From 1d214956f99541a702bf1b07946cba252d1c56d3 Mon Sep 17 00:00:00 2001
From: dotCooCoo <RobertLeeLW@gmail.com>
Date: Sat, 17 Oct 2026 20:38:33 -0700
Subject: [PATCH] Smart Guides: object highlighting stays off with Snap to Grid
 or Pixel Preview

The reference app's help says Smart Guides cannot be used while Snap to
Grid or Pixel Preview is on, even with the menu command selected. The
Selection tool's move already leaves Smart Guides out under Snap to
Grid, but the canvas still drew the Object Highlighting outline under
the pointer with either view on.

The hover outline now draws only with Smart Guides and Object
Highlighting on and with Snap to Grid and Pixel Preview off.
---
 crates/ui-egui/src/canvas.rs | 35 +++++++++++++++++++++++++++++++++--
 1 file changed, 33 insertions(+), 2 deletions(-)

diff --git a/crates/ui-egui/src/canvas.rs b/crates/ui-egui/src/canvas.rs
index 84b46b637..145028320 100644
--- a/crates/ui-egui/src/canvas.rs
+++ b/crates/ui-egui/src/canvas.rs
@@ -1981,8 +1981,8 @@ fn panel_drop(app: &mut VectorcraftApp, ui: &Ui, resp: &egui::Response, xf: &Xf)
 
 fn hover_highlight(app: &VectorcraftApp, p: &egui::Painter, xf: &Xf) {
     let Some(h) = app.hover_doc else { return };
-    // Smart Guides › Object Highlighting: a Smart Guides display option, so it needs them on.
-    if !app.ui.view.smart_guides || !app.session.prefs.object_highlighting {
+    // Smart Guides › Object Highlighting: a Smart Guides display option, so it needs them on and Snap to Grid and Pixel Preview off.
+    if !app.ui.view.smart_guides || !app.session.prefs.object_highlighting || app.ui.view.snap_to_grid || app.ui.view.pixel_preview {
         return;
     }
     if app.session.tool_busy() || !matches!(app.session.tool_id(), "selection" | "directSelection" | "groupSelection") {
@@ -5274,6 +5274,37 @@ mod tests {
         assert_eq!(dots(&mut app).len(), 2, "one anchor still shows them");
     }
 
+    /// Smart Guides › Object Highlighting (#394): the outline of the object under the pointer does not
+    /// show with View › Snap to Grid or View › Pixel Preview on, even with Smart Guides and the option on.
+    #[test]
+    fn snap_to_grid_and_pixel_preview_hide_the_hover_outline() {
+        let mut app = VectorcraftApp::new(Session::new(), Default::default());
+        app.session.execute("file.new", &json!({"width": 400, "height": 300})).unwrap();
+        let id = app.session.execute("shape.rectangle", &json!({"x": 100, "y": 100, "width": 100, "height": 100})).unwrap()["id"].as_u64().unwrap();
+        app.session.execute("select.none", &json!({})).unwrap();
+        let ctx = egui::Context::default();
+        frame(&mut app, &ctx, vec![]);
+        let rect = app.canvas_rect.unwrap();
+        let over = Xf::new(rect, app.view().unwrap()).to_screen(Point::new(150.0, 150.0));
+        let layer = egui::epaint::ColorMode::Solid(c32(app.session.active().unwrap().doc.layer_color(vectorcraft_doc::NodeId(id))));
+        let outlines = |app: &mut VectorcraftApp| {
+            frame(app, &ctx, vec![egui::Event::PointerMoved(over)]);
+            shapes(app, &ctx).iter().filter(|s| matches!(s, Shape::Path(ps) if ps.stroke.width == 1.5 && ps.stroke.color == layer)).count()
+        };
+        assert!(app.ui.view.smart_guides && app.session.prefs.object_highlighting);
+        assert!(outlines(&mut app) > 0, "highlighted with Snap to Grid and Pixel Preview off");
+        app.run("view.snapToGrid", json!({})).unwrap();
+        assert!(app.ui.view.snap_to_grid);
+        assert_eq!(outlines(&mut app), 0, "Snap to Grid on");
+        app.run("view.snapToGrid", json!({})).unwrap();
+        assert!(outlines(&mut app) > 0, "Snap to Grid off again");
+        app.run("view.pixelPreview", json!({})).unwrap();
+        assert!(app.ui.view.pixel_preview);
+        assert_eq!(outlines(&mut app), 0, "Pixel Preview on");
+        app.run("view.pixelPreview", json!({})).unwrap();
+        assert!(outlines(&mut app) > 0, "Pixel Preview off again");
+    }
+
     /// Smart Guides › Object Highlighting (#394): the outline of the object under the pointer
     /// shows with Smart Guides on and the option on, and not otherwise.
     #[test]