From 17fdd3bb10e47183f6910c6d64cd15ad24f12454 Mon Sep 17 00:00:00 2001
From: Emil Ernerfeldt <emilernerfeldt@gmail.com>
Date: Sun, 31 Jan 2021 00:41:26 +0100
Subject: [PATCH] Label: draw underline and strikethrough on top of text

---
 egui/src/painter.rs       | 10 ++++++----
 egui/src/widgets/label.rs | 31 ++++++++++++++++++-------------
 2 files changed, 24 insertions(+), 17 deletions(-)

diff --git a/egui/src/painter.rs b/egui/src/painter.rs
index 14051a77..e6f368c1 100644
--- a/egui/src/painter.rs
+++ b/egui/src/painter.rs
@@ -117,10 +117,12 @@ impl Painter {
     }
 
     pub fn extend(&self, shapes: Vec<Shape>) {
-        self.ctx
-            .graphics()
-            .list(self.layer_id)
-            .extend(self.clip_rect, shapes);
+        if !shapes.is_empty() {
+            self.ctx
+                .graphics()
+                .list(self.layer_id)
+                .extend(self.clip_rect, shapes);
+        }
     }
 
     /// Modify an existing [`Shape`].
diff --git a/egui/src/widgets/label.rs b/egui/src/widgets/label.rs
index 0004af51..9d0092e3 100644
--- a/egui/src/widgets/label.rs
+++ b/egui/src/widgets/label.rs
@@ -168,33 +168,38 @@ impl Label {
             background_color = ui.style().visuals.code_bg_color;
         }
 
+        let mut lines = vec![];
+
         if strikethrough || underline || background_color != Color32::TRANSPARENT {
             for row in &galley.rows {
                 let rect = row.rect().translate(pos.to_vec2());
 
-                let stroke_width = 1.0;
-                if strikethrough {
-                    ui.painter().line_segment(
-                        [rect.left_center(), rect.right_center()],
-                        (stroke_width, text_color),
-                    );
-                }
-                if underline {
-                    ui.painter().line_segment(
-                        [rect.left_bottom(), rect.right_bottom()],
-                        (stroke_width, text_color),
-                    );
-                }
                 if background_color != Color32::TRANSPARENT {
                     let rect = rect.expand(1.0); // looks better
                     ui.painter().rect_filled(rect, 0.0, background_color);
                 }
+
+                let stroke_width = 1.0;
+                if strikethrough {
+                    lines.push(Shape::line_segment(
+                        [rect.left_center(), rect.right_center()],
+                        (stroke_width, text_color),
+                    ));
+                }
+                if underline {
+                    lines.push(Shape::line_segment(
+                        [rect.left_bottom(), rect.right_bottom()],
+                        (stroke_width, text_color),
+                    ));
+                }
             }
         }
 
         let text_style = self.text_style_or_default(ui.style());
         ui.painter()
             .galley_with_italics(pos, galley, text_style, text_color, italics);
+
+        ui.painter().extend(lines);
     }
 
     /// Read the text style, or get the default for the current style