[Emacs-diffs] emacs-26 2892f05 1/2: Scale monitor dimensions obtained from GTK

[Martin Rudalics]

branch: emacs-26
commit 2892f05792e1f52b0966f92c5ed1aa75dcdd66a3
Author: Robert Pluim <address@hidden>
Commit: Martin Rudalics <address@hidden>

    Scale monitor dimensions obtained from GTK
    
    This is part one of a two part fix for the GTK scaling
    problems.  See the thread starting at
    http://lists.gnu.org/archive/html/emacs-devel/2018-01/msg00372.html
    for an explanation of why it has been added to Emacs 26.
    
    * src/xfns.c (Fx_display_monitor_attributes_list): Take scaling factor
    into account when using GTK to query the monitor dimensions, which
    allows frameset-restore to position frames correctly.
---
 src/xfns.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/src/xfns.c b/src/xfns.c
index dd3b36c..4ea5113 100644
--- a/src/xfns.c
+++ b/src/xfns.c
@@ -4940,6 +4940,7 @@ Internal use only, use `display-monitor-attributes-list' 
instead.  */)
       gint width_mm = -1, height_mm = -1;
       GdkRectangle rec, work;
       struct MonitorInfo *mi = &monitors[i];
+      int scale;
 
 #if GTK_CHECK_VERSION (3, 22, 0)
       GdkMonitor *monitor = gdk_display_get_monitor (gdpy, i);
@@ -4985,6 +4986,16 @@ Internal use only, use `display-monitor-attributes-list' 
instead.  */)
       }
 #endif
 
+      /* GTK returns scaled sizes for the workareas.  */
+#if GTK_CHECK_VERSION (3, 22, 0)
+      scale = gdk_monitor_get_scale_factor (monitor);
+#else
+      scale = gdk_screen_get_monitor_scale_factor (gscreen, i);
+#endif
+      rec.width *= scale;
+      rec.height *= scale;
+      work.width *= scale;
+      work.height *= scale;
 
       mi->geom.x = rec.x;
       mi->geom.y = rec.y;