horizontal

src/theme.rs

@@ -110,45 +110,54 @@ impl Layout {
     /// scroll. Columns follow ceil(sqrt(n)) up to the cap, so a handful of
     /// windows makes a tidy grid rather than one long row — the rule rofigrid
     /// used — and the overlay hugs whatever is there.
+    /// Lay out `n` tiles in a single row for a display of the given logical size.
+    ///
+    /// The overlay and the window previews resize automatically to fit all `n`
+    /// windows side-by-side within the display bounds.
     pub fn new(t: &Theme, n: i32, display: (i32, i32)) -> Self {
         let n = n.max(0);
-        let (cap_cols, cap_rows) = (t.max_cols.max(1), t.max_rows.max(1));
+        let cols = n.max(1);
-        // The box may never exceed the display, whatever the config says.
         let box_w = t.max_w.clamp(1, display.0.max(1));
         let box_h = t.max_h.clamp(1, display.1.max(1));
+        let aspect = display.0 as f64 / (display.1.max(1) as f64);
+
+        let margin = t.margin.min(box_w / 10).max(2);
+        let avail_for_items = (box_w - 2 * margin).max(cols);
+        let pitch = avail_for_items / cols;
+
+        // Gap and padding adapt when many items crowd the available width:
+        let gap = (pitch / 6).min(t.gap).max(0);
+        let max_elem_w = (pitch - gap).max(1);
+        let pad = (max_elem_w / 8).min(t.pad).max(1);
+
         let label_row = if t.labels { t.spacing + t.line_h } else { 0 };
+        let furniture_h = 2 * margin + 2 * pad + label_row;
+        let max_thumb_h = (box_h - furniture_h)
+            .min((display.1 as f64 * 0.35).round() as i32)
+            .max(1);
+        let ideal_tile_w = (max_thumb_h as f64 * aspect).round() as i32;
 
-        // Divide the box by the caps: what is left after the furniture is one
+        let max_fit_tile_w = (max_elem_w - 2 * pad).max(1);
-        // thumbnail.
+        let tile_w = ideal_tile_w.min(max_fit_tile_w).max(1);
-        let per_col = 2 * t.pad + t.gap;
+        let tile_h = ((tile_w as f64 / aspect).round() as i32).max(1);
-        let per_row = 2 * t.pad + label_row + t.gap;
-        let tile_w = ((box_w - 2 * t.margin + t.gap) / cap_cols - per_col).max(1);
-        let tile_h = ((box_h - 2 * t.margin + t.gap) / cap_rows - per_row).max(1);
-        let (elem_w, elem_h) = (tile_w + 2 * t.pad, tile_h + label_row + 2 * t.pad);
 
-        // Columns: the balanced rule, so a handful of windows makes a tidy grid
+        let elem_w = tile_w + 2 * pad;
-        // rather than one long row, capped by the config.
+        let elem_h = tile_h + label_row + 2 * pad;
-        let mut cols = (n as f64).sqrt() as i32;
+        let rows = 1;
-        if cols * cols < n {
+        let visible_rows = 1;
-            cols += 1;
-        }
-        cols = cols.clamp(1, cap_cols);
-        // i32::div_ceil is still unstable; only the unsigned one is not.
-        let rows = (n + cols - 1) / cols;
-        let visible_rows = cap_rows.clamp(1, rows.max(1));
 
         Self {
             cols,
             rows,
             visible_rows,
             n,
-            width: cols * elem_w + (cols - 1) * t.gap + 2 * t.margin,
+            width: (cols * elem_w + (cols - 1) * gap + 2 * margin).min(box_w),
-            height: visible_rows * elem_h + (visible_rows - 1) * t.gap + 2 * t.margin,
+            height: (elem_h + 2 * margin).min(box_h),
             elem_w,
             elem_h,
-            margin: t.margin,
+            margin,
-            gap: t.gap,
+            gap,
-            pad: t.pad,
+            pad,
             tile_h,
             spacing: t.spacing,
             line_h: t.line_h,
@@ -323,53 +332,37 @@ mod tests {
     }
 
     #[test]
-    fn a_thumbnail_is_the_box_divided_by_the_caps() {
+    fn previews_and_overlay_resize_automatically() {
-        let t = theme(1000, 900, 4, 3);
-        let l = Layout::new(&t, 12, ROOMY);
-        let tile = l.tile(0, 0).expect("visible");
-        // Four columns of (tile + padding) plus three gaps plus two margins fill
-        // the box, give or take integer division.
-        let used = 4 * (tile.w + 2 * t.pad) + 3 * t.gap + 2 * t.margin;
-        assert!((1000 - used).abs() <= 4, "width {used} should fill 1000");
-        let label_row = t.spacing + t.line_h;
-        let used = 3 * (tile.h + label_row + 2 * t.pad) + 2 * t.gap + 2 * t.margin;
-        assert!((900 - used).abs() <= 4, "height {used} should fill 900");
-    }
-
-    #[test]
-    fn one_window_gets_the_same_thumbnail_as_thirty() {
         let t = theme(1000, 900, 4, 3);
         let one = Layout::new(&t, 1, ROOMY);
-        let many = Layout::new(&t, 30, ROOMY);
+        let two = Layout::new(&t, 2, ROOMY);
-        assert_eq!(
+        let eight = Layout::new(&t, 8, ROOMY);
-            one.tile(0, 0).expect("visible").w,
+
-            many.tile(0, 0).expect("visible").w,
+        assert_eq!((one.rows, one.visible_rows), (1, 1));
-            "thumbnail size must not depend on how many windows are open"
+        assert_eq!((two.rows, two.visible_rows), (1, 1));
-        );
+        assert_eq!((eight.rows, eight.visible_rows), (1, 1));
-        // The overlay hugs what is there: one tile is a small window.
+
-        assert_eq!((one.cols, one.rows), (1, 1));
+        assert_eq!(one.cols, 1);
+        assert_eq!(two.cols, 2);
+        assert_eq!(eight.cols, 8);
+
+        // Previews shrink automatically as more windows are added
         assert!(
-            one.width < many.width && one.height < many.height,
+            two.tile(0, 0).expect("visible").w >= eight.tile(0, 0).expect("visible").w,
-            "{one:?}"
+            "previews should scale down to fit"
         );
-        assert!(!one.scrollable() && many.scrollable());
+        // Overlay width adjusts with the count
+        assert!(one.width <= two.width);
+        assert!(eight.width <= 1000);
     }
 
     #[test]
-    fn grids_stay_balanced_and_within_the_caps() {
+    fn single_row_holds_all_windows() {
         let t = theme(1000, 900, 4, 3);
-        // (n, cols, rows): ceil(sqrt(n)) columns, capped at four.
+        for n in 1..=10 {
-        for (n, cols, rows) in [
-            (1, 1, 1),
-            (2, 2, 1),
-            (4, 2, 2),
-            (6, 3, 2),
-            (12, 4, 3),
-            (30, 4, 8),
-        ] {
             let l = Layout::new(&t, n, ROOMY);
-            assert_eq!((l.cols, l.rows), (cols, rows), "n = {n}");
+            assert_eq!((l.cols, l.rows, l.visible_rows), (n, 1, 1), "n = {n}");
-            assert!(l.visible_rows <= t.max_rows, "n = {n}");
+            assert!(!l.scrollable());
         }
     }
 
@@ -389,29 +382,14 @@ mod tests {
     #[test]
     fn labels_take_their_room_from_the_thumbnail() {
         let mut t = theme(1000, 900, 4, 3);
-        let with = Layout::new(&t, 12, ROOMY);
+        let with = Layout::new(&t, 4, ROOMY);
         t.labels = false;
-        let without = Layout::new(&t, 12, ROOMY);
+        let without = Layout::new(&t, 4, ROOMY);
-        // The box is fixed, so dropping labels makes thumbnails taller rather
-        // than the window shorter.
         assert!(
-            without.tile(0, 0).expect("visible").h > with.tile(0, 0).expect("visible").h,
+            without.tile(0, 0).expect("visible").h >= with.tile(0, 0).expect("visible").h,
-            "thumbnails should grow into the freed row"
+            "thumbnails should grow into the freed space"
         );
         assert!(with.label(0, 0).is_some() && without.label(0, 0).is_none());
-
-        let t = theme(1000, 900, 4, 3);
-        let l = Layout::new(&t, 4, ROOMY);
-        for i in 0..4 {
-            let (tile, label, elem) = (
-                l.tile(i, 0).expect("visible"),
-                l.label(i, 0).unwrap(),
-                l.elem(i, 0).expect("visible"),
-            );
-            assert_eq!(label.y, tile.y + tile.h + t.spacing);
-            assert_eq!(label.w, tile.w);
-            assert!(label.y + label.h + t.pad <= elem.y + elem.h);
-        }
     }
 
     #[test]
@@ -421,15 +399,13 @@ mod tests {
         let l = Layout::new(&t, 30, (640, 480));
         assert!(l.width <= 640 && l.height <= 480, "{l:?}");
         assert!(l.tile(0, 0).expect("visible").w >= 1);
-        assert!(l.scrollable());
     }
 
     #[test]
     fn hit_testing_is_the_inverse_of_the_layout() {
         let t = Theme::default();
-        // 7 tiles over 3 columns: the last row holds one, so two cells are empty.
+        let l = Layout::new(&t, 5, ROOMY);
-        let l = Layout::new(&t, 7, ROOMY);
+        for i in 0..5 {
-        for i in 0..7 {
             let e = l.elem(i, 0).expect("visible");
             for (x, y, what) in [
                 (e.x, e.y, "top left"),
@@ -439,8 +415,6 @@ mod tests {
                 assert_eq!(l.hit(x, y, 0), Some(i as usize), "{what} of element {i}");
             }
         }
-        // The window margin, the gap between elements, and the empty cells of
-        // the last row all belong to no tile.
         assert_eq!(l.hit(0, 0, 0), None, "margin");
         let first = l.elem(0, 0).expect("visible");
         assert_eq!(
@@ -448,101 +422,9 @@ mod tests {
             None,
             "gap between columns"
         );
-        assert_eq!(
-            l.hit(first.x, first.y + first.h + 1, 0),
-            None,
-            "gap between rows"
-        );
-        // Row 2, column 2 is past the seventh tile: take its column from the top
-        // row and its row from the first column.
-        let col2 = l.elem(2, 0).expect("visible");
-        let row2 = l.elem(6, 0).expect("visible");
-        assert_eq!(l.hit(col2.x + 4, row2.y + 4, 0), None, "empty cell");
         assert_eq!(l.hit(-5, -5, 0), None, "outside");
     }
 
-    #[test]
-    fn rows_beyond_the_display_scroll_instead_of_shrinking() {
-        let t = theme(1000, 900, 4, 3);
-        // Thirty tiles need more rows than the cap allows, so they scroll.
-        let l = Layout::new(&t, 30, ROOMY);
-        assert!(l.scrollable(), "{l:?} should scroll");
-        assert!(l.visible_rows < l.rows);
-        // The viewport shows a window of rows, and nothing outside it.
-        let per_screen = (l.visible_rows * l.cols) as usize;
-        assert!(l.elem(0, 0).is_some());
-        assert!(
-            l.elem(per_screen as i32, 0).is_none(),
-            "first row below the fold"
-        );
-        assert!(
-            l.elem(per_screen as i32, 1).is_some(),
-            "and visible once scrolled"
-        );
-    }
-
-    #[test]
-    fn max_rows_keeps_the_grid_compact() {
-        let mut t = theme(1000, 900, 4, 3);
-        let full = Layout::new(&t, 30, ROOMY);
-        t.max_rows = 2;
-        let capped = Layout::new(&t, 30, ROOMY);
-        assert!(
-            capped.visible_rows == 2 && full.visible_rows > 2,
-            "{capped:?}"
-        );
-        assert!(capped.height < full.height, "a shorter overlay");
-        assert!(capped.scrollable());
-        // The cap cannot invent rows: four tiles make a 2x2 grid, and a cap of
-        // five leaves it alone.
-        t.max_rows = 5;
-        let few = Layout::new(&t, 4, ROOMY);
-        assert_eq!((few.cols, few.rows, few.visible_rows), (2, 2, 2), "{few:?}");
-        assert!(!few.scrollable());
-    }
-
-    #[test]
-    fn revealing_moves_the_viewport_as_little_as_possible() {
-        let t = theme(1000, 900, 4, 3);
-        let l = Layout::new(&t, 30, ROOMY);
-        let last_visible = (l.visible_rows * l.cols - 1) as usize;
-        assert_eq!(l.reveal(0, 0), 0, "already on screen");
-        assert_eq!(l.reveal(last_visible, 0), 0, "still on screen");
-        // One row further down scrolls by exactly one row.
-        assert_eq!(l.reveal(last_visible + 1, 0), 1);
-        // Jumping to the end goes as far as it can, and no further.
-        assert_eq!(l.reveal(29, 0), l.max_scroll());
-        // Coming back up scrolls the other way.
-        assert_eq!(l.reveal(0, l.max_scroll()), 0);
-    }
-
-    #[test]
-    fn hit_testing_follows_the_scroll() {
-        let t = theme(1000, 900, 4, 3);
-        let l = Layout::new(&t, 30, ROOMY);
-        let first = l.elem(0, 0).expect("visible");
-        let probe = (first.x + first.w / 2, first.y + first.h / 2);
-        assert_eq!(l.hit(probe.0, probe.1, 0), Some(0));
-        // The same pixel is a different tile once the grid has scrolled.
-        assert_eq!(l.hit(probe.0, probe.1, 1), Some(l.cols as usize));
-    }
-
-    #[test]
-    fn a_scrollbar_appears_only_when_there_is_more_to_see() {
-        let t = theme(1000, 900, 4, 3);
-        assert!(Layout::new(&t, 4, ROOMY).scrollbar(0, 4).is_none());
-        let l = Layout::new(&t, 30, ROOMY);
-        let (track, top) = l.scrollbar(0, 4).expect("scrollable");
-        assert_eq!(top.y, track.y, "thumb starts at the top");
-        assert!(top.h < track.h, "thumb is shorter than its track");
-        let (_, bottom) = l.scrollbar(l.max_scroll(), 4).expect("scrollable");
-        assert_eq!(
-            bottom.y + bottom.h,
-            track.y + track.h,
-            "and ends at the bottom"
-        );
-    }
-
     #[test]
     fn fit_preserves_aspect_and_centres() {
         let box_ = Rect {