1use super::{
2 DisplayPoint, DisplayRow, Editor, EditorMode, EditorSettings, EditorStyle, Input, Scroll,
3 Select, SelectPhase, Snapshot, SoftWrap, MAX_LINE_LEN,
4};
5use clock::ReplicaId;
6use gpui::{
7 color::Color,
8 geometry::{
9 rect::RectF,
10 vector::{vec2f, Vector2F},
11 PathBuilder,
12 },
13 json::{self, ToJson},
14 keymap::Keystroke,
15 text_layout::{self, RunStyle, TextLayoutCache},
16 AppContext, Axis, Border, Element, Event, EventContext, FontCache, LayoutContext,
17 MutableAppContext, PaintContext, Quad, Scene, SizeConstraint, ViewContext, WeakViewHandle,
18};
19use json::json;
20use language::Chunk;
21use smallvec::SmallVec;
22use std::{
23 cmp::{self, Ordering},
24 collections::{BTreeMap, HashMap},
25 fmt::Write,
26 ops::Range,
27};
28use theme::BlockStyle;
29
30pub struct EditorElement {
31 view: WeakViewHandle<Editor>,
32 settings: EditorSettings,
33}
34
35impl EditorElement {
36 pub fn new(view: WeakViewHandle<Editor>, settings: EditorSettings) -> Self {
37 Self { view, settings }
38 }
39
40 fn view<'a>(&self, cx: &'a AppContext) -> &'a Editor {
41 self.view.upgrade(cx).unwrap().read(cx)
42 }
43
44 fn update_view<F, T>(&self, cx: &mut MutableAppContext, f: F) -> T
45 where
46 F: FnOnce(&mut Editor, &mut ViewContext<Editor>) -> T,
47 {
48 self.view.upgrade(cx).unwrap().update(cx, f)
49 }
50
51 fn snapshot(&self, cx: &mut MutableAppContext) -> Snapshot {
52 self.update_view(cx, |view, cx| view.snapshot(cx))
53 }
54
55 fn mouse_down(
56 &self,
57 position: Vector2F,
58 alt: bool,
59 shift: bool,
60 mut click_count: usize,
61 layout: &mut LayoutState,
62 paint: &mut PaintState,
63 cx: &mut EventContext,
64 ) -> bool {
65 if paint.gutter_bounds.contains_point(position) {
66 click_count = 3; // Simulate triple-click when clicking the gutter to select lines
67 } else if !paint.text_bounds.contains_point(position) {
68 return false;
69 }
70
71 let snapshot = self.snapshot(cx.app);
72 let (position, overshoot) = paint.point_for_position(&snapshot, layout, position);
73
74 if shift && alt {
75 cx.dispatch_action(Select(SelectPhase::BeginColumnar {
76 position,
77 overshoot,
78 }));
79 } else if shift {
80 cx.dispatch_action(Select(SelectPhase::Extend {
81 position,
82 click_count,
83 }));
84 } else {
85 cx.dispatch_action(Select(SelectPhase::Begin {
86 position,
87 add: alt,
88 click_count,
89 }));
90 }
91
92 true
93 }
94
95 fn mouse_up(&self, _position: Vector2F, cx: &mut EventContext) -> bool {
96 if self.view(cx.app.as_ref()).is_selecting() {
97 cx.dispatch_action(Select(SelectPhase::End));
98 true
99 } else {
100 false
101 }
102 }
103
104 fn mouse_dragged(
105 &self,
106 position: Vector2F,
107 layout: &mut LayoutState,
108 paint: &mut PaintState,
109 cx: &mut EventContext,
110 ) -> bool {
111 let view = self.view(cx.app.as_ref());
112
113 if view.is_selecting() {
114 let rect = paint.text_bounds;
115 let mut scroll_delta = Vector2F::zero();
116
117 let vertical_margin = layout.line_height.min(rect.height() / 3.0);
118 let top = rect.origin_y() + vertical_margin;
119 let bottom = rect.lower_left().y() - vertical_margin;
120 if position.y() < top {
121 scroll_delta.set_y(-scale_vertical_mouse_autoscroll_delta(top - position.y()))
122 }
123 if position.y() > bottom {
124 scroll_delta.set_y(scale_vertical_mouse_autoscroll_delta(position.y() - bottom))
125 }
126
127 let horizontal_margin = layout.line_height.min(rect.width() / 3.0);
128 let left = rect.origin_x() + horizontal_margin;
129 let right = rect.upper_right().x() - horizontal_margin;
130 if position.x() < left {
131 scroll_delta.set_x(-scale_horizontal_mouse_autoscroll_delta(
132 left - position.x(),
133 ))
134 }
135 if position.x() > right {
136 scroll_delta.set_x(scale_horizontal_mouse_autoscroll_delta(
137 position.x() - right,
138 ))
139 }
140
141 let font_cache = cx.font_cache.clone();
142 let text_layout_cache = cx.text_layout_cache.clone();
143 let snapshot = self.snapshot(cx.app);
144 let (position, overshoot) = paint.point_for_position(&snapshot, layout, position);
145
146 cx.dispatch_action(Select(SelectPhase::Update {
147 position,
148 overshoot,
149 scroll_position: (snapshot.scroll_position() + scroll_delta).clamp(
150 Vector2F::zero(),
151 layout.scroll_max(&font_cache, &text_layout_cache),
152 ),
153 }));
154 true
155 } else {
156 false
157 }
158 }
159
160 fn key_down(&self, chars: &str, keystroke: &Keystroke, cx: &mut EventContext) -> bool {
161 let view = self.view.upgrade(cx.app).unwrap();
162
163 if view.is_focused(cx.app) {
164 if chars.is_empty() {
165 false
166 } else {
167 if chars.chars().any(|c| c.is_control()) || keystroke.cmd || keystroke.ctrl {
168 false
169 } else {
170 cx.dispatch_action(Input(chars.to_string()));
171 true
172 }
173 }
174 } else {
175 false
176 }
177 }
178
179 fn scroll(
180 &self,
181 position: Vector2F,
182 mut delta: Vector2F,
183 precise: bool,
184 layout: &mut LayoutState,
185 paint: &mut PaintState,
186 cx: &mut EventContext,
187 ) -> bool {
188 if !paint.bounds.contains_point(position) {
189 return false;
190 }
191
192 let snapshot = self.snapshot(cx.app);
193 let font_cache = &cx.font_cache;
194 let layout_cache = &cx.text_layout_cache;
195 let max_glyph_width = layout.em_width;
196 if !precise {
197 delta *= vec2f(max_glyph_width, layout.line_height);
198 }
199
200 let scroll_position = snapshot.scroll_position();
201 let x = (scroll_position.x() * max_glyph_width - delta.x()) / max_glyph_width;
202 let y = (scroll_position.y() * layout.line_height - delta.y()) / layout.line_height;
203 let scroll_position = vec2f(x, y).clamp(
204 Vector2F::zero(),
205 layout.scroll_max(font_cache, layout_cache),
206 );
207
208 cx.dispatch_action(Scroll(scroll_position));
209
210 true
211 }
212
213 fn paint_background(
214 &self,
215 gutter_bounds: RectF,
216 text_bounds: RectF,
217 layout: &LayoutState,
218 cx: &mut PaintContext,
219 ) {
220 let bounds = gutter_bounds.union_rect(text_bounds);
221 let scroll_top = layout.snapshot.scroll_position().y() * layout.line_height;
222 let start_row = layout.snapshot.scroll_position().y() as u32;
223 let editor = self.view(cx.app);
224 let style = &self.settings.style;
225 cx.scene.push_quad(Quad {
226 bounds: gutter_bounds,
227 background: Some(style.gutter_background),
228 border: Border::new(0., Color::transparent_black()),
229 corner_radius: 0.,
230 });
231 cx.scene.push_quad(Quad {
232 bounds: text_bounds,
233 background: Some(style.background),
234 border: Border::new(0., Color::transparent_black()),
235 corner_radius: 0.,
236 });
237
238 if let EditorMode::Full = editor.mode {
239 let mut active_rows = layout.active_rows.iter().peekable();
240 while let Some((start_row, contains_non_empty_selection)) = active_rows.next() {
241 let mut end_row = *start_row;
242 while active_rows.peek().map_or(false, |r| {
243 *r.0 == end_row + 1 && r.1 == contains_non_empty_selection
244 }) {
245 active_rows.next().unwrap();
246 end_row += 1;
247 }
248
249 if !contains_non_empty_selection {
250 let origin = vec2f(
251 bounds.origin_x(),
252 bounds.origin_y() + (layout.line_height * *start_row as f32) - scroll_top,
253 );
254 let size = vec2f(
255 bounds.width(),
256 layout.line_height * (end_row - start_row + 1) as f32,
257 );
258 cx.scene.push_quad(Quad {
259 bounds: RectF::new(origin, size),
260 background: Some(style.active_line_background),
261 border: Border::default(),
262 corner_radius: 0.,
263 });
264 }
265 }
266
267 if let Some(highlighted_row) = layout.highlighted_row {
268 let origin = vec2f(
269 bounds.origin_x(),
270 bounds.origin_y() + (layout.line_height * highlighted_row as f32) - scroll_top,
271 );
272 let size = vec2f(bounds.width(), layout.line_height);
273 cx.scene.push_quad(Quad {
274 bounds: RectF::new(origin, size),
275 background: Some(style.highlighted_line_background),
276 border: Border::default(),
277 corner_radius: 0.,
278 });
279 }
280 }
281
282 // Draw block backgrounds
283 for (ixs, block_style) in &layout.block_layouts {
284 let row = start_row + ixs.start;
285 let offset = vec2f(0., row as f32 * layout.line_height - scroll_top);
286 let height = ixs.len() as f32 * layout.line_height;
287 cx.scene.push_quad(Quad {
288 bounds: RectF::new(
289 text_bounds.origin() + offset,
290 vec2f(text_bounds.width(), height),
291 ),
292 background: block_style.background,
293 border: block_style
294 .border
295 .map_or(Default::default(), |color| Border {
296 width: 1.,
297 color,
298 overlay: true,
299 top: true,
300 right: false,
301 bottom: true,
302 left: false,
303 }),
304 corner_radius: 0.,
305 });
306 cx.scene.push_quad(Quad {
307 bounds: RectF::new(
308 gutter_bounds.origin() + offset,
309 vec2f(gutter_bounds.width(), height),
310 ),
311 background: block_style.gutter_background,
312 border: block_style
313 .gutter_border
314 .map_or(Default::default(), |color| Border {
315 width: 1.,
316 color,
317 overlay: true,
318 top: true,
319 right: false,
320 bottom: true,
321 left: false,
322 }),
323 corner_radius: 0.,
324 });
325 }
326 }
327
328 fn paint_gutter(
329 &mut self,
330 bounds: RectF,
331 visible_bounds: RectF,
332 layout: &LayoutState,
333 cx: &mut PaintContext,
334 ) {
335 let scroll_top = layout.snapshot.scroll_position().y() * layout.line_height;
336 for (ix, line) in layout.line_number_layouts.iter().enumerate() {
337 if let Some(line) = line {
338 let line_origin = bounds.origin()
339 + vec2f(
340 bounds.width() - line.width() - layout.gutter_padding,
341 ix as f32 * layout.line_height - (scroll_top % layout.line_height),
342 );
343 line.paint(line_origin, visible_bounds, layout.line_height, cx);
344 }
345 }
346 }
347
348 fn paint_text(
349 &mut self,
350 bounds: RectF,
351 visible_bounds: RectF,
352 layout: &LayoutState,
353 cx: &mut PaintContext,
354 ) {
355 let view = self.view(cx.app);
356 let style = &self.settings.style;
357 let local_replica_id = view.replica_id(cx);
358 let scroll_position = layout.snapshot.scroll_position();
359 let start_row = scroll_position.y() as u32;
360 let scroll_top = scroll_position.y() * layout.line_height;
361 let end_row = ((scroll_top + bounds.height()) / layout.line_height).ceil() as u32 + 1; // Add 1 to ensure selections bleed off screen
362 let max_glyph_width = layout.em_width;
363 let scroll_left = scroll_position.x() * max_glyph_width;
364
365 cx.scene.push_layer(Some(bounds));
366
367 // Draw selections
368 let corner_radius = 2.5;
369 let mut cursors = SmallVec::<[Cursor; 32]>::new();
370
371 let content_origin = bounds.origin() + layout.text_offset;
372
373 for (replica_id, selections) in &layout.selections {
374 let style = style.replica_selection_style(*replica_id);
375
376 for selection in selections {
377 if selection.start != selection.end {
378 let row_range = if selection.end.column() == 0 {
379 cmp::max(selection.start.row(), start_row)
380 ..cmp::min(selection.end.row(), end_row)
381 } else {
382 cmp::max(selection.start.row(), start_row)
383 ..cmp::min(selection.end.row() + 1, end_row)
384 };
385
386 let selection = Selection {
387 color: style.selection,
388 line_height: layout.line_height,
389 start_y: content_origin.y() + row_range.start as f32 * layout.line_height
390 - scroll_top,
391 lines: row_range
392 .into_iter()
393 .map(|row| {
394 let line_layout = &layout.line_layouts[(row - start_row) as usize];
395 SelectionLine {
396 start_x: if row == selection.start.row() {
397 content_origin.x()
398 + line_layout
399 .x_for_index(selection.start.column() as usize)
400 - scroll_left
401 } else {
402 content_origin.x() - scroll_left
403 },
404 end_x: if row == selection.end.row() {
405 content_origin.x()
406 + line_layout
407 .x_for_index(selection.end.column() as usize)
408 - scroll_left
409 } else {
410 content_origin.x()
411 + line_layout.width()
412 + corner_radius * 2.0
413 - scroll_left
414 },
415 }
416 })
417 .collect(),
418 };
419
420 selection.paint(bounds, cx.scene);
421 }
422
423 if view.show_local_cursors() || *replica_id != local_replica_id {
424 let cursor_position = selection.head();
425 if (start_row..end_row).contains(&cursor_position.row()) {
426 let cursor_row_layout =
427 &layout.line_layouts[(cursor_position.row() - start_row) as usize];
428 let x = cursor_row_layout.x_for_index(cursor_position.column() as usize)
429 - scroll_left;
430 let y = cursor_position.row() as f32 * layout.line_height - scroll_top;
431 cursors.push(Cursor {
432 color: style.cursor,
433 origin: content_origin + vec2f(x, y),
434 line_height: layout.line_height,
435 });
436 }
437 }
438 }
439 }
440
441 if let Some(visible_text_bounds) = bounds.intersection(visible_bounds) {
442 // Draw glyphs
443 for (ix, line) in layout.line_layouts.iter().enumerate() {
444 let row = start_row + ix as u32;
445 line.paint(
446 content_origin
447 + vec2f(-scroll_left, row as f32 * layout.line_height - scroll_top),
448 visible_text_bounds,
449 layout.line_height,
450 cx,
451 );
452 }
453 }
454
455 cx.scene.push_layer(Some(bounds));
456 for cursor in cursors {
457 cursor.paint(cx);
458 }
459 cx.scene.pop_layer();
460
461 cx.scene.pop_layer();
462 }
463
464 fn max_line_number_width(&self, snapshot: &Snapshot, cx: &LayoutContext) -> f32 {
465 let digit_count = (snapshot.buffer_row_count() as f32).log10().floor() as usize + 1;
466 let style = &self.settings.style;
467
468 cx.text_layout_cache
469 .layout_str(
470 "1".repeat(digit_count).as_str(),
471 style.text.font_size,
472 &[(
473 digit_count,
474 RunStyle {
475 font_id: style.text.font_id,
476 color: Color::black(),
477 underline: None,
478 },
479 )],
480 )
481 .width()
482 }
483
484 fn layout_rows(
485 &self,
486 rows: Range<u32>,
487 active_rows: &BTreeMap<u32, bool>,
488 snapshot: &Snapshot,
489 cx: &LayoutContext,
490 ) -> (
491 Vec<Option<text_layout::Line>>,
492 Vec<(Range<u32>, BlockStyle)>,
493 ) {
494 let style = &self.settings.style;
495 let include_line_numbers = snapshot.mode == EditorMode::Full;
496 let mut last_block_id = None;
497 let mut blocks = Vec::<(Range<u32>, BlockStyle)>::new();
498 let mut line_number_layouts = Vec::with_capacity(rows.len());
499 let mut line_number = String::new();
500 for (ix, row) in snapshot
501 .buffer_rows(rows.start, cx)
502 .take((rows.end - rows.start) as usize)
503 .enumerate()
504 {
505 let display_row = rows.start + ix as u32;
506 let color = if active_rows.contains_key(&display_row) {
507 style.line_number_active
508 } else {
509 style.line_number
510 };
511 match row {
512 DisplayRow::Buffer(buffer_row) => {
513 if include_line_numbers {
514 line_number.clear();
515 write!(&mut line_number, "{}", buffer_row + 1).unwrap();
516 line_number_layouts.push(Some(cx.text_layout_cache.layout_str(
517 &line_number,
518 style.text.font_size,
519 &[(
520 line_number.len(),
521 RunStyle {
522 font_id: style.text.font_id,
523 color,
524 underline: None,
525 },
526 )],
527 )));
528 }
529 last_block_id = None;
530 }
531 DisplayRow::Block(block_id, style) => {
532 let ix = ix as u32;
533 if last_block_id == Some(block_id) {
534 if let Some((row_range, _)) = blocks.last_mut() {
535 row_range.end += 1;
536 }
537 } else if let Some(style) = style {
538 blocks.push((ix..ix + 1, style));
539 }
540 line_number_layouts.push(None);
541 last_block_id = Some(block_id);
542 }
543 DisplayRow::Wrap => {
544 line_number_layouts.push(None);
545 last_block_id = None;
546 }
547 }
548 }
549
550 (line_number_layouts, blocks)
551 }
552
553 fn layout_lines(
554 &mut self,
555 mut rows: Range<u32>,
556 snapshot: &mut Snapshot,
557 cx: &LayoutContext,
558 ) -> Vec<text_layout::Line> {
559 rows.end = cmp::min(rows.end, snapshot.max_point().row() + 1);
560 if rows.start >= rows.end {
561 return Vec::new();
562 }
563
564 // When the editor is empty and unfocused, then show the placeholder.
565 if snapshot.is_empty() && !snapshot.is_focused() {
566 let placeholder_style = self.settings.style.placeholder_text();
567 let placeholder_text = snapshot.placeholder_text();
568 let placeholder_lines = placeholder_text
569 .as_ref()
570 .map_or("", AsRef::as_ref)
571 .split('\n')
572 .skip(rows.start as usize)
573 .take(rows.len());
574 return placeholder_lines
575 .map(|line| {
576 cx.text_layout_cache.layout_str(
577 line,
578 placeholder_style.font_size,
579 &[(
580 line.len(),
581 RunStyle {
582 font_id: placeholder_style.font_id,
583 color: placeholder_style.color,
584 underline: None,
585 },
586 )],
587 )
588 })
589 .collect();
590 }
591
592 let style = &self.settings.style;
593 let mut prev_font_properties = style.text.font_properties.clone();
594 let mut prev_font_id = style.text.font_id;
595
596 let mut layouts = Vec::with_capacity(rows.len());
597 let mut line = String::new();
598 let mut styles = Vec::new();
599 let mut row = rows.start;
600 let mut line_exceeded_max_len = false;
601 let chunks = snapshot.chunks(rows.clone(), Some(&style.syntax), cx);
602
603 let newline_chunk = Chunk {
604 text: "\n",
605 ..Default::default()
606 };
607 'outer: for chunk in chunks.chain([newline_chunk]) {
608 for (ix, mut line_chunk) in chunk.text.split('\n').enumerate() {
609 if ix > 0 {
610 layouts.push(cx.text_layout_cache.layout_str(
611 &line,
612 style.text.font_size,
613 &styles,
614 ));
615 line.clear();
616 styles.clear();
617 row += 1;
618 line_exceeded_max_len = false;
619 if row == rows.end {
620 break 'outer;
621 }
622 }
623
624 if !line_chunk.is_empty() && !line_exceeded_max_len {
625 let highlight_style =
626 chunk.highlight_style.unwrap_or(style.text.clone().into());
627 // Avoid a lookup if the font properties match the previous ones.
628 let font_id = if highlight_style.font_properties == prev_font_properties {
629 prev_font_id
630 } else {
631 cx.font_cache
632 .select_font(
633 style.text.font_family_id,
634 &highlight_style.font_properties,
635 )
636 .unwrap_or(style.text.font_id)
637 };
638
639 if line.len() + line_chunk.len() > MAX_LINE_LEN {
640 let mut chunk_len = MAX_LINE_LEN - line.len();
641 while !line_chunk.is_char_boundary(chunk_len) {
642 chunk_len -= 1;
643 }
644 line_chunk = &line_chunk[..chunk_len];
645 line_exceeded_max_len = true;
646 }
647
648 let underline = if let Some(severity) = chunk.diagnostic {
649 Some(super::diagnostic_style(severity, true, style).text)
650 } else {
651 highlight_style.underline
652 };
653
654 line.push_str(line_chunk);
655 styles.push((
656 line_chunk.len(),
657 RunStyle {
658 font_id,
659 color: highlight_style.color,
660 underline,
661 },
662 ));
663 prev_font_id = font_id;
664 prev_font_properties = highlight_style.font_properties;
665 }
666 }
667 }
668
669 layouts
670 }
671}
672
673impl Element for EditorElement {
674 type LayoutState = Option<LayoutState>;
675 type PaintState = Option<PaintState>;
676
677 fn layout(
678 &mut self,
679 constraint: SizeConstraint,
680 cx: &mut LayoutContext,
681 ) -> (Vector2F, Self::LayoutState) {
682 let mut size = constraint.max;
683 if size.x().is_infinite() {
684 unimplemented!("we don't yet handle an infinite width constraint on buffer elements");
685 }
686
687 let snapshot = self.snapshot(cx.app);
688 let style = self.settings.style.clone();
689 let line_height = style.text.line_height(cx.font_cache);
690
691 let gutter_padding;
692 let gutter_width;
693 if snapshot.mode == EditorMode::Full {
694 gutter_padding = style.text.em_width(cx.font_cache);
695 gutter_width = self.max_line_number_width(&snapshot, cx) + gutter_padding * 2.0;
696 } else {
697 gutter_padding = 0.0;
698 gutter_width = 0.0
699 };
700
701 let text_width = size.x() - gutter_width;
702 let text_offset = vec2f(-style.text.descent(cx.font_cache), 0.);
703 let em_width = style.text.em_width(cx.font_cache);
704 let em_advance = style.text.em_advance(cx.font_cache);
705 let overscroll = vec2f(em_width, 0.);
706 let wrap_width = match self.settings.soft_wrap {
707 SoftWrap::None => None,
708 SoftWrap::EditorWidth => Some(text_width - text_offset.x() - overscroll.x() - em_width),
709 SoftWrap::Column(column) => Some(column as f32 * em_advance),
710 };
711 let snapshot = self.update_view(cx.app, |view, cx| {
712 if view.set_wrap_width(wrap_width, cx) {
713 view.snapshot(cx)
714 } else {
715 snapshot
716 }
717 });
718
719 let scroll_height = (snapshot.max_point().row() + 1) as f32 * line_height;
720 if let EditorMode::AutoHeight { max_lines } = snapshot.mode {
721 size.set_y(
722 scroll_height
723 .min(constraint.max_along(Axis::Vertical))
724 .max(constraint.min_along(Axis::Vertical))
725 .min(line_height * max_lines as f32),
726 )
727 } else if size.y().is_infinite() {
728 size.set_y(scroll_height);
729 }
730 let gutter_size = vec2f(gutter_width, size.y());
731 let text_size = vec2f(text_width, size.y());
732
733 let (autoscroll_horizontally, mut snapshot) = self.update_view(cx.app, |view, cx| {
734 let autoscroll_horizontally = view.autoscroll_vertically(size.y(), line_height, cx);
735 let snapshot = view.snapshot(cx);
736 (autoscroll_horizontally, snapshot)
737 });
738
739 let scroll_position = snapshot.scroll_position();
740 let start_row = scroll_position.y() as u32;
741 let scroll_top = scroll_position.y() * line_height;
742 let end_row = ((scroll_top + size.y()) / line_height).ceil() as u32 + 1; // Add 1 to ensure selections bleed off screen
743
744 let mut selections = HashMap::new();
745 let mut active_rows = BTreeMap::new();
746 let mut highlighted_row = None;
747 self.update_view(cx.app, |view, cx| {
748 highlighted_row = view.highlighted_row();
749 for selection_set_id in view.active_selection_sets(cx).collect::<Vec<_>>() {
750 let replica_selections = view
751 .intersecting_selections(
752 selection_set_id,
753 DisplayPoint::new(start_row, 0)..DisplayPoint::new(end_row, 0),
754 cx,
755 )
756 .collect::<Vec<_>>();
757 for selection in &replica_selections {
758 if selection_set_id == view.selection_set_id {
759 let is_empty = selection.start == selection.end;
760 let selection_start = snapshot.prev_row_boundary(selection.start).0;
761 let selection_end = snapshot.next_row_boundary(selection.end).0;
762 for row in cmp::max(selection_start.row(), start_row)
763 ..=cmp::min(selection_end.row(), end_row)
764 {
765 let contains_non_empty_selection =
766 active_rows.entry(row).or_insert(!is_empty);
767 *contains_non_empty_selection |= !is_empty;
768 }
769 }
770 }
771
772 selections.insert(selection_set_id.replica_id, replica_selections);
773 }
774 });
775
776 let (line_number_layouts, block_layouts) =
777 self.layout_rows(start_row..end_row, &active_rows, &snapshot, cx);
778
779 let mut max_visible_line_width = 0.0;
780 let line_layouts = self.layout_lines(start_row..end_row, &mut snapshot, cx);
781 for line in &line_layouts {
782 if line.width() > max_visible_line_width {
783 max_visible_line_width = line.width();
784 }
785 }
786
787 let mut layout = LayoutState {
788 size,
789 gutter_size,
790 gutter_padding,
791 text_size,
792 overscroll,
793 text_offset,
794 snapshot,
795 style: self.settings.style.clone(),
796 active_rows,
797 highlighted_row,
798 line_layouts,
799 line_number_layouts,
800 block_layouts,
801 line_height,
802 em_width,
803 em_advance,
804 selections,
805 max_visible_line_width,
806 };
807
808 let scroll_max = layout.scroll_max(cx.font_cache, cx.text_layout_cache).x();
809 let scroll_width = layout.scroll_width(cx.text_layout_cache);
810 let max_glyph_width = style.text.em_width(&cx.font_cache);
811 self.update_view(cx.app, |view, cx| {
812 let clamped = view.clamp_scroll_left(scroll_max);
813 let autoscrolled;
814 if autoscroll_horizontally {
815 autoscrolled = view.autoscroll_horizontally(
816 start_row,
817 layout.text_size.x(),
818 scroll_width,
819 max_glyph_width,
820 &layout.line_layouts,
821 cx,
822 );
823 } else {
824 autoscrolled = false;
825 }
826
827 if clamped || autoscrolled {
828 layout.snapshot = view.snapshot(cx);
829 }
830 });
831
832 (size, Some(layout))
833 }
834
835 fn paint(
836 &mut self,
837 bounds: RectF,
838 visible_bounds: RectF,
839 layout: &mut Self::LayoutState,
840 cx: &mut PaintContext,
841 ) -> Self::PaintState {
842 if let Some(layout) = layout {
843 cx.scene.push_layer(Some(bounds));
844
845 let gutter_bounds = RectF::new(bounds.origin(), layout.gutter_size);
846 let text_bounds = RectF::new(
847 bounds.origin() + vec2f(layout.gutter_size.x(), 0.0),
848 layout.text_size,
849 );
850
851 self.paint_background(gutter_bounds, text_bounds, layout, cx);
852 if layout.gutter_size.x() > 0. {
853 self.paint_gutter(gutter_bounds, visible_bounds, layout, cx);
854 }
855 self.paint_text(text_bounds, visible_bounds, layout, cx);
856
857 cx.scene.pop_layer();
858
859 Some(PaintState {
860 bounds,
861 gutter_bounds,
862 text_bounds,
863 })
864 } else {
865 None
866 }
867 }
868
869 fn dispatch_event(
870 &mut self,
871 event: &Event,
872 _: RectF,
873 layout: &mut Self::LayoutState,
874 paint: &mut Self::PaintState,
875 cx: &mut EventContext,
876 ) -> bool {
877 if let (Some(layout), Some(paint)) = (layout, paint) {
878 match event {
879 Event::LeftMouseDown {
880 position,
881 alt,
882 shift,
883 click_count,
884 ..
885 } => self.mouse_down(*position, *alt, *shift, *click_count, layout, paint, cx),
886 Event::LeftMouseUp { position } => self.mouse_up(*position, cx),
887 Event::LeftMouseDragged { position } => {
888 self.mouse_dragged(*position, layout, paint, cx)
889 }
890 Event::ScrollWheel {
891 position,
892 delta,
893 precise,
894 } => self.scroll(*position, *delta, *precise, layout, paint, cx),
895 Event::KeyDown {
896 chars, keystroke, ..
897 } => self.key_down(chars, keystroke, cx),
898 _ => false,
899 }
900 } else {
901 false
902 }
903 }
904
905 fn debug(
906 &self,
907 bounds: RectF,
908 _: &Self::LayoutState,
909 _: &Self::PaintState,
910 _: &gpui::DebugContext,
911 ) -> json::Value {
912 json!({
913 "type": "BufferElement",
914 "bounds": bounds.to_json()
915 })
916 }
917}
918
919pub struct LayoutState {
920 size: Vector2F,
921 gutter_size: Vector2F,
922 gutter_padding: f32,
923 text_size: Vector2F,
924 style: EditorStyle,
925 snapshot: Snapshot,
926 active_rows: BTreeMap<u32, bool>,
927 highlighted_row: Option<u32>,
928 line_layouts: Vec<text_layout::Line>,
929 line_number_layouts: Vec<Option<text_layout::Line>>,
930 block_layouts: Vec<(Range<u32>, BlockStyle)>,
931 line_height: f32,
932 em_width: f32,
933 em_advance: f32,
934 selections: HashMap<ReplicaId, Vec<text::Selection<DisplayPoint>>>,
935 overscroll: Vector2F,
936 text_offset: Vector2F,
937 max_visible_line_width: f32,
938}
939
940impl LayoutState {
941 fn scroll_width(&self, layout_cache: &TextLayoutCache) -> f32 {
942 let row = self.snapshot.longest_row();
943 let longest_line_width = self.layout_line(row, &self.snapshot, layout_cache).width();
944 longest_line_width.max(self.max_visible_line_width) + self.overscroll.x()
945 }
946
947 fn scroll_max(&self, font_cache: &FontCache, layout_cache: &TextLayoutCache) -> Vector2F {
948 let text_width = self.text_size.x();
949 let scroll_width = self.scroll_width(layout_cache);
950 let em_width = self.style.text.em_width(font_cache);
951 let max_row = self.snapshot.max_point().row();
952
953 vec2f(
954 ((scroll_width - text_width) / em_width).max(0.0),
955 max_row.saturating_sub(1) as f32,
956 )
957 }
958
959 pub fn layout_line(
960 &self,
961 row: u32,
962 snapshot: &Snapshot,
963 layout_cache: &TextLayoutCache,
964 ) -> text_layout::Line {
965 let mut line = snapshot.line(row);
966
967 if line.len() > MAX_LINE_LEN {
968 let mut len = MAX_LINE_LEN;
969 while !line.is_char_boundary(len) {
970 len -= 1;
971 }
972 line.truncate(len);
973 }
974
975 layout_cache.layout_str(
976 &line,
977 self.style.text.font_size,
978 &[(
979 snapshot.line_len(row) as usize,
980 RunStyle {
981 font_id: self.style.text.font_id,
982 color: Color::black(),
983 underline: None,
984 },
985 )],
986 )
987 }
988}
989
990pub struct PaintState {
991 bounds: RectF,
992 gutter_bounds: RectF,
993 text_bounds: RectF,
994}
995
996impl PaintState {
997 fn point_for_position(
998 &self,
999 snapshot: &Snapshot,
1000 layout: &LayoutState,
1001 position: Vector2F,
1002 ) -> (DisplayPoint, u32) {
1003 let scroll_position = snapshot.scroll_position();
1004 let position = position - self.text_bounds.origin();
1005 let y = position.y().max(0.0).min(layout.size.y());
1006 let row = ((y / layout.line_height) + scroll_position.y()) as u32;
1007 let row = cmp::min(row, snapshot.max_point().row());
1008 let line = &layout.line_layouts[(row - scroll_position.y() as u32) as usize];
1009 let x = position.x() + (scroll_position.x() * layout.em_width);
1010
1011 let column = if x >= 0.0 {
1012 line.index_for_x(x)
1013 .map(|ix| ix as u32)
1014 .unwrap_or_else(|| snapshot.line_len(row))
1015 } else {
1016 0
1017 };
1018 let overshoot = (0f32.max(x - line.width()) / layout.em_advance) as u32;
1019
1020 (DisplayPoint::new(row, column), overshoot)
1021 }
1022}
1023
1024struct Cursor {
1025 origin: Vector2F,
1026 line_height: f32,
1027 color: Color,
1028}
1029
1030impl Cursor {
1031 fn paint(&self, cx: &mut PaintContext) {
1032 cx.scene.push_quad(Quad {
1033 bounds: RectF::new(self.origin, vec2f(2.0, self.line_height)),
1034 background: Some(self.color),
1035 border: Border::new(0., Color::black()),
1036 corner_radius: 0.,
1037 });
1038 }
1039}
1040
1041#[derive(Debug)]
1042struct Selection {
1043 start_y: f32,
1044 line_height: f32,
1045 lines: Vec<SelectionLine>,
1046 color: Color,
1047}
1048
1049#[derive(Debug)]
1050struct SelectionLine {
1051 start_x: f32,
1052 end_x: f32,
1053}
1054
1055impl Selection {
1056 fn paint(&self, bounds: RectF, scene: &mut Scene) {
1057 if self.lines.len() >= 2 && self.lines[0].start_x > self.lines[1].end_x {
1058 self.paint_lines(self.start_y, &self.lines[0..1], bounds, scene);
1059 self.paint_lines(
1060 self.start_y + self.line_height,
1061 &self.lines[1..],
1062 bounds,
1063 scene,
1064 );
1065 } else {
1066 self.paint_lines(self.start_y, &self.lines, bounds, scene);
1067 }
1068 }
1069
1070 fn paint_lines(&self, start_y: f32, lines: &[SelectionLine], bounds: RectF, scene: &mut Scene) {
1071 if lines.is_empty() {
1072 return;
1073 }
1074
1075 let mut path = PathBuilder::new();
1076 let corner_radius = 0.15 * self.line_height;
1077 let first_line = lines.first().unwrap();
1078 let last_line = lines.last().unwrap();
1079
1080 let first_top_left = vec2f(first_line.start_x, start_y);
1081 let first_top_right = vec2f(first_line.end_x, start_y);
1082
1083 let curve_height = vec2f(0., corner_radius);
1084 let curve_width = |start_x: f32, end_x: f32| {
1085 let max = (end_x - start_x) / 2.;
1086 let width = if max < corner_radius {
1087 max
1088 } else {
1089 corner_radius
1090 };
1091
1092 vec2f(width, 0.)
1093 };
1094
1095 let top_curve_width = curve_width(first_line.start_x, first_line.end_x);
1096 path.reset(first_top_right - top_curve_width);
1097 path.curve_to(first_top_right + curve_height, first_top_right);
1098
1099 let mut iter = lines.iter().enumerate().peekable();
1100 while let Some((ix, line)) = iter.next() {
1101 let bottom_right = vec2f(line.end_x, start_y + (ix + 1) as f32 * self.line_height);
1102
1103 if let Some((_, next_line)) = iter.peek() {
1104 let next_top_right = vec2f(next_line.end_x, bottom_right.y());
1105
1106 match next_top_right.x().partial_cmp(&bottom_right.x()).unwrap() {
1107 Ordering::Equal => {
1108 path.line_to(bottom_right);
1109 }
1110 Ordering::Less => {
1111 let curve_width = curve_width(next_top_right.x(), bottom_right.x());
1112 path.line_to(bottom_right - curve_height);
1113 path.curve_to(bottom_right - curve_width, bottom_right);
1114 path.line_to(next_top_right + curve_width);
1115 path.curve_to(next_top_right + curve_height, next_top_right);
1116 }
1117 Ordering::Greater => {
1118 let curve_width = curve_width(bottom_right.x(), next_top_right.x());
1119 path.line_to(bottom_right - curve_height);
1120 path.curve_to(bottom_right + curve_width, bottom_right);
1121 path.line_to(next_top_right - curve_width);
1122 path.curve_to(next_top_right + curve_height, next_top_right);
1123 }
1124 }
1125 } else {
1126 let curve_width = curve_width(line.start_x, line.end_x);
1127 path.line_to(bottom_right - curve_height);
1128 path.curve_to(bottom_right - curve_width, bottom_right);
1129
1130 let bottom_left = vec2f(line.start_x, bottom_right.y());
1131 path.line_to(bottom_left + curve_width);
1132 path.curve_to(bottom_left - curve_height, bottom_left);
1133 }
1134 }
1135
1136 if first_line.start_x > last_line.start_x {
1137 let curve_width = curve_width(last_line.start_x, first_line.start_x);
1138 let second_top_left = vec2f(last_line.start_x, start_y + self.line_height);
1139 path.line_to(second_top_left + curve_height);
1140 path.curve_to(second_top_left + curve_width, second_top_left);
1141 let first_bottom_left = vec2f(first_line.start_x, second_top_left.y());
1142 path.line_to(first_bottom_left - curve_width);
1143 path.curve_to(first_bottom_left - curve_height, first_bottom_left);
1144 }
1145
1146 path.line_to(first_top_left + curve_height);
1147 path.curve_to(first_top_left + top_curve_width, first_top_left);
1148 path.line_to(first_top_right - top_curve_width);
1149
1150 scene.push_path(path.build(self.color, Some(bounds)));
1151 }
1152}
1153
1154fn scale_vertical_mouse_autoscroll_delta(delta: f32) -> f32 {
1155 delta.powf(1.5) / 100.0
1156}
1157
1158fn scale_horizontal_mouse_autoscroll_delta(delta: f32) -> f32 {
1159 delta.powf(1.2) / 300.0
1160}
1161
1162#[cfg(test)]
1163mod tests {
1164 use super::*;
1165 use crate::{
1166 test::sample_text,
1167 {Editor, EditorSettings},
1168 };
1169 use language::Buffer;
1170
1171 #[gpui::test]
1172 fn test_layout_line_numbers(cx: &mut gpui::MutableAppContext) {
1173 let settings = EditorSettings::test(cx);
1174
1175 let buffer = cx.add_model(|cx| Buffer::new(0, sample_text(6, 6), cx));
1176 let (window_id, editor) = cx.add_window(Default::default(), |cx| {
1177 Editor::for_buffer(
1178 buffer,
1179 {
1180 let settings = settings.clone();
1181 move |_| settings.clone()
1182 },
1183 cx,
1184 )
1185 });
1186 let element = EditorElement::new(editor.downgrade(), settings);
1187
1188 let (layouts, _) = editor.update(cx, |editor, cx| {
1189 let snapshot = editor.snapshot(cx);
1190 let mut presenter = cx.build_presenter(window_id, 30.);
1191 let mut layout_cx = presenter.build_layout_context(false, cx);
1192 element.layout_rows(0..6, &Default::default(), &snapshot, &mut layout_cx)
1193 });
1194 assert_eq!(layouts.len(), 6);
1195 }
1196}