#1547: keep the default board dots' size, and test the Preferences grid section

crates/ui-egui/src/board_ui_tests.rs

@@ -308,3 +308,32 @@ fn the_board_grid_follows_its_settings() {
     assert_eq!(grid_spacing(1e-320, 512.0, 2, 14.0), None, "no finite step that far out");
     assert!(grid_spacing(1e-300, 4.0, 12, 10.0).is_some_and(|(step, _)| step.is_finite()));
 }
+
+#[test]
+fn preferences_set_the_board_grid_and_the_default_dots_keep_their_size() {
+    let mut u = board();
+    let bg = egui::Color32::from_rgb(240, 240, 240);
+    // The default grid: dots a point and a half across at 100 %, one to three points on screen.
+    for (zoom, on_screen) in [(1.0, 1.5), (0.25, 1.0), (4.0, 3.0)] {
+        u.app.session.ds_mut().unwrap().view.zoom = zoom;
+        let t = crate::theme::Tokens::get(&u.ctx);
+        let size = crate::board_bar::dots(&u.app, bg, &t).unwrap().size;
+        assert!((size * zoom - on_screen).abs() < 1e-9, "at {zoom}: {size}");
+    }
+    u.app.session.ds_mut().unwrap().view.zoom = 1.0;
+    u.app.ui.preferences = true;
+    u.frame(vec![]);
+    let shapes = flat(&u.frame_output(vec![]).shapes);
+    assert!(has_text(&shapes, "Board grid") && has_text(&shapes, "Spacing"));
+    assert!(!has_text(&shapes, "Strong line every") && !has_text(&shapes, "Reset grid"), "dots, as usual");
+    click(&mut u, text_center(&shapes, "Graph paper"));
+    assert_eq!(u.app.session.prefs.board_grid.style, figcraft_engine::board_grid::GridStyle::Graph);
+    let shapes = flat(&u.frame_output(vec![]).shapes);
+    assert!(has_text(&shapes, "Strong line every"), "graph paper's cells per strong line");
+    click(&mut u, text_center(&shapes, "Reset grid"));
+    assert_eq!(u.app.session.prefs.board_grid, Default::default());
+    // No grid: nothing to set but the style.
+    u.app.run("board.grid", json!({"style": "none"}));
+    let shapes = flat(&u.frame_output(vec![]).shapes);
+    assert!(has_text(&shapes, "Board grid") && !has_text(&shapes, "Spacing"));
+}

crates/ui-egui/src/canvas/board_bar.rs

@@ -321,10 +321,10 @@ pub fn dots(app: &FigApp, bg: Color32, t: &Tokens) -> Option<figcraft_render::Do
     // Graph paper's in-between lines stay fainter than its strong ones even zoomed in.
     let faded = alpha * fade * if g.style == GridStyle::Graph { 0.5 } else { 1.0 };
     let color = |a: f32| figcraft_color::Color::from_rgba8(ink.r(), ink.g(), ink.b(), (a * 255.0).round() as u8);
-    // Dots grow a little zoomed in, and never shrink below their size at 100 % zoomed out (where
-    // a pixel-sized dot all but disappears).
+    // Dots are about a point and a half across on screen, growing a little zoomed in, scaled by
+    // the size setting (1, the default, keeps the usual dots).
     let k = g.size;
-    let size = if lines { k.max(0.5) / zoom } else { (1.5 * k * zoom.max(1.0).sqrt()).min(3.0 * k.max(1.0)) / zoom };
+    let size = if lines { k.max(0.5) / zoom } else { (1.5 * zoom.sqrt()).clamp(1.0, 3.0) * k / zoom };
     Some(figcraft_render::Dots { step, size, color: color(alpha), faded: color(faded), lines, major })
 }