From d47434bdb6da8df2603e6a23859a9d73c7e1f760 Mon Sep 17 00:00:00 2001
From: Matthias Clasen <mclasen@redhat.com>
Date: Wed, 29 May 2019 18:11:57 +0000
Subject: [PATCH] Mention global coordinates in the migration guide

---
 docs/reference/gtk/migrating-3to4.xml | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/docs/reference/gtk/migrating-3to4.xml b/docs/reference/gtk/migrating-3to4.xml
index a1d9dd08b5..1e3a9079eb 100644
--- a/docs/reference/gtk/migrating-3to4.xml
+++ b/docs/reference/gtk/migrating-3to4.xml
@@ -314,8 +314,15 @@
         doubles, and the _double variants have been removed. Update your
         code accordingly.
       </para>
+      <para>
+        Any APIs that deal with global (or root) coordinates have been
+        removed in GTK4, since not all backends support them. You should
+        replace your use of such APIs with surface-relative equivalents.
+        Examples of this are gdk_surfae_get_origin(), gdk_surface_move()
+        or gdk_event_get_root_coords().
+      </para>
     </section>
-
+ 
     <section>
       <title>Adapt to GdkKeymap API changes</title>
       <para>
-- 
2.30.2