Desktop: Snap overlays to physical instead of logical pixels (#3493)

WIP

editor/src/messages/portfolio/document/overlays/utility_types_native.rs

@@ -491,11 +491,13 @@ impl OverlayContextInternal {
 
 		let mut path = BezPath::new();
 		if let Some(first) = polygon.last() {
-			path.move_to(kurbo::Point::new(first.x.round() - 0.5, first.y.round() - 0.5));
+			let p = self.snap_to_physical_pixel_center(*first);
+			path.move_to(kurbo::Point::new(p.x, p.y));
 		}
 
 		for point in polygon {
-			path.line_to(kurbo::Point::new(point.x.round() - 0.5, point.y.round() - 0.5));
+			let p = self.snap_to_physical_pixel_center(*point);
+			path.line_to(kurbo::Point::new(p.x, p.y));
 		}
 		path.close_path();
 
@@ -522,8 +524,8 @@ impl OverlayContextInternal {
 	fn dashed_line(&mut self, start: DVec2, end: DVec2, color: Option<&str>, thickness: Option<f64>, dash_width: Option<f64>, dash_gap_width: Option<f64>, dash_offset: Option<f64>) {
 		let transform = self.get_transform();
 
-		let start = start.round() - DVec2::splat(0.5);
+		let start = self.snap_to_physical_pixel_center(start);
-		let end = end.round() - DVec2::splat(0.5);
+		let end = self.snap_to_physical_pixel_center(end);
 
 		let mut path = BezPath::new();
 		path.move_to(kurbo::Point::new(start.x, start.y));
@@ -541,7 +543,7 @@ impl OverlayContextInternal {
 
 	fn manipulator_handle(&mut self, position: DVec2, selected: bool, color: Option<&str>) {
 		let transform = self.get_transform();
-		let position = position.round() - DVec2::splat(0.5);
+		let position = self.snap_to_physical_pixel_center(position);
 
 		let circle = kurbo::Circle::new((position.x, position.y), MANIPULATOR_GROUP_MARKER_SIZE / 2.);
 
@@ -554,8 +556,7 @@ impl OverlayContextInternal {
 
 	fn hover_manipulator_handle(&mut self, position: DVec2, selected: bool) {
 		let transform = self.get_transform();
-
+		let position = self.snap_to_physical_pixel_center(position);
-		let position = position.round() - DVec2::splat(0.5);
 
 		let circle = kurbo::Circle::new((position.x, position.y), (MANIPULATOR_GROUP_MARKER_SIZE + 2.) / 2.);
 
@@ -605,7 +606,7 @@ impl OverlayContextInternal {
 		let color_fill = color_fill.unwrap_or(COLOR_OVERLAY_WHITE);
 		let color_stroke = color_stroke.unwrap_or(COLOR_OVERLAY_BLUE);
 
-		let position = position.round() - DVec2::splat(0.5);
+		let position = self.snap_to_physical_pixel_center(position);
 		let corner = position - DVec2::splat(size) / 2.;
 
 		let transform = self.get_transform();
@@ -620,7 +621,7 @@ impl OverlayContextInternal {
 		let size = 1.;
 		let color_fill = color.unwrap_or(COLOR_OVERLAY_WHITE);
 
-		let position = position.round() - DVec2::splat(0.5);
+		let position = self.snap_to_physical_pixel_center(position);
 		let corner = position - DVec2::splat(size) / 2.;
 
 		let transform = self.get_transform();
@@ -632,7 +633,7 @@ impl OverlayContextInternal {
 	fn circle(&mut self, position: DVec2, radius: f64, color_fill: Option<&str>, color_stroke: Option<&str>) {
 		let color_fill = color_fill.unwrap_or(COLOR_OVERLAY_WHITE);
 		let color_stroke = color_stroke.unwrap_or(COLOR_OVERLAY_BLUE);
-		let position = position.round();
+		let position = self.snap_to_physical_pixel(position);
 
 		let transform = self.get_transform();
 		let circle = kurbo::Circle::new((position.x, position.y), radius);
@@ -708,7 +709,7 @@ impl OverlayContextInternal {
 		self.draw_arc(pivot, arc_radius, offset_angle, (angle) % TAU + offset_angle);
 	}
 
-	fn draw_scale(&mut self, start: DVec2, scale: f64, radius: f64, text: &str) {
+	pub fn draw_scale(&mut self, start: DVec2, scale: f64, radius: f64, text: &str) {
 		let sign = scale.signum();
 		let mut fill_color = Color::from_rgb_str(COLOR_OVERLAY_WHITE.strip_prefix('#').unwrap()).unwrap().with_alpha(0.05).to_rgba_hex_srgb();
 		fill_color.insert(0, '#');
@@ -739,7 +740,7 @@ impl OverlayContextInternal {
 		let Some(show_hover_ring) = show_compass_with_hover_ring else { return };
 
 		let transform = self.get_transform();
-		let center = compass_center.round() - DVec2::splat(0.5);
+		let center = self.snap_to_physical_pixel_center(compass_center);
 
 		// Hover ring
 		if show_hover_ring {
@@ -784,7 +785,7 @@ impl OverlayContextInternal {
 
 	fn pivot(&mut self, position: DVec2, angle: f64) {
 		let uv = DVec2::from_angle(angle);
-		let (x, y) = (position.round() - DVec2::splat(0.5)).into();
+		let (x, y) = self.snap_to_physical_pixel_center(position).into();
 
 		let transform = self.get_transform();
 
@@ -814,7 +815,7 @@ impl OverlayContextInternal {
 	}
 
 	fn dowel_pin(&mut self, position: DVec2, angle: f64, color: Option<&str>) {
-		let (x, y) = (position.round() - DVec2::splat(0.5)).into();
+		let (x, y) = self.snap_to_physical_pixel_center(position).into();
 		let color = color.unwrap_or(COLOR_OVERLAY_YELLOW_DULL);
 
 		let transform = self.get_transform();
@@ -921,29 +922,30 @@ impl OverlayContextInternal {
 			};
 
 			let start_point = transform.transform_point2(point_to_dvec2(first.start()));
+			let start_point = self.snap_to_physical_pixel(start_point);
 			path.move_to(kurbo::Point::new(start_point.x, start_point.y));
 
 			for curve in curves {
 				match curve {
 					PathSeg::Line(line) => {
 						let a = transform.transform_point2(point_to_dvec2(line.p1));
-						let a = a.round() - DVec2::splat(0.5);
+						let a = self.snap_to_physical_pixel_center(a);
 						path.line_to(kurbo::Point::new(a.x, a.y));
 					}
 					PathSeg::Quad(quad_bez) => {
 						let a = transform.transform_point2(point_to_dvec2(quad_bez.p1));
 						let b = transform.transform_point2(point_to_dvec2(quad_bez.p2));
-						let a = a.round() - DVec2::splat(0.5);
+						let a = self.snap_to_physical_pixel_center(a);
-						let b = b.round() - DVec2::splat(0.5);
+						let b = self.snap_to_physical_pixel_center(b);
 						path.quad_to(kurbo::Point::new(a.x, a.y), kurbo::Point::new(b.x, b.y));
 					}
 					PathSeg::Cubic(cubic_bez) => {
 						let a = transform.transform_point2(point_to_dvec2(cubic_bez.p1));
 						let b = transform.transform_point2(point_to_dvec2(cubic_bez.p2));
 						let c = transform.transform_point2(point_to_dvec2(cubic_bez.p3));
-						let a = a.round() - DVec2::splat(0.5);
+						let a = self.snap_to_physical_pixel_center(a);
-						let b = b.round() - DVec2::splat(0.5);
+						let b = self.snap_to_physical_pixel_center(b);
-						let c = c.round() - DVec2::splat(0.5);
+						let c = self.snap_to_physical_pixel_center(c);
 						path.curve_to(kurbo::Point::new(a.x, a.y), kurbo::Point::new(b.x, b.y), kurbo::Point::new(c.x, c.y));
 					}
 				}
@@ -1145,4 +1147,20 @@ impl OverlayContextInternal {
 			self.line(quad.bottom_left(), quad.bottom_right(), None, None);
 		}
 	}
+
+	fn snap_to_physical_pixel(&self, p: DVec2) -> DVec2 {
+		let s = self.viewport.scale();
+		if !s.is_finite() || s <= 0.0 {
+			return p.round();
+		}
+		(p * s).round() / s
+	}
+
+	fn snap_to_physical_pixel_center(&self, p: DVec2) -> DVec2 {
+		let s = self.viewport.scale();
+		if !s.is_finite() || s <= 0.0 {
+			return p.round() - DVec2::splat(0.5);
+		}
+		self.snap_to_physical_pixel(p) - DVec2::splat(0.5 / s)
+	}
 }