From 0295d80f1a3a32783230e13d7709750bdb840ecf Mon Sep 17 00:00:00 2001
From: Teun van den Brand <tahvdbrand@gmail.com>
Date: Thu, 28 Mar 2024 16:51:34 +0100
Subject: [PATCH 1/2] `draw_key_polygon()` uses actual linewidth

---
 R/legend-draw.R | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/R/legend-draw.R b/R/legend-draw.R
index f1de0b80e5..9cb1b36e1a 100644
--- a/R/legend-draw.R
+++ b/R/legend-draw.R
@@ -74,9 +74,9 @@ draw_key_polygon <- function(data, params, size) {
     data$linewidth <- 0.5
   }
 
-  lwd <- min(data$linewidth, min(size) / 4)
+  lwd <- data$linewidth
 
-  rectGrob(
+  grob <- rectGrob(
     width = unit(1, "npc") - unit(lwd, "mm"),
     height = unit(1, "npc") - unit(lwd, "mm"),
     gp = gpar(
@@ -87,6 +87,12 @@ draw_key_polygon <- function(data, params, size) {
       linejoin = params$linejoin %||% "mitre",
       lineend = params$lineend %||% "butt"
   ))
+
+  # Magic number is 5 because we convert mm to cm (divide by 10) but we
+  # draw two lines in each direction (times 2)
+  attr(grob, "width")  <- lwd / 5
+  attr(grob, "height") <- lwd / 5
+  grob
 }
 
 #' @export

From 7b254b09b012d262f307d79915482fb489f03a67 Mon Sep 17 00:00:00 2001
From: Teun van den Brand <tahvdbrand@gmail.com>
Date: Thu, 28 Mar 2024 16:54:50 +0100
Subject: [PATCH 2/2] add news bullet

---
 NEWS.md | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/NEWS.md b/NEWS.md
index a96a2e4b02..b72a8ebc65 100644
--- a/NEWS.md
+++ b/NEWS.md
@@ -1,6 +1,8 @@
 
 # ggplot2 (development version)
 
+* The size of the `draw_key_polygon()` glyph now reflects the `linewidth` 
+  aesthetic (#4852).
 * `coord_map()` and `coord_polar()` throw informative warnings when used
   with the guide system (#5707).
 * When passing a function to `stat_contour(breaks)`, that function is used to