1#[cfg(not(feature = "std"))]
4use alloc::{string::String, vec::Vec};
5
6use core::{cmp, fmt};
7
8#[cfg(not(feature = "std"))]
9use core_maths::CoreFloat;
10use unicode_segmentation::UnicodeSegmentation;
11
12#[cfg(feature = "swash")]
13use crate::Color;
14
15use crate::{
16 Affinity, Align, Attrs, AttrsList, BidiParagraphs, BorrowedWithFontSystem, BufferLine, Cursor,
17 FontSystem, LayoutCursor, LayoutGlyph, LayoutLine, LineEnding, LineIter, Motion, Scroll,
18 ShapeLine, Shaping, Wrap,
19};
20
21#[derive(Debug)]
23pub struct LayoutRun<'a> {
24 pub line_i: usize,
26 pub text: &'a str,
28 pub rtl: bool,
30 pub glyphs: &'a [LayoutGlyph],
32 pub line_y: f32,
34 pub line_top: f32,
36 pub line_height: f32,
38 pub line_w: f32,
40}
41
42impl LayoutRun<'_> {
43 #[allow(clippy::missing_panics_doc)]
48 pub fn highlight(&self, cursor_start: Cursor, cursor_end: Cursor) -> Option<(f32, f32)> {
49 let mut x_start = None;
50 let mut x_end = None;
51 let rtl_factor = if self.rtl { 1. } else { 0. };
52 let ltr_factor = 1. - rtl_factor;
53 for glyph in self.glyphs {
54 let cursor = self.cursor_from_glyph_left(glyph);
55 if cursor >= cursor_start && cursor <= cursor_end {
56 if x_start.is_none() {
57 x_start = Some(glyph.x + glyph.w.mul_add(rtl_factor, 0.0));
58 }
59 x_end = Some(glyph.x + glyph.w.mul_add(rtl_factor, 0.0));
60 }
61 let cursor = self.cursor_from_glyph_right(glyph);
62 if cursor >= cursor_start && cursor <= cursor_end {
63 if x_start.is_none() {
64 x_start = Some(glyph.x + glyph.w.mul_add(ltr_factor, 0.0));
65 }
66 x_end = Some(glyph.x + glyph.w.mul_add(ltr_factor, 0.0));
67 }
68 }
69 x_start.map(|x_start| {
70 let x_end = x_end.expect("end of cursor not found");
71 let (x_start, x_end) = if x_start < x_end {
72 (x_start, x_end)
73 } else {
74 (x_end, x_start)
75 };
76 (x_start, x_end - x_start)
77 })
78 }
79
80 const fn cursor_from_glyph_left(&self, glyph: &LayoutGlyph) -> Cursor {
81 if self.rtl {
82 Cursor::new_with_affinity(self.line_i, glyph.end, Affinity::Before)
83 } else {
84 Cursor::new_with_affinity(self.line_i, glyph.start, Affinity::After)
85 }
86 }
87
88 const fn cursor_from_glyph_right(&self, glyph: &LayoutGlyph) -> Cursor {
89 if self.rtl {
90 Cursor::new_with_affinity(self.line_i, glyph.start, Affinity::After)
91 } else {
92 Cursor::new_with_affinity(self.line_i, glyph.end, Affinity::Before)
93 }
94 }
95}
96
97#[derive(Debug)]
99pub struct LayoutRunIter<'b> {
100 buffer: &'b Buffer,
101 line_i: usize,
102 layout_i: usize,
103 total_height: f32,
104 line_top: f32,
105}
106
107impl<'b> LayoutRunIter<'b> {
108 pub const fn new(buffer: &'b Buffer) -> Self {
109 Self {
110 buffer,
111 line_i: buffer.scroll.line,
112 layout_i: 0,
113 total_height: 0.0,
114 line_top: 0.0,
115 }
116 }
117}
118
119impl<'b> Iterator for LayoutRunIter<'b> {
120 type Item = LayoutRun<'b>;
121
122 fn next(&mut self) -> Option<Self::Item> {
123 while let Some(line) = self.buffer.lines.get(self.line_i) {
124 let shape = line.shape_opt()?;
125 let layout = line.layout_opt()?;
126 while let Some(layout_line) = layout.get(self.layout_i) {
127 self.layout_i += 1;
128
129 let line_height = layout_line
130 .line_height_opt
131 .unwrap_or(self.buffer.metrics.line_height);
132 self.total_height += line_height;
133
134 let line_top = self.line_top - self.buffer.scroll.vertical;
135 let glyph_height = layout_line.max_ascent + layout_line.max_descent;
136 let centering_offset = (line_height - glyph_height) / 2.0;
137 let line_y = line_top + centering_offset + layout_line.max_ascent;
138 if let Some(height) = self.buffer.height_opt {
139 if line_y - layout_line.max_ascent > height {
140 return None;
141 }
142 }
143 self.line_top += line_height;
144 if line_y + layout_line.max_descent < 0.0 {
145 continue;
146 }
147
148 return Some(LayoutRun {
149 line_i: self.line_i,
150 text: line.text(),
151 rtl: shape.rtl,
152 glyphs: &layout_line.glyphs,
153 line_y,
154 line_top,
155 line_height,
156 line_w: layout_line.w,
157 });
158 }
159 self.line_i += 1;
160 self.layout_i = 0;
161 }
162
163 None
164 }
165}
166
167#[derive(Clone, Copy, Debug, Default, PartialEq)]
169pub struct Metrics {
170 pub font_size: f32,
172 pub line_height: f32,
174}
175
176impl Metrics {
177 pub const fn new(font_size: f32, line_height: f32) -> Self {
179 Self {
180 font_size,
181 line_height,
182 }
183 }
184
185 pub fn relative(font_size: f32, line_height_scale: f32) -> Self {
187 Self {
188 font_size,
189 line_height: font_size * line_height_scale,
190 }
191 }
192
193 pub fn scale(self, scale: f32) -> Self {
195 Self {
196 font_size: self.font_size * scale,
197 line_height: self.line_height * scale,
198 }
199 }
200}
201
202impl fmt::Display for Metrics {
203 fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
204 write!(f, "{}px / {}px", self.font_size, self.line_height)
205 }
206}
207
208#[derive(Debug)]
210pub struct Buffer {
211 pub lines: Vec<BufferLine>,
213 metrics: Metrics,
214 width_opt: Option<f32>,
215 height_opt: Option<f32>,
216 scroll: Scroll,
217 redraw: bool,
219 wrap: Wrap,
220 monospace_width: Option<f32>,
221 tab_width: u16,
222}
223
224impl Clone for Buffer {
225 fn clone(&self) -> Self {
226 Self {
227 lines: self.lines.clone(),
228 metrics: self.metrics,
229 width_opt: self.width_opt,
230 height_opt: self.height_opt,
231 scroll: self.scroll,
232 redraw: self.redraw,
233 wrap: self.wrap,
234 monospace_width: self.monospace_width,
235 tab_width: self.tab_width,
236 }
237 }
238}
239
240impl Buffer {
241 pub fn new_empty(metrics: Metrics) -> Self {
253 assert_ne!(metrics.line_height, 0.0, "line height cannot be 0");
254 Self {
255 lines: Vec::new(),
256 metrics,
257 width_opt: None,
258 height_opt: None,
259 scroll: Scroll::default(),
260 redraw: false,
261 wrap: Wrap::WordOrGlyph,
262 monospace_width: None,
263 tab_width: 8,
264 }
265 }
266
267 pub fn new(font_system: &mut FontSystem, metrics: Metrics) -> Self {
273 let mut buffer = Self::new_empty(metrics);
274 buffer.set_text(font_system, "", &Attrs::new(), Shaping::Advanced, None);
275 buffer
276 }
277
278 pub fn borrow_with<'a>(
280 &'a mut self,
281 font_system: &'a mut FontSystem,
282 ) -> BorrowedWithFontSystem<'a, Self> {
283 BorrowedWithFontSystem {
284 inner: self,
285 font_system,
286 }
287 }
288
289 fn relayout(&mut self, font_system: &mut FontSystem) {
290 #[cfg(all(feature = "std", not(target_arch = "wasm32")))]
291 let instant = std::time::Instant::now();
292
293 for line in &mut self.lines {
294 if line.shape_opt().is_some() {
295 line.reset_layout();
296 line.layout(
297 font_system,
298 self.metrics.font_size,
299 self.width_opt,
300 self.wrap,
301 self.monospace_width,
302 self.tab_width,
303 );
304 }
305 }
306
307 self.redraw = true;
308
309 #[cfg(all(feature = "std", not(target_arch = "wasm32")))]
310 log::debug!("relayout: {:?}", instant.elapsed());
311 }
312
313 #[allow(clippy::missing_panics_doc)]
315 pub fn shape_until_cursor(
316 &mut self,
317 font_system: &mut FontSystem,
318 cursor: Cursor,
319 prune: bool,
320 ) {
321 let metrics = self.metrics;
322 let old_scroll = self.scroll;
323
324 let layout_cursor = self
325 .layout_cursor(font_system, cursor)
326 .expect("shape_until_cursor invalid cursor");
327
328 let mut layout_y = 0.0;
329 let mut total_height = {
330 let layout = self
331 .line_layout(font_system, layout_cursor.line)
332 .expect("shape_until_cursor failed to scroll forwards");
333 (0..layout_cursor.layout).for_each(|layout_i| {
334 layout_y += layout[layout_i]
335 .line_height_opt
336 .unwrap_or(metrics.line_height);
337 });
338 layout_y
339 + layout[layout_cursor.layout]
340 .line_height_opt
341 .unwrap_or(metrics.line_height)
342 };
343
344 if self.scroll.line > layout_cursor.line
345 || (self.scroll.line == layout_cursor.line && self.scroll.vertical > layout_y)
346 {
347 self.scroll.line = layout_cursor.line;
349 self.scroll.vertical = layout_y;
350 } else if let Some(height) = self.height_opt {
351 let mut line_i = layout_cursor.line;
353 if line_i <= self.scroll.line {
354 if total_height > height + self.scroll.vertical {
356 self.scroll.vertical = total_height - height;
357 }
358 } else {
359 while line_i > self.scroll.line {
360 line_i -= 1;
361 let layout = self
362 .line_layout(font_system, line_i)
363 .expect("shape_until_cursor failed to scroll forwards");
364 for layout_line in layout {
365 total_height += layout_line.line_height_opt.unwrap_or(metrics.line_height);
366 }
367 if total_height > height + self.scroll.vertical {
368 self.scroll.line = line_i;
369 self.scroll.vertical = total_height - height;
370 }
371 }
372 }
373 }
374
375 if old_scroll != self.scroll {
376 self.redraw = true;
377 }
378
379 self.shape_until_scroll(font_system, prune);
380
381 if let Some(layout_cursor) = self.layout_cursor(font_system, cursor) {
383 if let Some(layout_lines) = self.line_layout(font_system, layout_cursor.line) {
384 if let Some(layout_line) = layout_lines.get(layout_cursor.layout) {
385 let (x_min, x_max) = layout_line
386 .glyphs
387 .get(layout_cursor.glyph)
388 .or_else(|| layout_line.glyphs.last())
389 .map_or((0.0, 0.0), |glyph| {
390 let x_a = glyph.x;
392 let x_b = glyph.x + glyph.w;
393 (x_a.min(x_b), x_a.max(x_b))
394 });
395 if x_min < self.scroll.horizontal {
396 self.scroll.horizontal = x_min;
397 self.redraw = true;
398 }
399 if let Some(width) = self.width_opt {
400 if x_max > self.scroll.horizontal + width {
401 self.scroll.horizontal = x_max - width;
402 self.redraw = true;
403 }
404 }
405 }
406 }
407 }
408 }
409
410 #[allow(clippy::missing_panics_doc)]
412 pub fn shape_until_scroll(&mut self, font_system: &mut FontSystem, prune: bool) {
413 let metrics = self.metrics;
414 let old_scroll = self.scroll;
415
416 loop {
417 while self.scroll.vertical < 0.0 {
419 if self.scroll.line > 0 {
420 let line_i = self.scroll.line - 1;
421 if let Some(layout) = self.line_layout(font_system, line_i) {
422 let mut layout_height = 0.0;
423 for layout_line in layout {
424 layout_height +=
425 layout_line.line_height_opt.unwrap_or(metrics.line_height);
426 }
427 self.scroll.line = line_i;
428 self.scroll.vertical += layout_height;
429 } else {
430 self.scroll.line = line_i;
432 self.scroll.vertical += metrics.line_height;
433 }
434 } else {
435 self.scroll.vertical = 0.0;
436 break;
437 }
438 }
439
440 let scroll_start = self.scroll.vertical;
441 let scroll_end = scroll_start + self.height_opt.unwrap_or(f32::INFINITY);
442
443 let mut total_height = 0.0;
444 for line_i in 0..self.lines.len() {
445 if line_i < self.scroll.line {
446 if prune {
447 self.lines[line_i].reset_shaping();
448 }
449 continue;
450 }
451 if total_height > scroll_end {
452 if prune {
453 self.lines[line_i].reset_shaping();
454 continue;
455 }
456 break;
457 }
458
459 let mut layout_height = 0.0;
460 let layout = self
461 .line_layout(font_system, line_i)
462 .expect("shape_until_scroll invalid line");
463 for layout_line in layout {
464 let line_height = layout_line.line_height_opt.unwrap_or(metrics.line_height);
465 layout_height += line_height;
466 total_height += line_height;
467 }
468
469 if line_i == self.scroll.line && layout_height <= self.scroll.vertical {
471 self.scroll.line += 1;
472 self.scroll.vertical -= layout_height;
473 }
474 }
475
476 if total_height < scroll_end && self.scroll.line > 0 {
477 self.scroll.vertical -= scroll_end - total_height;
479 } else {
480 break;
482 }
483 }
484
485 if old_scroll != self.scroll {
486 self.redraw = true;
487 }
488 }
489
490 pub fn layout_cursor(
492 &mut self,
493 font_system: &mut FontSystem,
494 cursor: Cursor,
495 ) -> Option<LayoutCursor> {
496 let layout = self.line_layout(font_system, cursor.line)?;
497 for (layout_i, layout_line) in layout.iter().enumerate() {
498 for (glyph_i, glyph) in layout_line.glyphs.iter().enumerate() {
499 let cursor_end =
500 Cursor::new_with_affinity(cursor.line, glyph.end, Affinity::Before);
501 let cursor_start =
502 Cursor::new_with_affinity(cursor.line, glyph.start, Affinity::After);
503 let (cursor_left, cursor_right) = if glyph.level.is_ltr() {
504 (cursor_start, cursor_end)
505 } else {
506 (cursor_end, cursor_start)
507 };
508 if cursor == cursor_left {
509 return Some(LayoutCursor::new(cursor.line, layout_i, glyph_i));
510 }
511 if cursor == cursor_right {
512 return Some(LayoutCursor::new(cursor.line, layout_i, glyph_i + 1));
513 }
514 }
515 }
516
517 Some(LayoutCursor::new(cursor.line, 0, 0))
520 }
521
522 pub fn line_shape(
524 &mut self,
525 font_system: &mut FontSystem,
526 line_i: usize,
527 ) -> Option<&ShapeLine> {
528 let line = self.lines.get_mut(line_i)?;
529 Some(line.shape(font_system, self.tab_width))
530 }
531
532 pub fn line_layout(
534 &mut self,
535 font_system: &mut FontSystem,
536 line_i: usize,
537 ) -> Option<&[LayoutLine]> {
538 let line = self.lines.get_mut(line_i)?;
539 Some(line.layout(
540 font_system,
541 self.metrics.font_size,
542 self.width_opt,
543 self.wrap,
544 self.monospace_width,
545 self.tab_width,
546 ))
547 }
548
549 pub const fn metrics(&self) -> Metrics {
551 self.metrics
552 }
553
554 pub fn set_metrics(&mut self, font_system: &mut FontSystem, metrics: Metrics) {
560 self.set_metrics_and_size(font_system, metrics, self.width_opt, self.height_opt);
561 }
562
563 pub const fn wrap(&self) -> Wrap {
565 self.wrap
566 }
567
568 pub fn set_wrap(&mut self, font_system: &mut FontSystem, wrap: Wrap) {
570 if wrap != self.wrap {
571 self.wrap = wrap;
572 self.relayout(font_system);
573 self.shape_until_scroll(font_system, false);
574 }
575 }
576
577 pub const fn monospace_width(&self) -> Option<f32> {
579 self.monospace_width
580 }
581
582 pub fn set_monospace_width(
584 &mut self,
585 font_system: &mut FontSystem,
586 monospace_width: Option<f32>,
587 ) {
588 if monospace_width != self.monospace_width {
589 self.monospace_width = monospace_width;
590 self.relayout(font_system);
591 self.shape_until_scroll(font_system, false);
592 }
593 }
594
595 pub const fn tab_width(&self) -> u16 {
597 self.tab_width
598 }
599
600 pub fn set_tab_width(&mut self, font_system: &mut FontSystem, tab_width: u16) {
602 if tab_width == 0 {
604 return;
605 }
606 if tab_width != self.tab_width {
607 self.tab_width = tab_width;
608 for line in &mut self.lines {
610 if line.shape_opt().is_some() && line.text().contains('\t') {
611 line.reset_shaping();
612 }
613 }
614 self.redraw = true;
615 self.shape_until_scroll(font_system, false);
616 }
617 }
618
619 pub const fn size(&self) -> (Option<f32>, Option<f32>) {
621 (self.width_opt, self.height_opt)
622 }
623
624 pub fn set_size(
626 &mut self,
627 font_system: &mut FontSystem,
628 width_opt: Option<f32>,
629 height_opt: Option<f32>,
630 ) {
631 self.set_metrics_and_size(font_system, self.metrics, width_opt, height_opt);
632 }
633
634 pub fn set_metrics_and_size(
640 &mut self,
641 font_system: &mut FontSystem,
642 metrics: Metrics,
643 width_opt: Option<f32>,
644 height_opt: Option<f32>,
645 ) {
646 let clamped_width_opt = width_opt.map(|width| width.max(0.0));
647 let clamped_height_opt = height_opt.map(|height| height.max(0.0));
648
649 if metrics != self.metrics
650 || clamped_width_opt != self.width_opt
651 || clamped_height_opt != self.height_opt
652 {
653 assert_ne!(metrics.font_size, 0.0, "font size cannot be 0");
654 self.metrics = metrics;
655 self.width_opt = clamped_width_opt;
656 self.height_opt = clamped_height_opt;
657 self.relayout(font_system);
658 self.shape_until_scroll(font_system, false);
659 }
660 }
661
662 pub const fn scroll(&self) -> Scroll {
664 self.scroll
665 }
666
667 pub fn set_scroll(&mut self, scroll: Scroll) {
669 if scroll != self.scroll {
670 self.scroll = scroll;
671 self.redraw = true;
672 }
673 }
674
675 pub fn set_text(
677 &mut self,
678 font_system: &mut FontSystem,
679 text: &str,
680 attrs: &Attrs,
681 shaping: Shaping,
682 alignment: Option<Align>,
683 ) {
684 self.lines.clear();
685 for (range, ending) in LineIter::new(text) {
686 self.lines.push(BufferLine::new(
687 &text[range],
688 ending,
689 AttrsList::new(attrs),
690 shaping,
691 ));
692 }
693 if self.lines.is_empty() {
694 self.lines.push(BufferLine::new(
695 "",
696 LineEnding::default(),
697 AttrsList::new(attrs),
698 shaping,
699 ));
700 }
701
702 if alignment.is_some() {
703 self.lines.iter_mut().for_each(|line| {
704 line.set_align(alignment);
705 });
706 }
707
708 self.scroll = Scroll::default();
709 self.shape_until_scroll(font_system, false);
710 }
711
712 pub fn set_rich_text<'r, 's, I>(
731 &mut self,
732 font_system: &mut FontSystem,
733 spans: I,
734 default_attrs: &Attrs,
735 shaping: Shaping,
736 alignment: Option<Align>,
737 ) where
738 I: IntoIterator<Item = (&'s str, Attrs<'r>)>,
739 {
740 let mut end = 0;
741 let (string, spans_data): (String, Vec<_>) = spans
743 .into_iter()
744 .map(|(s, attrs)| {
745 let start = end;
746 end += s.len();
747 (s, (attrs, start..end))
748 })
749 .unzip();
750
751 let mut spans_iter = spans_data.into_iter();
752 let mut maybe_span = spans_iter.next();
753
754 let string_start = string.as_ptr() as usize;
756 let mut lines_iter = BidiParagraphs::new(&string).map(|line: &str| {
757 let start = line.as_ptr() as usize - string_start;
758 let end = start + line.len();
759 start..end
760 });
761 let mut maybe_line = lines_iter.next();
762 let line_ending = LineEnding::default();
764
765 let mut line_count = 0;
766 let mut attrs_list = self
767 .lines
768 .get_mut(line_count)
769 .map_or_else(|| AttrsList::new(&Attrs::new()), BufferLine::reclaim_attrs)
770 .reset(default_attrs);
771 let mut line_string = self
772 .lines
773 .get_mut(line_count)
774 .map(BufferLine::reclaim_text)
775 .unwrap_or_default();
776
777 loop {
778 let (Some(line_range), Some((attrs, span_range))) = (&maybe_line, &maybe_span) else {
779 if self.lines.len() == line_count {
781 self.lines.push(BufferLine::empty());
782 }
783 self.lines[line_count].reset_new(
784 String::new(),
785 line_ending,
786 AttrsList::new(default_attrs),
787 shaping,
788 );
789 line_count += 1;
790 break;
791 };
792
793 let start = line_range.start.max(span_range.start);
795 let end = line_range.end.min(span_range.end);
796 if start < end {
797 let text = &string[start..end];
798 let text_start = line_string.len();
799 line_string.push_str(text);
800 let text_end = line_string.len();
801 if *attrs != attrs_list.defaults() {
803 attrs_list.add_span(text_start..text_end, attrs);
804 }
805 }
806
807 if span_range.end < line_range.end {
813 maybe_span = spans_iter.next();
814 } else {
815 maybe_line = lines_iter.next();
816 if maybe_line.is_some() {
817 let next_attrs_list = self
819 .lines
820 .get_mut(line_count + 1)
821 .map_or_else(|| AttrsList::new(&Attrs::new()), BufferLine::reclaim_attrs)
822 .reset(default_attrs);
823 let next_line_string = self
824 .lines
825 .get_mut(line_count + 1)
826 .map(BufferLine::reclaim_text)
827 .unwrap_or_default();
828 let prev_attrs_list = core::mem::replace(&mut attrs_list, next_attrs_list);
829 let prev_line_string = core::mem::replace(&mut line_string, next_line_string);
830 if self.lines.len() == line_count {
831 self.lines.push(BufferLine::empty());
832 }
833 self.lines[line_count].reset_new(
834 prev_line_string,
835 line_ending,
836 prev_attrs_list,
837 shaping,
838 );
839 line_count += 1;
840 } else {
841 if self.lines.len() == line_count {
843 self.lines.push(BufferLine::empty());
844 }
845 self.lines[line_count].reset_new(line_string, line_ending, attrs_list, shaping);
846 line_count += 1;
847 break;
848 }
849 }
850 }
851
852 self.lines.truncate(line_count);
854
855 self.lines.iter_mut().for_each(|line| {
856 line.set_align(alignment);
857 });
858
859 self.scroll = Scroll::default();
860
861 self.shape_until_scroll(font_system, false);
862 }
863
864 pub const fn redraw(&self) -> bool {
866 self.redraw
867 }
868
869 pub fn set_redraw(&mut self, redraw: bool) {
871 self.redraw = redraw;
872 }
873
874 pub fn layout_runs(&self) -> LayoutRunIter<'_> {
876 LayoutRunIter::new(self)
877 }
878
879 pub fn hit(&self, x: f32, y: f32) -> Option<Cursor> {
881 #[cfg(all(feature = "std", not(target_arch = "wasm32")))]
882 let instant = std::time::Instant::now();
883
884 let mut new_cursor_opt = None;
885
886 let mut runs = self.layout_runs().peekable();
887 let mut first_run = true;
888 while let Some(run) = runs.next() {
889 let line_top = run.line_top;
890 let line_height = run.line_height;
891
892 if first_run && y < line_top {
893 first_run = false;
894 let new_cursor = Cursor::new(run.line_i, 0);
895 new_cursor_opt = Some(new_cursor);
896 } else if y >= line_top && y < line_top + line_height {
897 let mut new_cursor_glyph = run.glyphs.len();
898 let mut new_cursor_char = 0;
899 let mut new_cursor_affinity = Affinity::After;
900
901 let mut first_glyph = true;
902
903 'hit: for (glyph_i, glyph) in run.glyphs.iter().enumerate() {
904 if first_glyph {
905 first_glyph = false;
906 if (run.rtl && x > glyph.x) || (!run.rtl && x < 0.0) {
907 new_cursor_glyph = 0;
908 new_cursor_char = 0;
909 }
910 }
911 if x >= glyph.x && x <= glyph.x + glyph.w {
912 new_cursor_glyph = glyph_i;
913
914 let cluster = &run.text[glyph.start..glyph.end];
915 let total = cluster.grapheme_indices(true).count();
916 let mut egc_x = glyph.x;
917 let egc_w = glyph.w / (total as f32);
918 for (egc_i, egc) in cluster.grapheme_indices(true) {
919 if x >= egc_x && x <= egc_x + egc_w {
920 new_cursor_char = egc_i;
921
922 let right_half = x >= egc_x + egc_w / 2.0;
923 if right_half != glyph.level.is_rtl() {
924 new_cursor_char += egc.len();
926 new_cursor_affinity = Affinity::Before;
927 }
928 break 'hit;
929 }
930 egc_x += egc_w;
931 }
932
933 let right_half = x >= glyph.x + glyph.w / 2.0;
934 if right_half != glyph.level.is_rtl() {
935 new_cursor_char = cluster.len();
937 new_cursor_affinity = Affinity::Before;
938 }
939 break 'hit;
940 }
941 }
942
943 let mut new_cursor = Cursor::new(run.line_i, 0);
944
945 match run.glyphs.get(new_cursor_glyph) {
946 Some(glyph) => {
947 new_cursor.index = glyph.start + new_cursor_char;
949 new_cursor.affinity = new_cursor_affinity;
950 }
951 None => {
952 if let Some(glyph) = run.glyphs.last() {
953 new_cursor.index = glyph.end;
955 new_cursor.affinity = Affinity::Before;
956 }
957 }
958 }
959
960 new_cursor_opt = Some(new_cursor);
961
962 break;
963 } else if runs.peek().is_none() && y > run.line_y {
964 let mut new_cursor = Cursor::new(run.line_i, 0);
965 if let Some(glyph) = run.glyphs.last() {
966 new_cursor = run.cursor_from_glyph_right(glyph);
967 }
968 new_cursor_opt = Some(new_cursor);
969 }
970 }
971
972 #[cfg(all(feature = "std", not(target_arch = "wasm32")))]
973 log::trace!("click({}, {}): {:?}", x, y, instant.elapsed());
974
975 new_cursor_opt
976 }
977
978 pub fn cursor_motion(
980 &mut self,
981 font_system: &mut FontSystem,
982 mut cursor: Cursor,
983 mut cursor_x_opt: Option<i32>,
984 motion: Motion,
985 ) -> Option<(Cursor, Option<i32>)> {
986 match motion {
987 Motion::LayoutCursor(layout_cursor) => {
988 let layout = self.line_layout(font_system, layout_cursor.line)?;
989
990 let layout_line = match layout.get(layout_cursor.layout) {
991 Some(some) => some,
992 None => match layout.last() {
993 Some(some) => some,
994 None => {
995 return None;
996 }
997 },
998 };
999
1000 let (new_index, new_affinity) =
1001 layout_line.glyphs.get(layout_cursor.glyph).map_or_else(
1002 || {
1003 layout_line
1004 .glyphs
1005 .last()
1006 .map_or((0, Affinity::After), |glyph| (glyph.end, Affinity::Before))
1007 },
1008 |glyph| (glyph.start, Affinity::After),
1009 );
1010
1011 if cursor.line != layout_cursor.line
1012 || cursor.index != new_index
1013 || cursor.affinity != new_affinity
1014 {
1015 cursor.line = layout_cursor.line;
1016 cursor.index = new_index;
1017 cursor.affinity = new_affinity;
1018 }
1019 }
1020 Motion::Previous => {
1021 let line = self.lines.get(cursor.line)?;
1022 if cursor.index > 0 {
1023 let mut prev_index = 0;
1025 for (i, _) in line.text().grapheme_indices(true) {
1026 if i < cursor.index {
1027 prev_index = i;
1028 } else {
1029 break;
1030 }
1031 }
1032
1033 cursor.index = prev_index;
1034 cursor.affinity = Affinity::After;
1035 } else if cursor.line > 0 {
1036 cursor.line -= 1;
1037 cursor.index = self.lines.get(cursor.line)?.text().len();
1038 cursor.affinity = Affinity::After;
1039 }
1040 cursor_x_opt = None;
1041 }
1042 Motion::Next => {
1043 let line = self.lines.get(cursor.line)?;
1044 if cursor.index < line.text().len() {
1045 for (i, c) in line.text().grapheme_indices(true) {
1046 if i == cursor.index {
1047 cursor.index += c.len();
1048 cursor.affinity = Affinity::Before;
1049 break;
1050 }
1051 }
1052 } else if cursor.line + 1 < self.lines.len() {
1053 cursor.line += 1;
1054 cursor.index = 0;
1055 cursor.affinity = Affinity::Before;
1056 }
1057 cursor_x_opt = None;
1058 }
1059 Motion::Left => {
1060 let rtl_opt = self
1061 .line_shape(font_system, cursor.line)
1062 .map(|shape| shape.rtl);
1063 if let Some(rtl) = rtl_opt {
1064 if rtl {
1065 (cursor, cursor_x_opt) =
1066 self.cursor_motion(font_system, cursor, cursor_x_opt, Motion::Next)?;
1067 } else {
1068 (cursor, cursor_x_opt) = self.cursor_motion(
1069 font_system,
1070 cursor,
1071 cursor_x_opt,
1072 Motion::Previous,
1073 )?;
1074 }
1075 }
1076 }
1077 Motion::Right => {
1078 let rtl_opt = self
1079 .line_shape(font_system, cursor.line)
1080 .map(|shape| shape.rtl);
1081 if let Some(rtl) = rtl_opt {
1082 if rtl {
1083 (cursor, cursor_x_opt) = self.cursor_motion(
1084 font_system,
1085 cursor,
1086 cursor_x_opt,
1087 Motion::Previous,
1088 )?;
1089 } else {
1090 (cursor, cursor_x_opt) =
1091 self.cursor_motion(font_system, cursor, cursor_x_opt, Motion::Next)?;
1092 }
1093 }
1094 }
1095 Motion::Up => {
1096 let mut layout_cursor = self.layout_cursor(font_system, cursor)?;
1097
1098 if cursor_x_opt.is_none() {
1099 cursor_x_opt = Some(
1100 layout_cursor.glyph as i32, );
1102 }
1103
1104 if layout_cursor.layout > 0 {
1105 layout_cursor.layout -= 1;
1106 } else if layout_cursor.line > 0 {
1107 layout_cursor.line -= 1;
1108 layout_cursor.layout = usize::MAX;
1109 }
1110
1111 if let Some(cursor_x) = cursor_x_opt {
1112 layout_cursor.glyph = cursor_x as usize; }
1114
1115 (cursor, cursor_x_opt) = self.cursor_motion(
1116 font_system,
1117 cursor,
1118 cursor_x_opt,
1119 Motion::LayoutCursor(layout_cursor),
1120 )?;
1121 }
1122 Motion::Down => {
1123 let mut layout_cursor = self.layout_cursor(font_system, cursor)?;
1124
1125 let layout_len = self.line_layout(font_system, layout_cursor.line)?.len();
1126
1127 if cursor_x_opt.is_none() {
1128 cursor_x_opt = Some(
1129 layout_cursor.glyph as i32, );
1131 }
1132
1133 if layout_cursor.layout + 1 < layout_len {
1134 layout_cursor.layout += 1;
1135 } else if layout_cursor.line + 1 < self.lines.len() {
1136 layout_cursor.line += 1;
1137 layout_cursor.layout = 0;
1138 }
1139
1140 if let Some(cursor_x) = cursor_x_opt {
1141 layout_cursor.glyph = cursor_x as usize; }
1143
1144 (cursor, cursor_x_opt) = self.cursor_motion(
1145 font_system,
1146 cursor,
1147 cursor_x_opt,
1148 Motion::LayoutCursor(layout_cursor),
1149 )?;
1150 }
1151 Motion::Home => {
1152 let mut layout_cursor = self.layout_cursor(font_system, cursor)?;
1153 layout_cursor.glyph = 0;
1154 #[allow(unused_assignments)]
1155 {
1156 (cursor, cursor_x_opt) = self.cursor_motion(
1157 font_system,
1158 cursor,
1159 cursor_x_opt,
1160 Motion::LayoutCursor(layout_cursor),
1161 )?;
1162 }
1163 cursor_x_opt = None;
1164 }
1165 Motion::SoftHome => {
1166 let line = self.lines.get(cursor.line)?;
1167 cursor.index = line
1168 .text()
1169 .char_indices()
1170 .find_map(|(i, c)| if c.is_whitespace() { None } else { Some(i) })
1171 .unwrap_or(0);
1172 cursor_x_opt = None;
1173 }
1174 Motion::End => {
1175 let mut layout_cursor = self.layout_cursor(font_system, cursor)?;
1176 layout_cursor.glyph = usize::MAX;
1177 #[allow(unused_assignments)]
1178 {
1179 (cursor, cursor_x_opt) = self.cursor_motion(
1180 font_system,
1181 cursor,
1182 cursor_x_opt,
1183 Motion::LayoutCursor(layout_cursor),
1184 )?;
1185 }
1186 cursor_x_opt = None;
1187 }
1188 Motion::ParagraphStart => {
1189 cursor.index = 0;
1190 cursor_x_opt = None;
1191 }
1192 Motion::ParagraphEnd => {
1193 cursor.index = self.lines.get(cursor.line)?.text().len();
1194 cursor_x_opt = None;
1195 }
1196 Motion::PageUp => {
1197 if let Some(height) = self.height_opt {
1198 (cursor, cursor_x_opt) = self.cursor_motion(
1199 font_system,
1200 cursor,
1201 cursor_x_opt,
1202 Motion::Vertical(-height as i32),
1203 )?;
1204 }
1205 }
1206 Motion::PageDown => {
1207 if let Some(height) = self.height_opt {
1208 (cursor, cursor_x_opt) = self.cursor_motion(
1209 font_system,
1210 cursor,
1211 cursor_x_opt,
1212 Motion::Vertical(height as i32),
1213 )?;
1214 }
1215 }
1216 Motion::Vertical(px) => {
1217 let lines = px / self.metrics().line_height as i32;
1219 match lines.cmp(&0) {
1220 cmp::Ordering::Less => {
1221 for _ in 0..-lines {
1222 (cursor, cursor_x_opt) =
1223 self.cursor_motion(font_system, cursor, cursor_x_opt, Motion::Up)?;
1224 }
1225 }
1226 cmp::Ordering::Greater => {
1227 for _ in 0..lines {
1228 (cursor, cursor_x_opt) = self.cursor_motion(
1229 font_system,
1230 cursor,
1231 cursor_x_opt,
1232 Motion::Down,
1233 )?;
1234 }
1235 }
1236 cmp::Ordering::Equal => {}
1237 }
1238 }
1239 Motion::PreviousWord => {
1240 let line = self.lines.get(cursor.line)?;
1241 if cursor.index > 0 {
1242 cursor.index = line
1243 .text()
1244 .unicode_word_indices()
1245 .rev()
1246 .map(|(i, _)| i)
1247 .find(|&i| i < cursor.index)
1248 .unwrap_or(0);
1249 } else if cursor.line > 0 {
1250 cursor.line -= 1;
1251 cursor.index = self.lines.get(cursor.line)?.text().len();
1252 }
1253 cursor_x_opt = None;
1254 }
1255 Motion::NextWord => {
1256 let line = self.lines.get(cursor.line)?;
1257 if cursor.index < line.text().len() {
1258 cursor.index = line
1259 .text()
1260 .unicode_word_indices()
1261 .map(|(i, word)| i + word.len())
1262 .find(|&i| i > cursor.index)
1263 .unwrap_or_else(|| line.text().len());
1264 } else if cursor.line + 1 < self.lines.len() {
1265 cursor.line += 1;
1266 cursor.index = 0;
1267 }
1268 cursor_x_opt = None;
1269 }
1270 Motion::LeftWord => {
1271 let rtl_opt = self
1272 .line_shape(font_system, cursor.line)
1273 .map(|shape| shape.rtl);
1274 if let Some(rtl) = rtl_opt {
1275 if rtl {
1276 (cursor, cursor_x_opt) = self.cursor_motion(
1277 font_system,
1278 cursor,
1279 cursor_x_opt,
1280 Motion::NextWord,
1281 )?;
1282 } else {
1283 (cursor, cursor_x_opt) = self.cursor_motion(
1284 font_system,
1285 cursor,
1286 cursor_x_opt,
1287 Motion::PreviousWord,
1288 )?;
1289 }
1290 }
1291 }
1292 Motion::RightWord => {
1293 let rtl_opt = self
1294 .line_shape(font_system, cursor.line)
1295 .map(|shape| shape.rtl);
1296 if let Some(rtl) = rtl_opt {
1297 if rtl {
1298 (cursor, cursor_x_opt) = self.cursor_motion(
1299 font_system,
1300 cursor,
1301 cursor_x_opt,
1302 Motion::PreviousWord,
1303 )?;
1304 } else {
1305 (cursor, cursor_x_opt) = self.cursor_motion(
1306 font_system,
1307 cursor,
1308 cursor_x_opt,
1309 Motion::NextWord,
1310 )?;
1311 }
1312 }
1313 }
1314 Motion::BufferStart => {
1315 cursor.line = 0;
1316 cursor.index = 0;
1317 cursor_x_opt = None;
1318 }
1319 Motion::BufferEnd => {
1320 cursor.line = self.lines.len().saturating_sub(1);
1321 cursor.index = self.lines.get(cursor.line)?.text().len();
1322 cursor_x_opt = None;
1323 }
1324 Motion::GotoLine(line) => {
1325 let mut layout_cursor = self.layout_cursor(font_system, cursor)?;
1326 layout_cursor.line = line;
1327 (cursor, cursor_x_opt) = self.cursor_motion(
1328 font_system,
1329 cursor,
1330 cursor_x_opt,
1331 Motion::LayoutCursor(layout_cursor),
1332 )?;
1333 }
1334 }
1335 Some((cursor, cursor_x_opt))
1336 }
1337
1338 #[cfg(feature = "swash")]
1340 pub fn draw<F>(
1341 &self,
1342 font_system: &mut FontSystem,
1343 cache: &mut crate::SwashCache,
1344 color: Color,
1345 mut f: F,
1346 ) where
1347 F: FnMut(i32, i32, u32, u32, Color),
1348 {
1349 for run in self.layout_runs() {
1350 for glyph in run.glyphs {
1351 let physical_glyph = glyph.physical((0., 0.), 1.0);
1352 let glyph_color = glyph.color_opt.map_or(color, |some| some);
1353
1354 cache.with_pixels(
1355 font_system,
1356 physical_glyph.cache_key,
1357 glyph_color,
1358 |x, y, color| {
1359 f(
1360 physical_glyph.x + x,
1361 run.line_y as i32 + physical_glyph.y + y,
1362 1,
1363 1,
1364 color,
1365 );
1366 },
1367 );
1368 }
1369 }
1370 }
1371}
1372
1373impl BorrowedWithFontSystem<'_, Buffer> {
1374 pub fn shape_until_cursor(&mut self, cursor: Cursor, prune: bool) {
1376 self.inner
1377 .shape_until_cursor(self.font_system, cursor, prune);
1378 }
1379
1380 pub fn shape_until_scroll(&mut self, prune: bool) {
1382 self.inner.shape_until_scroll(self.font_system, prune);
1383 }
1384
1385 pub fn line_shape(&mut self, line_i: usize) -> Option<&ShapeLine> {
1387 self.inner.line_shape(self.font_system, line_i)
1388 }
1389
1390 pub fn line_layout(&mut self, line_i: usize) -> Option<&[LayoutLine]> {
1392 self.inner.line_layout(self.font_system, line_i)
1393 }
1394
1395 pub fn set_metrics(&mut self, metrics: Metrics) {
1401 self.inner.set_metrics(self.font_system, metrics);
1402 }
1403
1404 pub fn set_wrap(&mut self, wrap: Wrap) {
1406 self.inner.set_wrap(self.font_system, wrap);
1407 }
1408
1409 pub fn set_size(&mut self, width_opt: Option<f32>, height_opt: Option<f32>) {
1411 self.inner.set_size(self.font_system, width_opt, height_opt);
1412 }
1413
1414 pub fn set_metrics_and_size(
1420 &mut self,
1421 metrics: Metrics,
1422 width_opt: Option<f32>,
1423 height_opt: Option<f32>,
1424 ) {
1425 self.inner
1426 .set_metrics_and_size(self.font_system, metrics, width_opt, height_opt);
1427 }
1428
1429 pub fn set_tab_width(&mut self, tab_width: u16) {
1431 self.inner.set_tab_width(self.font_system, tab_width);
1432 }
1433
1434 pub fn set_text(
1436 &mut self,
1437 text: &str,
1438 attrs: &Attrs,
1439 shaping: Shaping,
1440 alignment: Option<Align>,
1441 ) {
1442 self.inner
1443 .set_text(self.font_system, text, attrs, shaping, alignment);
1444 }
1445
1446 pub fn set_rich_text<'r, 's, I>(
1465 &mut self,
1466 spans: I,
1467 default_attrs: &Attrs,
1468 shaping: Shaping,
1469 alignment: Option<Align>,
1470 ) where
1471 I: IntoIterator<Item = (&'s str, Attrs<'r>)>,
1472 {
1473 self.inner
1474 .set_rich_text(self.font_system, spans, default_attrs, shaping, alignment);
1475 }
1476
1477 pub fn cursor_motion(
1479 &mut self,
1480 cursor: Cursor,
1481 cursor_x_opt: Option<i32>,
1482 motion: Motion,
1483 ) -> Option<(Cursor, Option<i32>)> {
1484 self.inner
1485 .cursor_motion(self.font_system, cursor, cursor_x_opt, motion)
1486 }
1487
1488 #[cfg(feature = "swash")]
1490 pub fn draw<F>(&mut self, cache: &mut crate::SwashCache, color: Color, f: F)
1491 where
1492 F: FnMut(i32, i32, u32, u32, Color),
1493 {
1494 self.inner.draw(self.font_system, cache, color, f);
1495 }
1496}