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