terminal_element.rs

  1use editor::{Cursor, HighlightedRange, HighlightedRangeLine};
  2use gpui::{
  3    color::Color,
  4    elements::{Empty, Overlay},
  5    fonts::{HighlightStyle, Properties, Style::Italic, TextStyle, Underline, Weight},
  6    geometry::{
  7        rect::RectF,
  8        vector::{vec2f, Vector2F},
  9    },
 10    platform::{CursorStyle, MouseButton},
 11    serde_json::json,
 12    text_layout::{Line, RunStyle},
 13    AnyElement, Element, EventContext, FontCache, ModelContext, MouseRegion, Quad, SceneBuilder,
 14    SizeConstraint, TextLayoutCache, ViewContext, WeakModelHandle,
 15};
 16use itertools::Itertools;
 17use language::CursorShape;
 18use ordered_float::OrderedFloat;
 19use settings::Settings;
 20use terminal::{
 21    alacritty_terminal::{
 22        ansi::{Color as AnsiColor, Color::Named, CursorShape as AlacCursorShape, NamedColor},
 23        grid::Dimensions,
 24        index::Point,
 25        term::{cell::Flags, TermMode},
 26    },
 27    mappings::colors::convert_color,
 28    IndexedCell, Terminal, TerminalContent, TerminalSize,
 29};
 30use theme::TerminalStyle;
 31use util::ResultExt;
 32
 33use std::{fmt::Debug, ops::RangeInclusive};
 34use std::{mem, ops::Range};
 35
 36use crate::{DeployContextMenu, TerminalView};
 37
 38///The information generated during layout that is nescessary for painting
 39pub struct LayoutState {
 40    cells: Vec<LayoutCell>,
 41    rects: Vec<LayoutRect>,
 42    relative_highlighted_ranges: Vec<(RangeInclusive<Point>, Color)>,
 43    cursor: Option<Cursor>,
 44    background_color: Color,
 45    size: TerminalSize,
 46    mode: TermMode,
 47    display_offset: usize,
 48    hyperlink_tooltip: Option<AnyElement<TerminalView>>,
 49}
 50
 51///Helper struct for converting data between alacritty's cursor points, and displayed cursor points
 52struct DisplayCursor {
 53    line: i32,
 54    col: usize,
 55}
 56
 57impl DisplayCursor {
 58    fn from(cursor_point: Point, display_offset: usize) -> Self {
 59        Self {
 60            line: cursor_point.line.0 + display_offset as i32,
 61            col: cursor_point.column.0,
 62        }
 63    }
 64
 65    pub fn line(&self) -> i32 {
 66        self.line
 67    }
 68
 69    pub fn col(&self) -> usize {
 70        self.col
 71    }
 72}
 73
 74#[derive(Clone, Debug, Default)]
 75struct LayoutCell {
 76    point: Point<i32, i32>,
 77    text: Line,
 78}
 79
 80impl LayoutCell {
 81    fn new(point: Point<i32, i32>, text: Line) -> LayoutCell {
 82        LayoutCell { point, text }
 83    }
 84
 85    fn paint(
 86        &self,
 87        scene: &mut SceneBuilder,
 88        origin: Vector2F,
 89        layout: &LayoutState,
 90        visible_bounds: RectF,
 91        _view: &mut TerminalView,
 92        cx: &mut ViewContext<TerminalView>,
 93    ) {
 94        let pos = {
 95            let point = self.point;
 96            vec2f(
 97                (origin.x() + point.column as f32 * layout.size.cell_width).floor(),
 98                origin.y() + point.line as f32 * layout.size.line_height,
 99            )
100        };
101
102        self.text
103            .paint(scene, pos, visible_bounds, layout.size.line_height, cx);
104    }
105}
106
107#[derive(Clone, Debug, Default)]
108struct LayoutRect {
109    point: Point<i32, i32>,
110    num_of_cells: usize,
111    color: Color,
112}
113
114impl LayoutRect {
115    fn new(point: Point<i32, i32>, num_of_cells: usize, color: Color) -> LayoutRect {
116        LayoutRect {
117            point,
118            num_of_cells,
119            color,
120        }
121    }
122
123    fn extend(&self) -> Self {
124        LayoutRect {
125            point: self.point,
126            num_of_cells: self.num_of_cells + 1,
127            color: self.color,
128        }
129    }
130
131    fn paint(
132        &self,
133        scene: &mut SceneBuilder,
134        origin: Vector2F,
135        layout: &LayoutState,
136        _view: &mut TerminalView,
137        _cx: &mut ViewContext<TerminalView>,
138    ) {
139        let position = {
140            let point = self.point;
141            vec2f(
142                (origin.x() + point.column as f32 * layout.size.cell_width).floor(),
143                origin.y() + point.line as f32 * layout.size.line_height,
144            )
145        };
146        let size = vec2f(
147            (layout.size.cell_width * self.num_of_cells as f32).ceil(),
148            layout.size.line_height,
149        );
150
151        scene.push_quad(Quad {
152            bounds: RectF::new(position, size),
153            background: Some(self.color),
154            border: Default::default(),
155            corner_radius: 0.,
156        })
157    }
158}
159
160///The GPUI element that paints the terminal.
161///We need to keep a reference to the view for mouse events, do we need it for any other terminal stuff, or can we move that to connection?
162pub struct TerminalElement {
163    terminal: WeakModelHandle<Terminal>,
164    focused: bool,
165    cursor_visible: bool,
166}
167
168impl TerminalElement {
169    pub fn new(
170        terminal: WeakModelHandle<Terminal>,
171        focused: bool,
172        cursor_visible: bool,
173    ) -> TerminalElement {
174        TerminalElement {
175            terminal,
176            focused,
177            cursor_visible,
178        }
179    }
180
181    //Vec<Range<Point>> -> Clip out the parts of the ranges
182
183    fn layout_grid(
184        grid: &Vec<IndexedCell>,
185        text_style: &TextStyle,
186        terminal_theme: &TerminalStyle,
187        text_layout_cache: &TextLayoutCache,
188        font_cache: &FontCache,
189        hyperlink: Option<(HighlightStyle, &RangeInclusive<Point>)>,
190    ) -> (Vec<LayoutCell>, Vec<LayoutRect>) {
191        let mut cells = vec![];
192        let mut rects = vec![];
193
194        let mut cur_rect: Option<LayoutRect> = None;
195        let mut cur_alac_color = None;
196
197        let linegroups = grid.into_iter().group_by(|i| i.point.line);
198        for (line_index, (_, line)) in linegroups.into_iter().enumerate() {
199            for cell in line {
200                let mut fg = cell.fg;
201                let mut bg = cell.bg;
202                if cell.flags.contains(Flags::INVERSE) {
203                    mem::swap(&mut fg, &mut bg);
204                }
205
206                //Expand background rect range
207                {
208                    if matches!(bg, Named(NamedColor::Background)) {
209                        //Continue to next cell, resetting variables if nescessary
210                        cur_alac_color = None;
211                        if let Some(rect) = cur_rect {
212                            rects.push(rect);
213                            cur_rect = None
214                        }
215                    } else {
216                        match cur_alac_color {
217                            Some(cur_color) => {
218                                if bg == cur_color {
219                                    cur_rect = cur_rect.take().map(|rect| rect.extend());
220                                } else {
221                                    cur_alac_color = Some(bg);
222                                    if cur_rect.is_some() {
223                                        rects.push(cur_rect.take().unwrap());
224                                    }
225                                    cur_rect = Some(LayoutRect::new(
226                                        Point::new(line_index as i32, cell.point.column.0 as i32),
227                                        1,
228                                        convert_color(&bg, &terminal_theme),
229                                    ));
230                                }
231                            }
232                            None => {
233                                cur_alac_color = Some(bg);
234                                cur_rect = Some(LayoutRect::new(
235                                    Point::new(line_index as i32, cell.point.column.0 as i32),
236                                    1,
237                                    convert_color(&bg, &terminal_theme),
238                                ));
239                            }
240                        }
241                    }
242                }
243
244                //Layout current cell text
245                {
246                    let cell_text = &cell.c.to_string();
247                    if !is_blank(&cell) {
248                        let cell_style = TerminalElement::cell_style(
249                            &cell,
250                            fg,
251                            terminal_theme,
252                            text_style,
253                            font_cache,
254                            hyperlink,
255                        );
256
257                        let layout_cell = text_layout_cache.layout_str(
258                            cell_text,
259                            text_style.font_size,
260                            &[(cell_text.len(), cell_style)],
261                        );
262
263                        cells.push(LayoutCell::new(
264                            Point::new(line_index as i32, cell.point.column.0 as i32),
265                            layout_cell,
266                        ))
267                    };
268                }
269            }
270
271            if cur_rect.is_some() {
272                rects.push(cur_rect.take().unwrap());
273            }
274        }
275        (cells, rects)
276    }
277
278    // Compute the cursor position and expected block width, may return a zero width if x_for_index returns
279    // the same position for sequential indexes. Use em_width instead
280    fn shape_cursor(
281        cursor_point: DisplayCursor,
282        size: TerminalSize,
283        text_fragment: &Line,
284    ) -> Option<(Vector2F, f32)> {
285        if cursor_point.line() < size.total_lines() as i32 {
286            let cursor_width = if text_fragment.width() == 0. {
287                size.cell_width()
288            } else {
289                text_fragment.width()
290            };
291
292            //Cursor should always surround as much of the text as possible,
293            //hence when on pixel boundaries round the origin down and the width up
294            Some((
295                vec2f(
296                    (cursor_point.col() as f32 * size.cell_width()).floor(),
297                    (cursor_point.line() as f32 * size.line_height()).floor(),
298                ),
299                cursor_width.ceil(),
300            ))
301        } else {
302            None
303        }
304    }
305
306    ///Convert the Alacritty cell styles to GPUI text styles and background color
307    fn cell_style(
308        indexed: &IndexedCell,
309        fg: terminal::alacritty_terminal::ansi::Color,
310        style: &TerminalStyle,
311        text_style: &TextStyle,
312        font_cache: &FontCache,
313        hyperlink: Option<(HighlightStyle, &RangeInclusive<Point>)>,
314    ) -> RunStyle {
315        let flags = indexed.cell.flags;
316        let fg = convert_color(&fg, &style);
317
318        let mut underline = flags
319            .intersects(Flags::ALL_UNDERLINES)
320            .then(|| Underline {
321                color: Some(fg),
322                squiggly: flags.contains(Flags::UNDERCURL),
323                thickness: OrderedFloat(1.),
324            })
325            .unwrap_or_default();
326
327        if indexed.cell.hyperlink().is_some() {
328            if underline.thickness == OrderedFloat(0.) {
329                underline.thickness = OrderedFloat(1.);
330            }
331        }
332
333        let mut properties = Properties::new();
334        if indexed.flags.intersects(Flags::BOLD | Flags::DIM_BOLD) {
335            properties = *properties.weight(Weight::BOLD);
336        }
337        if indexed.flags.intersects(Flags::ITALIC) {
338            properties = *properties.style(Italic);
339        }
340
341        let font_id = font_cache
342            .select_font(text_style.font_family_id, &properties)
343            .unwrap_or(text_style.font_id);
344
345        let mut result = RunStyle {
346            color: fg,
347            font_id,
348            underline,
349        };
350
351        if let Some((style, range)) = hyperlink {
352            if range.contains(&indexed.point) {
353                if let Some(underline) = style.underline {
354                    result.underline = underline;
355                }
356
357                if let Some(color) = style.color {
358                    result.color = color;
359                }
360            }
361        }
362
363        result
364    }
365
366    fn generic_button_handler<E>(
367        connection: WeakModelHandle<Terminal>,
368        origin: Vector2F,
369        f: impl Fn(&mut Terminal, Vector2F, E, &mut ModelContext<Terminal>),
370    ) -> impl Fn(E, &mut TerminalView, &mut EventContext<TerminalView>) {
371        move |event, _: &mut TerminalView, cx| {
372            cx.focus_parent_view();
373            if let Some(conn_handle) = connection.upgrade(cx) {
374                conn_handle.update(cx, |terminal, cx| {
375                    f(terminal, origin, event, cx);
376
377                    cx.notify();
378                })
379            }
380        }
381    }
382
383    fn attach_mouse_handlers(
384        &self,
385        scene: &mut SceneBuilder,
386        origin: Vector2F,
387        visible_bounds: RectF,
388        mode: TermMode,
389        cx: &mut ViewContext<TerminalView>,
390    ) {
391        let connection = self.terminal;
392
393        let mut region = MouseRegion::new::<Self>(cx.view_id(), 0, visible_bounds);
394
395        // Terminal Emulator controlled behavior:
396        region = region
397            // Start selections
398            .on_down(
399                MouseButton::Left,
400                TerminalElement::generic_button_handler(
401                    connection,
402                    origin,
403                    move |terminal, origin, e, _cx| {
404                        terminal.mouse_down(&e, origin);
405                    },
406                ),
407            )
408            // Update drag selections
409            .on_drag(MouseButton::Left, move |event, _: &mut TerminalView, cx| {
410                if cx.is_parent_view_focused() {
411                    if let Some(conn_handle) = connection.upgrade(cx) {
412                        conn_handle.update(cx, |terminal, cx| {
413                            terminal.mouse_drag(event, origin);
414                            cx.notify();
415                        })
416                    }
417                }
418            })
419            // Copy on up behavior
420            .on_up(
421                MouseButton::Left,
422                TerminalElement::generic_button_handler(
423                    connection,
424                    origin,
425                    move |terminal, origin, e, cx| {
426                        terminal.mouse_up(&e, origin, cx);
427                    },
428                ),
429            )
430            // Context menu
431            .on_click(MouseButton::Right, move |e, _: &mut TerminalView, cx| {
432                let mouse_mode = if let Some(conn_handle) = connection.upgrade(cx) {
433                    conn_handle.update(cx, |terminal, _cx| terminal.mouse_mode(e.shift))
434                } else {
435                    // If we can't get the model handle, probably can't deploy the context menu
436                    true
437                };
438                if !mouse_mode {
439                    cx.dispatch_action(DeployContextMenu {
440                        position: e.position,
441                    });
442                }
443            })
444            .on_move(move |event, _: &mut TerminalView, cx| {
445                if cx.is_parent_view_focused() {
446                    if let Some(conn_handle) = connection.upgrade(cx) {
447                        conn_handle.update(cx, |terminal, cx| {
448                            terminal.mouse_move(&event, origin);
449                            cx.notify();
450                        })
451                    }
452                }
453            })
454            .on_scroll(move |event, _: &mut TerminalView, cx| {
455                if let Some(conn_handle) = connection.upgrade(cx) {
456                    conn_handle.update(cx, |terminal, cx| {
457                        terminal.scroll_wheel(event, origin);
458                        cx.notify();
459                    })
460                }
461            });
462
463        // Mouse mode handlers:
464        // All mouse modes need the extra click handlers
465        if mode.intersects(TermMode::MOUSE_MODE) {
466            region = region
467                .on_down(
468                    MouseButton::Right,
469                    TerminalElement::generic_button_handler(
470                        connection,
471                        origin,
472                        move |terminal, origin, e, _cx| {
473                            terminal.mouse_down(&e, origin);
474                        },
475                    ),
476                )
477                .on_down(
478                    MouseButton::Middle,
479                    TerminalElement::generic_button_handler(
480                        connection,
481                        origin,
482                        move |terminal, origin, e, _cx| {
483                            terminal.mouse_down(&e, origin);
484                        },
485                    ),
486                )
487                .on_up(
488                    MouseButton::Right,
489                    TerminalElement::generic_button_handler(
490                        connection,
491                        origin,
492                        move |terminal, origin, e, cx| {
493                            terminal.mouse_up(&e, origin, cx);
494                        },
495                    ),
496                )
497                .on_up(
498                    MouseButton::Middle,
499                    TerminalElement::generic_button_handler(
500                        connection,
501                        origin,
502                        move |terminal, origin, e, cx| {
503                            terminal.mouse_up(&e, origin, cx);
504                        },
505                    ),
506                )
507        }
508
509        scene.push_mouse_region(region);
510    }
511
512    ///Configures a text style from the current settings.
513    pub fn make_text_style(font_cache: &FontCache, settings: &Settings) -> TextStyle {
514        let font_family_name = settings
515            .terminal_overrides
516            .font_family
517            .as_ref()
518            .or(settings.terminal_defaults.font_family.as_ref())
519            .unwrap_or(&settings.buffer_font_family_name);
520        let font_features = settings
521            .terminal_overrides
522            .font_features
523            .as_ref()
524            .or(settings.terminal_defaults.font_features.as_ref())
525            .unwrap_or(&settings.buffer_font_features);
526
527        let family_id = font_cache
528            .load_family(&[font_family_name], &font_features)
529            .log_err()
530            .unwrap_or(settings.buffer_font_family);
531
532        let font_size = settings
533            .terminal_overrides
534            .font_size
535            .or(settings.terminal_defaults.font_size)
536            .unwrap_or(settings.buffer_font_size);
537
538        let font_id = font_cache
539            .select_font(family_id, &Default::default())
540            .unwrap();
541
542        TextStyle {
543            color: settings.theme.editor.text_color,
544            font_family_id: family_id,
545            font_family_name: font_cache.family_name(family_id).unwrap(),
546            font_id,
547            font_size,
548            font_properties: Default::default(),
549            underline: Default::default(),
550        }
551    }
552}
553
554impl Element<TerminalView> for TerminalElement {
555    type LayoutState = LayoutState;
556    type PaintState = ();
557
558    fn layout(
559        &mut self,
560        constraint: gpui::SizeConstraint,
561        view: &mut TerminalView,
562        cx: &mut ViewContext<TerminalView>,
563    ) -> (gpui::geometry::vector::Vector2F, Self::LayoutState) {
564        let settings = cx.global::<Settings>();
565        let font_cache = cx.font_cache();
566
567        //Setup layout information
568        let terminal_theme = settings.theme.terminal.clone(); //TODO: Try to minimize this clone.
569        let link_style = settings.theme.editor.link_definition;
570        let tooltip_style = settings.theme.tooltip.clone();
571
572        let text_style = TerminalElement::make_text_style(font_cache, settings);
573        let selection_color = settings.theme.editor.selection.selection;
574        let match_color = settings.theme.search.match_background;
575        let dimensions = {
576            let line_height = text_style.font_size * settings.terminal_line_height();
577            let cell_width = font_cache.em_advance(text_style.font_id, text_style.font_size);
578            TerminalSize::new(line_height, cell_width, constraint.max)
579        };
580
581        let search_matches = if let Some(terminal_model) = self.terminal.upgrade(cx) {
582            terminal_model.read(cx).matches.clone()
583        } else {
584            Default::default()
585        };
586
587        let background_color = terminal_theme.background;
588        let terminal_handle = self.terminal.upgrade(cx).unwrap();
589
590        let last_hovered_hyperlink = terminal_handle.update(cx, |terminal, cx| {
591            terminal.set_size(dimensions);
592            terminal.try_sync(cx);
593            terminal.last_content.last_hovered_hyperlink.clone()
594        });
595
596        let hyperlink_tooltip = last_hovered_hyperlink.map(|(uri, _, id)| {
597            let mut tooltip = Overlay::new(
598                Empty::new()
599                    .contained()
600                    .constrained()
601                    .with_width(dimensions.width())
602                    .with_height(dimensions.height())
603                    .with_tooltip::<TerminalElement>(id, uri, None, tooltip_style, cx),
604            )
605            .with_position_mode(gpui::elements::OverlayPositionMode::Local)
606            .into_any();
607
608            tooltip.layout(
609                SizeConstraint::new(Vector2F::zero(), cx.window_size()),
610                view,
611                cx,
612            );
613            tooltip
614        });
615
616        let TerminalContent {
617            cells,
618            mode,
619            display_offset,
620            cursor_char,
621            selection,
622            cursor,
623            last_hovered_hyperlink,
624            ..
625        } = { &terminal_handle.read(cx).last_content };
626
627        // searches, highlights to a single range representations
628        let mut relative_highlighted_ranges = Vec::new();
629        for search_match in search_matches {
630            relative_highlighted_ranges.push((search_match, match_color))
631        }
632        if let Some(selection) = selection {
633            relative_highlighted_ranges.push((selection.start..=selection.end, selection_color));
634        }
635
636        // then have that representation be converted to the appropriate highlight data structure
637
638        let (cells, rects) = TerminalElement::layout_grid(
639            cells,
640            &text_style,
641            &terminal_theme,
642            cx.text_layout_cache(),
643            cx.font_cache(),
644            last_hovered_hyperlink
645                .as_ref()
646                .map(|(_, range, _)| (link_style, range)),
647        );
648
649        //Layout cursor. Rectangle is used for IME, so we should lay it out even
650        //if we don't end up showing it.
651        let cursor = if let AlacCursorShape::Hidden = cursor.shape {
652            None
653        } else {
654            let cursor_point = DisplayCursor::from(cursor.point, *display_offset);
655            let cursor_text = {
656                let str_trxt = cursor_char.to_string();
657
658                let color = if self.focused {
659                    terminal_theme.background
660                } else {
661                    terminal_theme.foreground
662                };
663
664                cx.text_layout_cache().layout_str(
665                    &str_trxt,
666                    text_style.font_size,
667                    &[(
668                        str_trxt.len(),
669                        RunStyle {
670                            font_id: text_style.font_id,
671                            color,
672                            underline: Default::default(),
673                        },
674                    )],
675                )
676            };
677
678            let focused = self.focused;
679            TerminalElement::shape_cursor(cursor_point, dimensions, &cursor_text).map(
680                move |(cursor_position, block_width)| {
681                    let (shape, text) = match cursor.shape {
682                        AlacCursorShape::Block if !focused => (CursorShape::Hollow, None),
683                        AlacCursorShape::Block => (CursorShape::Block, Some(cursor_text)),
684                        AlacCursorShape::Underline => (CursorShape::Underscore, None),
685                        AlacCursorShape::Beam => (CursorShape::Bar, None),
686                        AlacCursorShape::HollowBlock => (CursorShape::Hollow, None),
687                        //This case is handled in the if wrapping the whole cursor layout
688                        AlacCursorShape::Hidden => unreachable!(),
689                    };
690
691                    Cursor::new(
692                        cursor_position,
693                        block_width,
694                        dimensions.line_height,
695                        terminal_theme.cursor,
696                        shape,
697                        text,
698                    )
699                },
700            )
701        };
702
703        //Done!
704        (
705            constraint.max,
706            LayoutState {
707                cells,
708                cursor,
709                background_color,
710                size: dimensions,
711                rects,
712                relative_highlighted_ranges,
713                mode: *mode,
714                display_offset: *display_offset,
715                hyperlink_tooltip,
716            },
717        )
718    }
719
720    fn paint(
721        &mut self,
722        scene: &mut SceneBuilder,
723        bounds: RectF,
724        visible_bounds: RectF,
725        layout: &mut Self::LayoutState,
726        view: &mut TerminalView,
727        cx: &mut ViewContext<TerminalView>,
728    ) -> Self::PaintState {
729        let visible_bounds = bounds.intersection(visible_bounds).unwrap_or_default();
730
731        //Setup element stuff
732        let clip_bounds = Some(visible_bounds);
733
734        scene.paint_layer(clip_bounds, |scene| {
735            let origin = bounds.origin() + vec2f(layout.size.cell_width, 0.);
736
737            // Elements are ephemeral, only at paint time do we know what could be clicked by a mouse
738            self.attach_mouse_handlers(scene, origin, visible_bounds, layout.mode, cx);
739
740            scene.push_cursor_region(gpui::CursorRegion {
741                bounds,
742                style: if layout.hyperlink_tooltip.is_some() {
743                    CursorStyle::PointingHand
744                } else {
745                    CursorStyle::IBeam
746                },
747            });
748
749            scene.paint_layer(clip_bounds, |scene| {
750                //Start with a background color
751                scene.push_quad(Quad {
752                    bounds: RectF::new(bounds.origin(), bounds.size()),
753                    background: Some(layout.background_color),
754                    border: Default::default(),
755                    corner_radius: 0.,
756                });
757
758                for rect in &layout.rects {
759                    rect.paint(scene, origin, layout, view, cx)
760                }
761            });
762
763            //Draw Highlighted Backgrounds
764            scene.paint_layer(clip_bounds, |scene| {
765                for (relative_highlighted_range, color) in layout.relative_highlighted_ranges.iter()
766                {
767                    if let Some((start_y, highlighted_range_lines)) =
768                        to_highlighted_range_lines(relative_highlighted_range, layout, origin)
769                    {
770                        let hr = HighlightedRange {
771                            start_y, //Need to change this
772                            line_height: layout.size.line_height,
773                            lines: highlighted_range_lines,
774                            color: color.clone(),
775                            //Copied from editor. TODO: move to theme or something
776                            corner_radius: 0.15 * layout.size.line_height,
777                        };
778                        hr.paint(bounds, scene);
779                    }
780                }
781            });
782
783            //Draw the text cells
784            scene.paint_layer(clip_bounds, |scene| {
785                for cell in &layout.cells {
786                    cell.paint(scene, origin, layout, visible_bounds, view, cx);
787                }
788            });
789
790            //Draw cursor
791            if self.cursor_visible {
792                if let Some(cursor) = &layout.cursor {
793                    scene.paint_layer(clip_bounds, |scene| {
794                        cursor.paint(scene, origin, cx);
795                    })
796                }
797            }
798
799            if let Some(element) = &mut layout.hyperlink_tooltip {
800                element.paint(scene, origin, visible_bounds, view, cx)
801            }
802        });
803    }
804
805    fn metadata(&self) -> Option<&dyn std::any::Any> {
806        None
807    }
808
809    fn debug(
810        &self,
811        _: RectF,
812        _: &Self::LayoutState,
813        _: &Self::PaintState,
814        _: &TerminalView,
815        _: &gpui::ViewContext<TerminalView>,
816    ) -> gpui::serde_json::Value {
817        json!({
818            "type": "TerminalElement",
819        })
820    }
821
822    fn rect_for_text_range(
823        &self,
824        _: Range<usize>,
825        bounds: RectF,
826        _: RectF,
827        layout: &Self::LayoutState,
828        _: &Self::PaintState,
829        _: &TerminalView,
830        _: &gpui::ViewContext<TerminalView>,
831    ) -> Option<RectF> {
832        // Use the same origin that's passed to `Cursor::paint` in the paint
833        // method bove.
834        let mut origin = bounds.origin() + vec2f(layout.size.cell_width, 0.);
835
836        // TODO - Why is it necessary to move downward one line to get correct
837        // positioning? I would think that we'd want the same rect that is
838        // painted for the cursor.
839        origin += vec2f(0., layout.size.line_height);
840
841        Some(layout.cursor.as_ref()?.bounding_rect(origin))
842    }
843}
844
845fn is_blank(cell: &IndexedCell) -> bool {
846    if cell.c != ' ' {
847        return false;
848    }
849
850    if cell.bg != AnsiColor::Named(NamedColor::Background) {
851        return false;
852    }
853
854    if cell.hyperlink().is_some() {
855        return false;
856    }
857
858    if cell
859        .flags
860        .intersects(Flags::ALL_UNDERLINES | Flags::INVERSE | Flags::STRIKEOUT)
861    {
862        return false;
863    }
864
865    return true;
866}
867
868fn to_highlighted_range_lines(
869    range: &RangeInclusive<Point>,
870    layout: &LayoutState,
871    origin: Vector2F,
872) -> Option<(f32, Vec<HighlightedRangeLine>)> {
873    // Step 1. Normalize the points to be viewport relative.
874    // When display_offset = 1, here's how the grid is arranged:
875    //-2,0 -2,1...
876    //--- Viewport top
877    //-1,0 -1,1...
878    //--------- Terminal Top
879    // 0,0  0,1...
880    // 1,0  1,1...
881    //--- Viewport Bottom
882    // 2,0  2,1...
883    //--------- Terminal Bottom
884
885    // Normalize to viewport relative, from terminal relative.
886    // lines are i32s, which are negative above the top left corner of the terminal
887    // If the user has scrolled, we use the display_offset to tell us which offset
888    // of the grid data we should be looking at. But for the rendering step, we don't
889    // want negatives. We want things relative to the 'viewport' (the area of the grid
890    // which is currently shown according to the display offset)
891    let unclamped_start = Point::new(
892        range.start().line + layout.display_offset,
893        range.start().column,
894    );
895    let unclamped_end = Point::new(range.end().line + layout.display_offset, range.end().column);
896
897    // Step 2. Clamp range to viewport, and return None if it doesn't overlap
898    if unclamped_end.line.0 < 0 || unclamped_start.line.0 > layout.size.num_lines() as i32 {
899        return None;
900    }
901
902    let clamped_start_line = unclamped_start.line.0.max(0) as usize;
903    let clamped_end_line = unclamped_end.line.0.min(layout.size.num_lines() as i32) as usize;
904    //Convert the start of the range to pixels
905    let start_y = origin.y() + clamped_start_line as f32 * layout.size.line_height;
906
907    // Step 3. Expand ranges that cross lines into a collection of single-line ranges.
908    //  (also convert to pixels)
909    let mut highlighted_range_lines = Vec::new();
910    for line in clamped_start_line..=clamped_end_line {
911        let mut line_start = 0;
912        let mut line_end = layout.size.columns();
913
914        if line == clamped_start_line {
915            line_start = unclamped_start.column.0 as usize;
916        }
917        if line == clamped_end_line {
918            line_end = unclamped_end.column.0 as usize + 1; //+1 for inclusive
919        }
920
921        highlighted_range_lines.push(HighlightedRangeLine {
922            start_x: origin.x() + line_start as f32 * layout.size.cell_width,
923            end_x: origin.x() + line_end as f32 * layout.size.cell_width,
924        });
925    }
926
927    Some((start_y, highlighted_range_lines))
928}