From 01f4e080df18bb083acae7fcd2f67e19858940fb Mon Sep 17 00:00:00 2001
From: Winston Chang <winston@stdout.org>
Date: Tue, 9 Apr 2013 15:57:18 -0500
Subject: [PATCH] Workaround for Cairo resolution bug

---
 R/imageutils.R | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/R/imageutils.R b/R/imageutils.R
index 55e715c9a..2803bd879 100644
--- a/R/imageutils.R
+++ b/R/imageutils.R
@@ -32,7 +32,14 @@ plotPNG <- function(func, filename=tempfile(fileext='.png'),
     pngfun <- png
   } else if (nchar(system.file(package = "Cairo"))) {
     require(Cairo)
-    pngfun <- CairoPNG
+
+    # Workaround for issue #140: Cairo ignores res and dpi settings. Need to
+    # use regular png function.
+    if (res == 72) {
+      pngfun <- CairoPNG
+    } else {
+      pngfun <- png
+    }
   } else {
     pngfun <- png
   }