increase the version of a [`FontSystem`].
207    pub fn version(&self) -> Version {
208        self.version
209    }
210}
211
212/// A version number.
213#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash, Default)]
214pub struct Version(u32);
215
216/// A weak reference to a [`cosmic_text::Buffer`] that can be drawn.
217#[derive(Debug, Clone)]
218pub struct Raw {
219    /// A weak reference to a [`cosmic_text::Buffer`].
220    pub buffer: Weak<cosmic_text::Buffer>,
221    /// The position of the text.
222    pub position: Point,
223    /// The color of the text.
224    pub color: Color,
225    /// The clip bounds of the text.
226    pub clip_bounds: Rectangle,
227}
228
229impl PartialEq for Raw {
230    fn eq(&self, _other: &Self) -> bool {
231        // TODO: There is no proper way to compare raw buffers
232        // For now, no two instances of `Raw` text will be equal.
233        // This should be fine, but could trigger unnecessary redraws
234        // in the future.
235        false
236    }
237}
238
239/// Measures the dimensions of the given [`cosmic_text::Buffer`].
240pub fn measure(buffer: &cosmic_text::Buffer) -> (Size, bool) {
241    let (width, height, has_rtl) =
242        buffer
243            .layout_runs()
244            .fold((0.0, 0.0, false), |(width, height, has_rtl), run| {
245                (
246                    run.line_w.max(width),
247                    height + run.line_height,
248                    has_rtl || run.rtl,
249                )
250            });
251
252    (Size::new(width, height), has_rtl)
253}
254
255/// Aligns the given [`cosmic_text::Buffer`] with the given [`Alignment`]
256/// and returns its minimum [`Size`].
257pub fn align(
258    buffer: &mut cosmic_text::Buffer,
259    font_system: &mut cosmic_text::FontSystem,
260    alignment: Alignment,
261) -> Size {
262    let (min_bounds, has_rtl) = measure(buffer);
263    let mut needs_relayout = has_rtl;
264
265    if let Some(align) = to_align(alignment) {
266        let has_multiple_lines = buffer.lines.len() > 1
267            || buffer
268                .lines
269                .first()
270                .is_some_and(|line| line.layout_opt().is_some_and(|layout| layout.len() > 1));
271
272        if has_multiple_lines {
273            for line in &mut buffer.lines {
274                let _ = line.set_align(Some(align));
275            }
276
277            needs_relayout = true;
278        } else if let Some(line) = buffer.lines.first_mut() {
279            needs_relayout |= line.set_align(None);
280        }
281    }
282
283    // TODO: Avoid relayout with some changes to `cosmic-text` (?)
284    if needs_relayout {
285        log::trace!("Relayouting paragraph...");
286
287        buffer.set_size(Some(min_bounds.width), Some(min_bounds.height));
288        buffer.shape_until_scroll(font_system, false);
289    }
290
291    min_bounds
292}
293
294/// Returns the attributes of the given [`Font`].
295pub fn to_attributes(font: Font) -> cosmic_text::Attrs<'static> {
296    cosmic_text::Attrs::new()
297        .family(to_family(font.family))
298        .weight(to_weight(font.weight))
299        .stretch(to_stretch(font.stretch))
300        .style(to_style(font.style))
301}
302
303fn to_family(family: font::Family) -> cosmic_text::Family<'static> {
304    match family {
305        font::Family::Name(name) => cosmic_text::Family::Name(name),
306        font::Family::SansSerif => cosmic_text::Family::SansSerif,
307        font::Family::Serif => cosmic_text::Family::Serif,
308        font::Family::Cursive => cosmic_text::Family::Cursive,
309        font::Family::Fantasy => cosmic_text::Family::Fantasy,
310        font::Family::Monospace => cosmic_text::Family::Monospace,
311    }
312}
313
314fn to_weight(weight: font::Weight) -> cosmic_text::Weight {
315    match weight {
316        font::Weight::Thin => cosmic_text::Weight::THIN,
317        font::Weight::ExtraLight => cosmic_text::Weight::EXTRA_LIGHT,
318        font::Weight::Light => cosmic_text::Weight::LIGHT,
319        font::Weight::Normal => cosmic_text::Weight::NORMAL,
320        font::Weight::Medium => cosmic_text::Weight::MEDIUM,
321        font::Weight::Semibold => cosmic_text::Weight::SEMIBOLD,
322        font::Weight::Bold => cosmic_text::Weight::BOLD,
323        font::Weight::ExtraBold => cosmic_text::Weight::EXTRA_BOLD,
324        font::Weight::Black => cosmic_text::Weight::BLACK,
325    }
326}
327
328fn to_stretch(stretch: font::Stretch) -> cosmic_text::Stretch {
329    match stretch {
330        font::Stretch::UltraCondensed => cosmic_text::Stretch::UltraCondensed,
331        font::Stretch::ExtraCondensed => cosmic_text::Stretch::ExtraCondensed,
332        font::Stretch::Condensed => cosmic_text::Stretch::Condensed,
333        font::Stretch::SemiCondensed => cosmic_text::Stretch::SemiCondensed,
334        font::Stretch::Normal => cosmic_text::Stretch::Normal,
335        font::Stretch::SemiExpanded => cosmic_text::Stretch::SemiExpanded,
336        font::Stretch::Expanded => cosmic_text::Stretch::Expanded,
337        font::Stretch::ExtraExpanded => cosmic_text::Stretch::ExtraExpanded,
338        font::Stretch::UltraExpanded => cosmic_text::Stretch::UltraExpanded,
339    }
340}
341
342fn to_style(style: font::Style) -> cosmic_text::Style {
343    match style {
344        font::Style::Normal => cosmic_text::Style::Normal,
345        font::Style::Italic => cosmic_text::Style::Italic,
346        font::Style::Oblique => cosmic_text::Style::Oblique,
347    }
348}
349
350fn to_align(alignment: Alignment) -> Option<cosmic_text::Align> {
351    match alignment {
352        Alignment::Default => None,
353        Alignment::Left => Some(cosmic_text::Align::Left),
354        Alignment::Center => Some(cosmic_text::Align::Center),
355        Alignment::Right => Some(cosmic_text::Align::Right),
356        Alignment::Justified => Some(cosmic_text::Align::Justified),
357    }
358}
359
360/// Converts some [`Shaping`] strategy to a [`cosmic_text::Shaping`] strategy.
361pub fn to_shaping(shaping: Shaping, text: &str) -> cosmic_text::Shaping {
362    match shaping {
363        Shaping::Auto => {
364            if text.is_ascii() {
365                cosmic_text::Shaping::Basic
366            } else {
367                cosmic_text::Shaping::Advanced
368            }
369        }
370        Shaping::Basic => cosmic_text::Shaping::Basic,
371        Shaping::Advanced => cosmic_text::Shaping::Advanced,
372    }
373}
374
375/// Converts some [`Wrapping`] strategy to a [`cosmic_text::Wrap`] strategy.
376pub fn to_wrap(wrapping: Wrapping) -> cosmic_text::Wrap {
377    match wrapping {
378        Wrapping::None => cosmic_text::Wrap::None,
379        Wrapping::Word => cosmic_text::Wrap::Word,
380        Wrapping::Glyph => cosmic_text::Wrap::Glyph,
381        Wrapping::WordOrGlyph => cosmic_text::Wrap::WordOrGlyph,
382    }
383}
384
385/// Converts some [`Ellipsis`] strategy to a [`cosmic_text::Ellipsize`] strategy.
386pub fn to_ellipsize(ellipsis: Ellipsis, max_height: f32) -> cosmic_text::Ellipsize {
387    let limit = cosmic_text::EllipsizeHeightLimit::Height(max_height);
388
389    match ellipsis {
390        Ellipsis::None => cosmic_text::Ellipsize::None,
391        Ellipsis::Start => cosmic_text::Ellipsize::Start(limit),
392        Ellipsis::Middle => cosmic_text::Ellipsize::Middle(limit),
393        Ellipsis::End => cosmic_text::Ellipsize::End(limit),
394    }
395}
396
397/// Converts some [`Color`] to a [`cosmic_text::Color`].
398pub fn to_color(color: Color) -> cosmic_text::Color {
399    let [r, g, b, a] = color.into_rgba8();
400
401    cosmic_text::Color::rgba(r, g, b, a)
402}
403
404/// Returns the ideal hint factor given the size and scale factor of some text.
405pub fn hint_factor(_size: Pixels, _scale_factor: Option<f32>) -> Option<f32> {
406    // TODO: Fix hinting in `cosmic-text`
407    // const MAX_HINTING_SIZE: f32 = 18.0;
408
409    // let hint_factor = scale_factor?;
410
411    // if size.0 * hint_factor < MAX_HINTING_SIZE {
412    //     Some(hint_factor)
413    // } else {
414    //     None
415    // }
416
417    None // Disable all text hinting for now
418}
419
420/// A text renderer coupled to `iced_graphics`.
421pub trait Renderer {
422    /// Draws the given [`Raw`] text.
423    fn fill_raw(&mut self, raw: Raw);
424}
iced_graphics/text.rs

iced_graphics/
text.rs
