| 1 | use super::*; |
| 2 | |
| 3 | /// What determines one rendered row's pixels: its cells, the cursor on it, the |
| 4 | /// selection span over it, and the blink phase. Two equal `RowSnap`s render |
| 5 | /// identically, so a buffer holding an equal snapshot needs no repaint. |
| 6 | #[derive(Clone, PartialEq, Debug)] |
| 7 | struct RowSnap { |
| 8 | cells: Vec<Cell>, |
| 9 | /// `(col, shape, focused)` when the cursor is drawn on this row. |
| 10 | cursor: Option<(usize, CursorShape, bool)>, |
| 11 | /// Inclusive selected column span on this row. |
| 12 | sel: Option<(usize, usize)>, |
| 13 | /// Search-match spans `(lo, hi, is_current)` highlighted on this row. |
| 14 | search: Vec<(usize, usize, bool)>, |
| 15 | /// Search-prompt text drawn over this row (only the bottom row, when active). |
| 16 | overlay: Option<String>, |
| 17 | /// IME preedit `(start_col, text)` drawn inline over this row (cursor row). |
| 18 | preedit: Option<(usize, String)>, |
| 19 | /// Blink phase, but only varied when the row actually has blinking ink, so |
| 20 | /// non-blinking rows stay equal across phase toggles. |
| 21 | blink: bool, |
| 22 | } |
| 23 | |
| 24 | /// One shm buffer plus the per-row snapshot of what it currently displays. |
| 25 | #[derive(Debug)] |
| 26 | pub(super) struct FrameBuf { |
| 27 | buffer: Buffer, |
| 28 | rows: Vec<RowSnap>, |
| 29 | } |
| 30 | |
| 31 | /// Snapshot the determinants of viewport row `y`'s pixels. |
| 32 | fn row_snap(grid: &Grid, y: usize, focused: bool, blink_on: bool) -> RowSnap { |
| 33 | let abs = grid.view_to_abs(y); |
| 34 | let cells = grid.view_row(y).to_vec(); |
| 35 | let cursor = if grid.view_at_bottom() && grid.cursor().1 == y { |
| 36 | let visible = grid.cursor_visible() && (!grid.cursor_blink() || blink_on); |
| 37 | visible.then(|| (grid.cursor().0, grid.cursor_shape(), focused)) |
| 38 | } else { |
| 39 | None |
| 40 | }; |
| 41 | let has_blink = cells |
| 42 | .iter() |
| 43 | .any(|c| c.flags.contains(crate::grid::Flags::BLINK)); |
| 44 | RowSnap { |
| 45 | cells, |
| 46 | cursor, |
| 47 | sel: grid.selection_span_on(abs), |
| 48 | search: grid.search_spans_on(abs), |
| 49 | overlay: None, |
| 50 | preedit: None, |
| 51 | blink: if has_blink { blink_on } else { true }, |
| 52 | } |
| 53 | } |
| 54 | impl App { |
| 55 | /// Render only the rows that changed since the chosen buffer last displayed |
| 56 | /// them, damage just those rows, and commit with a frame-callback request. |
| 57 | pub(super) fn present(&mut self) { |
| 58 | self.needs_draw = false; |
| 59 | // URL hint labels overlay the grid but are not part of the row snapshot, |
| 60 | // so force a full redraw while the labels are showing. |
| 61 | if self.url_mode { |
| 62 | self.frames.clear(); |
| 63 | } |
| 64 | // Render into a buffer sized in physical pixels (logical × scale); the |
| 65 | // viewport presents it back at the logical surface size. |
| 66 | let (w, h) = self.phys_dims(); |
| 67 | let m = self.renderer.metrics(); |
| 68 | let (focused, blink_on) = (self.focused, self.blink_on); |
| 69 | |
| 70 | // A resize invalidates every buffer's contents and size. |
| 71 | if self.buf_dims != (w, h) { |
| 72 | self.frames.clear(); |
| 73 | self.buf_dims = (w, h); |
| 74 | } |
| 75 | |
| 76 | let Some(session) = self.session.as_ref() else { |
| 77 | return; |
| 78 | }; |
| 79 | let grid = session.term.grid(); |
| 80 | // The visual bell inverts fg/bg for the duration of the flash. |
| 81 | let flashed = self.flashing.then(|| session.term.theme().inverted()); |
| 82 | let theme = flashed.as_ref().unwrap_or(session.term.theme()); |
| 83 | let rows = grid.rows(); |
| 84 | let mut cur: Vec<RowSnap> = (0..rows) |
| 85 | .map(|y| row_snap(grid, y, focused, blink_on)) |
| 86 | .collect(); |
| 87 | |
| 88 | // The search prompt occupies the bottom row while search mode is active. |
| 89 | // Recording it in the snapshot keeps the row's damage/diff correct. |
| 90 | let bar_text = self.searching.then(|| { |
| 91 | let (n, total) = grid.search_count(); |
| 92 | format!( |
| 93 | "search: {} [{n}/{total}]", |
| 94 | grid.search_query().unwrap_or("") |
| 95 | ) |
| 96 | }); |
| 97 | if let Some(text) = &bar_text |
| 98 | && rows > 0 |
| 99 | { |
| 100 | cur[rows - 1].overlay = Some(text.clone()); |
| 101 | } |
| 102 | |
| 103 | // The IME preedit is drawn inline at the cursor while composing. |
| 104 | if !self.preedit.is_empty() && grid.view_at_bottom() { |
| 105 | let (cx, cy) = grid.cursor(); |
| 106 | if cy < rows { |
| 107 | cur[cy].preedit = Some((cx, self.preedit.clone())); |
| 108 | } |
| 109 | } |
| 110 | |
| 111 | // Reuse a buffer the compositor has released, else grow the ring. |
| 112 | let stride = w as i32 * 4; |
| 113 | let mut idx = None; |
| 114 | for i in 0..self.frames.len() { |
| 115 | if self.pool.canvas(&self.frames[i].buffer).is_some() { |
| 116 | idx = Some(i); |
| 117 | break; |
| 118 | } |
| 119 | } |
| 120 | let idx = match idx { |
| 121 | Some(i) => i, |
| 122 | None if self.frames.len() < MAX_BUFFERS => { |
| 123 | match self |
| 124 | .pool |
| 125 | .create_buffer(w as i32, h as i32, stride, wl_shm::Format::Argb8888) |
| 126 | { |
| 127 | Ok((buffer, _)) => { |
| 128 | self.frames.push(FrameBuf { |
| 129 | buffer, |
| 130 | rows: Vec::new(), |
| 131 | }); |
| 132 | self.frames.len() - 1 |
| 133 | } |
| 134 | Err(err) => { |
| 135 | tracing::error!("allocate shm buffer: {err}"); |
| 136 | return; |
| 137 | } |
| 138 | } |
| 139 | } |
| 140 | // All buffers are still held by the compositor; a release event will |
| 141 | // wake us and `needs_draw` (re-set below) retries then. |
| 142 | None => { |
| 143 | self.needs_draw = true; |
| 144 | return; |
| 145 | } |
| 146 | }; |
| 147 | |
| 148 | // Rows that differ from what this buffer last showed (all, if fresh). |
| 149 | let prev = &self.frames[idx].rows; |
| 150 | let dirty: Vec<usize> = (0..rows) |
| 151 | .filter(|&y| prev.get(y) != Some(&cur[y])) |
| 152 | .collect(); |
| 153 | if dirty.is_empty() { |
| 154 | return; |
| 155 | } |
| 156 | |
| 157 | // A buffer used for the first time has uninitialized margins; paint the |
| 158 | // whole thing (background + padding) once, then damage it in full below. |
| 159 | let fresh = self.frames[idx].rows.is_empty(); |
| 160 | let pad_y = self.to_phys(self.config.main.pad_y) as i32; |
| 161 | let Some(canvas) = self.pool.canvas(&self.frames[idx].buffer) else { |
| 162 | return; |
| 163 | }; |
| 164 | let dims = (w as usize, h as usize); |
| 165 | let frame = crate::render::Frame { |
| 166 | theme, |
| 167 | focused, |
| 168 | blink_on, |
| 169 | hovered_link: self.hovered_link, |
| 170 | }; |
| 171 | if fresh { |
| 172 | self.renderer.clear(canvas, dims, theme); |
| 173 | } |
| 174 | for &y in &dirty { |
| 175 | self.renderer.render_row(canvas, dims, grid, &frame, y); |
| 176 | } |
| 177 | // Draw the search prompt over the (now repainted) bottom row. |
| 178 | if let Some(text) = &bar_text |
| 179 | && dirty.contains(&(rows - 1)) |
| 180 | { |
| 181 | self.renderer |
| 182 | .render_search_bar(canvas, dims, theme, rows - 1, text); |
| 183 | } |
| 184 | // Draw the IME preedit inline over its (repainted) cursor row. |
| 185 | for &y in &dirty { |
| 186 | if let Some((col, text)) = &cur[y].preedit { |
| 187 | self.renderer |
| 188 | .render_preedit(canvas, dims, theme, y, *col, text); |
| 189 | } |
| 190 | } |
| 191 | // Draw URL hint labels on top, narrowing to those matching the input. |
| 192 | if self.url_mode { |
| 193 | for (hit, label) in self.url_hits.iter().zip(&self.url_labels) { |
| 194 | if label.starts_with(&self.url_input) { |
| 195 | self.renderer |
| 196 | .render_label(canvas, dims, theme, hit.row, hit.col, label); |
| 197 | } |
| 198 | } |
| 199 | } |
| 200 | self.frames[idx].rows = cur; |
| 201 | |
| 202 | let surface = self.window.wl_surface(); |
| 203 | if let Err(err) = self.frames[idx].buffer.attach_to(surface) { |
| 204 | tracing::error!("attach buffer: {err}"); |
| 205 | return; |
| 206 | } |
| 207 | // With a viewport the buffer is presented at the logical destination, so |
| 208 | // its own scale stays 1; without one, fall back to integer buffer scale. |
| 209 | if let Some(vp) = &self.viewport { |
| 210 | surface.set_buffer_scale(1); |
| 211 | vp.set_destination(self.width.max(1) as i32, self.height.max(1) as i32); |
| 212 | } else { |
| 213 | surface.set_buffer_scale((self.scale120 / 120).max(1) as i32); |
| 214 | } |
| 215 | if fresh { |
| 216 | surface.damage_buffer(0, 0, w as i32, h as i32); |
| 217 | } else { |
| 218 | for &y in &dirty { |
| 219 | let top = pad_y + y as i32 * m.height as i32; |
| 220 | surface.damage_buffer(0, top, w as i32, m.height as i32); |
| 221 | } |
| 222 | } |
| 223 | surface.frame(&self.qh, surface.clone()); |
| 224 | self.window.commit(); |
| 225 | self.frame_pending = true; |
| 226 | } |
| 227 | } |