1use crate::{
2 color::Color,
3 fonts::{FontId, GlyphId, Underline},
4 geometry::{
5 rect::RectF,
6 vector::{vec2f, Vector2F},
7 },
8 platform,
9 platform::FontSystem,
10 scene,
11 window::WindowContext,
12 SceneBuilder,
13};
14use ordered_float::OrderedFloat;
15use parking_lot::{Mutex, RwLock, RwLockUpgradableReadGuard};
16use smallvec::SmallVec;
17use std::{
18 borrow::Borrow,
19 collections::HashMap,
20 hash::{Hash, Hasher},
21 iter,
22 sync::Arc,
23};
24
25pub struct TextLayoutCache {
26 prev_frame: Mutex<HashMap<CacheKeyValue, Arc<LineLayout>>>,
27 curr_frame: RwLock<HashMap<CacheKeyValue, Arc<LineLayout>>>,
28 fonts: Arc<dyn platform::FontSystem>,
29}
30
31#[derive(Copy, Clone, Debug, PartialEq, Eq)]
32pub struct RunStyle {
33 pub color: Color,
34 pub font_id: FontId,
35 pub underline: Underline,
36}
37
38impl TextLayoutCache {
39 pub fn new(fonts: Arc<dyn platform::FontSystem>) -> Self {
40 Self {
41 prev_frame: Mutex::new(HashMap::new()),
42 curr_frame: RwLock::new(HashMap::new()),
43 fonts,
44 }
45 }
46
47 pub fn finish_frame(&self) {
48 let mut prev_frame = self.prev_frame.lock();
49 let mut curr_frame = self.curr_frame.write();
50 std::mem::swap(&mut *prev_frame, &mut *curr_frame);
51 curr_frame.clear();
52 }
53
54 pub fn layout_str<'a>(
55 &'a self,
56 text: &'a str,
57 font_size: f32,
58 runs: &'a [(usize, RunStyle)],
59 ) -> Line {
60 let key = &CacheKeyRef {
61 text,
62 font_size: OrderedFloat(font_size),
63 runs,
64 } as &dyn CacheKey;
65 let curr_frame = self.curr_frame.upgradable_read();
66 if let Some(layout) = curr_frame.get(key) {
67 return Line::new(layout.clone(), runs);
68 }
69
70 let mut curr_frame = RwLockUpgradableReadGuard::upgrade(curr_frame);
71 if let Some((key, layout)) = self.prev_frame.lock().remove_entry(key) {
72 curr_frame.insert(key, layout.clone());
73 Line::new(layout, runs)
74 } else {
75 let layout = Arc::new(self.fonts.layout_line(text, font_size, runs));
76 let key = CacheKeyValue {
77 text: text.into(),
78 font_size: OrderedFloat(font_size),
79 runs: SmallVec::from(runs),
80 };
81 curr_frame.insert(key, layout.clone());
82 Line::new(layout, runs)
83 }
84 }
85}
86
87trait CacheKey {
88 fn key(&self) -> CacheKeyRef;
89}
90
91impl<'a> PartialEq for (dyn CacheKey + 'a) {
92 fn eq(&self, other: &dyn CacheKey) -> bool {
93 self.key() == other.key()
94 }
95}
96
97impl<'a> Eq for (dyn CacheKey + 'a) {}
98
99impl<'a> Hash for (dyn CacheKey + 'a) {
100 fn hash<H: Hasher>(&self, state: &mut H) {
101 self.key().hash(state)
102 }
103}
104
105#[derive(Eq)]
106struct CacheKeyValue {
107 text: String,
108 font_size: OrderedFloat<f32>,
109 runs: SmallVec<[(usize, RunStyle); 1]>,
110}
111
112impl CacheKey for CacheKeyValue {
113 fn key(&self) -> CacheKeyRef {
114 CacheKeyRef {
115 text: self.text.as_str(),
116 font_size: self.font_size,
117 runs: self.runs.as_slice(),
118 }
119 }
120}
121
122impl PartialEq for CacheKeyValue {
123 fn eq(&self, other: &Self) -> bool {
124 self.key().eq(&other.key())
125 }
126}
127
128impl Hash for CacheKeyValue {
129 fn hash<H: Hasher>(&self, state: &mut H) {
130 self.key().hash(state);
131 }
132}
133
134impl<'a> Borrow<dyn CacheKey + 'a> for CacheKeyValue {
135 fn borrow(&self) -> &(dyn CacheKey + 'a) {
136 self as &dyn CacheKey
137 }
138}
139
140#[derive(Copy, Clone)]
141struct CacheKeyRef<'a> {
142 text: &'a str,
143 font_size: OrderedFloat<f32>,
144 runs: &'a [(usize, RunStyle)],
145}
146
147impl<'a> CacheKey for CacheKeyRef<'a> {
148 fn key(&self) -> CacheKeyRef {
149 *self
150 }
151}
152
153impl<'a> PartialEq for CacheKeyRef<'a> {
154 fn eq(&self, other: &Self) -> bool {
155 self.text == other.text
156 && self.font_size == other.font_size
157 && self.runs.len() == other.runs.len()
158 && self.runs.iter().zip(other.runs.iter()).all(
159 |((len_a, style_a), (len_b, style_b))| {
160 len_a == len_b && style_a.font_id == style_b.font_id
161 },
162 )
163 }
164}
165
166impl<'a> Hash for CacheKeyRef<'a> {
167 fn hash<H: Hasher>(&self, state: &mut H) {
168 self.text.hash(state);
169 self.font_size.hash(state);
170 for (len, style_id) in self.runs {
171 len.hash(state);
172 style_id.font_id.hash(state);
173 }
174 }
175}
176
177#[derive(Default, Debug, Clone)]
178pub struct Line {
179 layout: Arc<LineLayout>,
180 style_runs: SmallVec<[StyleRun; 32]>,
181}
182
183#[derive(Debug, Clone, Copy)]
184struct StyleRun {
185 len: u32,
186 color: Color,
187 underline: Underline,
188}
189
190#[derive(Default, Debug)]
191pub struct LineLayout {
192 pub width: f32,
193 pub ascent: f32,
194 pub descent: f32,
195 pub runs: Vec<Run>,
196 pub len: usize,
197 pub font_size: f32,
198}
199
200#[derive(Debug)]
201pub struct Run {
202 pub font_id: FontId,
203 pub glyphs: Vec<Glyph>,
204}
205
206#[derive(Clone, Debug)]
207pub struct Glyph {
208 pub id: GlyphId,
209 pub position: Vector2F,
210 pub index: usize,
211 pub is_emoji: bool,
212}
213
214#[derive(Debug, Clone)]
215pub enum Invisible {
216 Tab { line_start_offset: usize },
217 Whitespace { line_offset: usize },
218}
219
220impl Line {
221 fn new(layout: Arc<LineLayout>, runs: &[(usize, RunStyle)]) -> Self {
222 let mut style_runs = SmallVec::new();
223 for (len, style) in runs {
224 style_runs.push(StyleRun {
225 len: *len as u32,
226 color: style.color,
227 underline: style.underline,
228 });
229 }
230 Self { layout, style_runs }
231 }
232
233 pub fn runs(&self) -> &[Run] {
234 &self.layout.runs
235 }
236
237 pub fn width(&self) -> f32 {
238 self.layout.width
239 }
240
241 pub fn font_size(&self) -> f32 {
242 self.layout.font_size
243 }
244
245 pub fn x_for_index(&self, index: usize) -> f32 {
246 for run in &self.layout.runs {
247 for glyph in &run.glyphs {
248 if glyph.index >= index {
249 return glyph.position.x();
250 }
251 }
252 }
253 self.layout.width
254 }
255
256 pub fn font_for_index(&self, index: usize) -> Option<FontId> {
257 for run in &self.layout.runs {
258 for glyph in &run.glyphs {
259 if glyph.index >= index {
260 return Some(run.font_id);
261 }
262 }
263 }
264
265 None
266 }
267
268 pub fn len(&self) -> usize {
269 self.layout.len
270 }
271
272 pub fn is_empty(&self) -> bool {
273 self.layout.len == 0
274 }
275
276 pub fn index_for_x(&self, x: f32) -> Option<usize> {
277 if x >= self.layout.width {
278 None
279 } else {
280 for run in self.layout.runs.iter().rev() {
281 for glyph in run.glyphs.iter().rev() {
282 if glyph.position.x() <= x {
283 return Some(glyph.index);
284 }
285 }
286 }
287 Some(0)
288 }
289 }
290
291 pub fn paint(
292 &self,
293 scene: &mut SceneBuilder,
294 origin: Vector2F,
295 visible_bounds: RectF,
296 line_height: f32,
297 cx: &mut WindowContext,
298 ) {
299 let padding_top = (line_height - self.layout.ascent - self.layout.descent) / 2.;
300 let baseline_offset = vec2f(0., padding_top + self.layout.ascent);
301
302 let mut style_runs = self.style_runs.iter();
303 let mut run_end = 0;
304 let mut color = Color::black();
305 let mut underline = None;
306
307 for run in &self.layout.runs {
308 let max_glyph_width = cx
309 .font_cache
310 .bounding_box(run.font_id, self.layout.font_size)
311 .x();
312
313 for glyph in &run.glyphs {
314 let glyph_origin = origin + baseline_offset + glyph.position;
315 if glyph_origin.x() > visible_bounds.upper_right().x() {
316 break;
317 }
318
319 let mut finished_underline = None;
320 if glyph.index >= run_end {
321 if let Some(style_run) = style_runs.next() {
322 if let Some((_, underline_style)) = underline {
323 if style_run.underline != underline_style {
324 finished_underline = underline.take();
325 }
326 }
327 if style_run.underline.thickness.into_inner() > 0. {
328 underline.get_or_insert((
329 vec2f(
330 glyph_origin.x(),
331 origin.y() + baseline_offset.y() + 0.618 * self.layout.descent,
332 ),
333 Underline {
334 color: Some(
335 style_run.underline.color.unwrap_or(style_run.color),
336 ),
337 thickness: style_run.underline.thickness,
338 squiggly: style_run.underline.squiggly,
339 },
340 ));
341 }
342
343 run_end += style_run.len as usize;
344 color = style_run.color;
345 } else {
346 run_end = self.layout.len;
347 finished_underline = underline.take();
348 }
349 }
350
351 if glyph_origin.x() + max_glyph_width < visible_bounds.origin().x() {
352 continue;
353 }
354
355 if let Some((underline_origin, underline_style)) = finished_underline {
356 scene.push_underline(scene::Underline {
357 origin: underline_origin,
358 width: glyph_origin.x() - underline_origin.x(),
359 thickness: underline_style.thickness.into(),
360 color: underline_style.color.unwrap(),
361 squiggly: underline_style.squiggly,
362 });
363 }
364
365 if glyph.is_emoji {
366 scene.push_image_glyph(scene::ImageGlyph {
367 font_id: run.font_id,
368 font_size: self.layout.font_size,
369 id: glyph.id,
370 origin: glyph_origin,
371 });
372 } else {
373 scene.push_glyph(scene::Glyph {
374 font_id: run.font_id,
375 font_size: self.layout.font_size,
376 id: glyph.id,
377 origin: glyph_origin,
378 color,
379 });
380 }
381 }
382 }
383
384 if let Some((underline_start, underline_style)) = underline.take() {
385 let line_end_x = origin.x() + self.layout.width;
386 scene.push_underline(scene::Underline {
387 origin: underline_start,
388 width: line_end_x - underline_start.x(),
389 color: underline_style.color.unwrap(),
390 thickness: underline_style.thickness.into(),
391 squiggly: underline_style.squiggly,
392 });
393 }
394 }
395
396 pub fn paint_wrapped(
397 &self,
398 scene: &mut SceneBuilder,
399 origin: Vector2F,
400 visible_bounds: RectF,
401 line_height: f32,
402 boundaries: &[ShapedBoundary],
403 cx: &mut WindowContext,
404 ) {
405 let padding_top = (line_height - self.layout.ascent - self.layout.descent) / 2.;
406 let baseline_offset = vec2f(0., padding_top + self.layout.ascent);
407
408 let mut boundaries = boundaries.into_iter().peekable();
409 let mut color_runs = self.style_runs.iter();
410 let mut style_run_end = 0;
411 let mut color = Color::black();
412 let mut underline: Option<(Vector2F, Underline)> = None;
413
414 let mut glyph_origin = origin;
415 let mut prev_position = 0.;
416 for (run_ix, run) in self.layout.runs.iter().enumerate() {
417 for (glyph_ix, glyph) in run.glyphs.iter().enumerate() {
418 glyph_origin.set_x(glyph_origin.x() + glyph.position.x() - prev_position);
419
420 if boundaries
421 .peek()
422 .map_or(false, |b| b.run_ix == run_ix && b.glyph_ix == glyph_ix)
423 {
424 boundaries.next();
425 if let Some((underline_origin, underline_style)) = underline {
426 scene.push_underline(scene::Underline {
427 origin: underline_origin,
428 width: glyph_origin.x() - underline_origin.x(),
429 thickness: underline_style.thickness.into(),
430 color: underline_style.color.unwrap(),
431 squiggly: underline_style.squiggly,
432 });
433 }
434
435 glyph_origin = vec2f(origin.x(), glyph_origin.y() + line_height);
436 }
437 prev_position = glyph.position.x();
438
439 let mut finished_underline = None;
440 if glyph.index >= style_run_end {
441 if let Some(style_run) = color_runs.next() {
442 style_run_end += style_run.len as usize;
443 color = style_run.color;
444 if let Some((_, underline_style)) = underline {
445 if style_run.underline != underline_style {
446 finished_underline = underline.take();
447 }
448 }
449 if style_run.underline.thickness.into_inner() > 0. {
450 underline.get_or_insert((
451 glyph_origin
452 + vec2f(0., baseline_offset.y() + 0.618 * self.layout.descent),
453 Underline {
454 color: Some(
455 style_run.underline.color.unwrap_or(style_run.color),
456 ),
457 thickness: style_run.underline.thickness,
458 squiggly: style_run.underline.squiggly,
459 },
460 ));
461 }
462 } else {
463 style_run_end = self.layout.len;
464 color = Color::black();
465 finished_underline = underline.take();
466 }
467 }
468
469 if let Some((underline_origin, underline_style)) = finished_underline {
470 scene.push_underline(scene::Underline {
471 origin: underline_origin,
472 width: glyph_origin.x() - underline_origin.x(),
473 thickness: underline_style.thickness.into(),
474 color: underline_style.color.unwrap(),
475 squiggly: underline_style.squiggly,
476 });
477 }
478
479 let glyph_bounds = RectF::new(
480 glyph_origin,
481 cx.font_cache
482 .bounding_box(run.font_id, self.layout.font_size),
483 );
484 if glyph_bounds.intersects(visible_bounds) {
485 if glyph.is_emoji {
486 scene.push_image_glyph(scene::ImageGlyph {
487 font_id: run.font_id,
488 font_size: self.layout.font_size,
489 id: glyph.id,
490 origin: glyph_bounds.origin() + baseline_offset,
491 });
492 } else {
493 scene.push_glyph(scene::Glyph {
494 font_id: run.font_id,
495 font_size: self.layout.font_size,
496 id: glyph.id,
497 origin: glyph_bounds.origin() + baseline_offset,
498 color,
499 });
500 }
501 }
502 }
503 }
504
505 if let Some((underline_origin, underline_style)) = underline.take() {
506 let line_end_x = glyph_origin.x() + self.layout.width - prev_position;
507 scene.push_underline(scene::Underline {
508 origin: underline_origin,
509 width: line_end_x - underline_origin.x(),
510 thickness: underline_style.thickness.into(),
511 color: underline_style.color.unwrap(),
512 squiggly: underline_style.squiggly,
513 });
514 }
515 }
516}
517
518impl Run {
519 pub fn glyphs(&self) -> &[Glyph] {
520 &self.glyphs
521 }
522}
523
524#[derive(Copy, Clone, Debug, PartialEq, Eq)]
525pub struct Boundary {
526 pub ix: usize,
527 pub next_indent: u32,
528}
529
530#[derive(Clone, Copy, Debug, PartialEq, Eq, PartialOrd, Ord)]
531pub struct ShapedBoundary {
532 pub run_ix: usize,
533 pub glyph_ix: usize,
534}
535
536impl Boundary {
537 fn new(ix: usize, next_indent: u32) -> Self {
538 Self { ix, next_indent }
539 }
540}
541
542pub struct LineWrapper {
543 font_system: Arc<dyn FontSystem>,
544 pub(crate) font_id: FontId,
545 pub(crate) font_size: f32,
546 cached_ascii_char_widths: [f32; 128],
547 cached_other_char_widths: HashMap<char, f32>,
548}
549
550impl LineWrapper {
551 pub const MAX_INDENT: u32 = 256;
552
553 pub fn new(font_id: FontId, font_size: f32, font_system: Arc<dyn FontSystem>) -> Self {
554 Self {
555 font_system,
556 font_id,
557 font_size,
558 cached_ascii_char_widths: [f32::NAN; 128],
559 cached_other_char_widths: HashMap::new(),
560 }
561 }
562
563 pub fn wrap_line<'a>(
564 &'a mut self,
565 line: &'a str,
566 wrap_width: f32,
567 ) -> impl Iterator<Item = Boundary> + 'a {
568 let mut width = 0.0;
569 let mut first_non_whitespace_ix = None;
570 let mut indent = None;
571 let mut last_candidate_ix = 0;
572 let mut last_candidate_width = 0.0;
573 let mut last_wrap_ix = 0;
574 let mut prev_c = '\0';
575 let mut char_indices = line.char_indices();
576 iter::from_fn(move || {
577 for (ix, c) in char_indices.by_ref() {
578 if c == '\n' {
579 continue;
580 }
581
582 if self.is_boundary(prev_c, c) && first_non_whitespace_ix.is_some() {
583 last_candidate_ix = ix;
584 last_candidate_width = width;
585 }
586
587 if c != ' ' && first_non_whitespace_ix.is_none() {
588 first_non_whitespace_ix = Some(ix);
589 }
590
591 let char_width = self.width_for_char(c);
592 width += char_width;
593 if width > wrap_width && ix > last_wrap_ix {
594 if let (None, Some(first_non_whitespace_ix)) = (indent, first_non_whitespace_ix)
595 {
596 indent = Some(
597 Self::MAX_INDENT.min((first_non_whitespace_ix - last_wrap_ix) as u32),
598 );
599 }
600
601 if last_candidate_ix > 0 {
602 last_wrap_ix = last_candidate_ix;
603 width -= last_candidate_width;
604 last_candidate_ix = 0;
605 } else {
606 last_wrap_ix = ix;
607 width = char_width;
608 }
609
610 let indent_width =
611 indent.map(|indent| indent as f32 * self.width_for_char(' '));
612 width += indent_width.unwrap_or(0.);
613
614 return Some(Boundary::new(last_wrap_ix, indent.unwrap_or(0)));
615 }
616 prev_c = c;
617 }
618
619 None
620 })
621 }
622
623 pub fn wrap_shaped_line<'a>(
624 &'a mut self,
625 str: &'a str,
626 line: &'a Line,
627 wrap_width: f32,
628 ) -> impl Iterator<Item = ShapedBoundary> + 'a {
629 let mut first_non_whitespace_ix = None;
630 let mut last_candidate_ix = None;
631 let mut last_candidate_x = 0.0;
632 let mut last_wrap_ix = ShapedBoundary {
633 run_ix: 0,
634 glyph_ix: 0,
635 };
636 let mut last_wrap_x = 0.;
637 let mut prev_c = '\0';
638 let mut glyphs = line
639 .runs()
640 .iter()
641 .enumerate()
642 .flat_map(move |(run_ix, run)| {
643 run.glyphs()
644 .iter()
645 .enumerate()
646 .map(move |(glyph_ix, glyph)| {
647 let character = str[glyph.index..].chars().next().unwrap();
648 (
649 ShapedBoundary { run_ix, glyph_ix },
650 character,
651 glyph.position.x(),
652 )
653 })
654 })
655 .peekable();
656
657 iter::from_fn(move || {
658 while let Some((ix, c, x)) = glyphs.next() {
659 if c == '\n' {
660 continue;
661 }
662
663 if self.is_boundary(prev_c, c) && first_non_whitespace_ix.is_some() {
664 last_candidate_ix = Some(ix);
665 last_candidate_x = x;
666 }
667
668 if c != ' ' && first_non_whitespace_ix.is_none() {
669 first_non_whitespace_ix = Some(ix);
670 }
671
672 let next_x = glyphs.peek().map_or(line.width(), |(_, _, x)| *x);
673 let width = next_x - last_wrap_x;
674 if width > wrap_width && ix > last_wrap_ix {
675 if let Some(last_candidate_ix) = last_candidate_ix.take() {
676 last_wrap_ix = last_candidate_ix;
677 last_wrap_x = last_candidate_x;
678 } else {
679 last_wrap_ix = ix;
680 last_wrap_x = x;
681 }
682
683 return Some(last_wrap_ix);
684 }
685 prev_c = c;
686 }
687
688 None
689 })
690 }
691
692 fn is_boundary(&self, prev: char, next: char) -> bool {
693 (prev == ' ') && (next != ' ')
694 }
695
696 #[inline(always)]
697 fn width_for_char(&mut self, c: char) -> f32 {
698 if (c as u32) < 128 {
699 let mut width = self.cached_ascii_char_widths[c as usize];
700 if width.is_nan() {
701 width = self.compute_width_for_char(c);
702 self.cached_ascii_char_widths[c as usize] = width;
703 }
704 width
705 } else {
706 let mut width = self
707 .cached_other_char_widths
708 .get(&c)
709 .copied()
710 .unwrap_or(f32::NAN);
711 if width.is_nan() {
712 width = self.compute_width_for_char(c);
713 self.cached_other_char_widths.insert(c, width);
714 }
715 width
716 }
717 }
718
719 fn compute_width_for_char(&self, c: char) -> f32 {
720 self.font_system
721 .layout_line(
722 &c.to_string(),
723 self.font_size,
724 &[(
725 1,
726 RunStyle {
727 font_id: self.font_id,
728 color: Default::default(),
729 underline: Default::default(),
730 },
731 )],
732 )
733 .width
734 }
735}
736
737#[cfg(test)]
738mod tests {
739 use super::*;
740 use crate::fonts::{Properties, Weight};
741
742 #[crate::test(self)]
743 fn test_wrap_line(cx: &mut crate::AppContext) {
744 let font_cache = cx.font_cache().clone();
745 let font_system = cx.platform().fonts();
746 let family = font_cache
747 .load_family(&["Courier"], &Default::default())
748 .unwrap();
749 let font_id = font_cache.select_font(family, &Default::default()).unwrap();
750
751 let mut wrapper = LineWrapper::new(font_id, 16., font_system);
752 assert_eq!(
753 wrapper
754 .wrap_line("aa bbb cccc ddddd eeee", 72.0)
755 .collect::<Vec<_>>(),
756 &[
757 Boundary::new(7, 0),
758 Boundary::new(12, 0),
759 Boundary::new(18, 0)
760 ],
761 );
762 assert_eq!(
763 wrapper
764 .wrap_line("aaa aaaaaaaaaaaaaaaaaa", 72.0)
765 .collect::<Vec<_>>(),
766 &[
767 Boundary::new(4, 0),
768 Boundary::new(11, 0),
769 Boundary::new(18, 0)
770 ],
771 );
772 assert_eq!(
773 wrapper.wrap_line(" aaaaaaa", 72.).collect::<Vec<_>>(),
774 &[
775 Boundary::new(7, 5),
776 Boundary::new(9, 5),
777 Boundary::new(11, 5),
778 ]
779 );
780 assert_eq!(
781 wrapper
782 .wrap_line(" ", 72.)
783 .collect::<Vec<_>>(),
784 &[
785 Boundary::new(7, 0),
786 Boundary::new(14, 0),
787 Boundary::new(21, 0)
788 ]
789 );
790 assert_eq!(
791 wrapper
792 .wrap_line(" aaaaaaaaaaaaaa", 72.)
793 .collect::<Vec<_>>(),
794 &[
795 Boundary::new(7, 0),
796 Boundary::new(14, 3),
797 Boundary::new(18, 3),
798 Boundary::new(22, 3),
799 ]
800 );
801 }
802
803 #[crate::test(self, retries = 5)]
804 fn test_wrap_shaped_line(cx: &mut crate::AppContext) {
805 // This is failing intermittently on CI and we don't have time to figure it out
806 let font_cache = cx.font_cache().clone();
807 let font_system = cx.platform().fonts();
808 let text_layout_cache = TextLayoutCache::new(font_system.clone());
809
810 let family = font_cache
811 .load_family(&["Helvetica"], &Default::default())
812 .unwrap();
813 let font_id = font_cache.select_font(family, &Default::default()).unwrap();
814 let normal = RunStyle {
815 font_id,
816 color: Default::default(),
817 underline: Default::default(),
818 };
819 let bold = RunStyle {
820 font_id: font_cache
821 .select_font(
822 family,
823 &Properties {
824 weight: Weight::BOLD,
825 ..Default::default()
826 },
827 )
828 .unwrap(),
829 color: Default::default(),
830 underline: Default::default(),
831 };
832
833 let text = "aa bbb cccc ddddd eeee";
834 let line = text_layout_cache.layout_str(
835 text,
836 16.0,
837 &[(4, normal), (5, bold), (6, normal), (1, bold), (7, normal)],
838 );
839
840 let mut wrapper = LineWrapper::new(font_id, 16., font_system);
841 assert_eq!(
842 wrapper
843 .wrap_shaped_line(text, &line, 72.0)
844 .collect::<Vec<_>>(),
845 &[
846 ShapedBoundary {
847 run_ix: 1,
848 glyph_ix: 3
849 },
850 ShapedBoundary {
851 run_ix: 2,
852 glyph_ix: 3
853 },
854 ShapedBoundary {
855 run_ix: 4,
856 glyph_ix: 2
857 }
858 ],
859 );
860 }
861}