[mutter] wayland/output: Rotate physical dimensions as well

[Jonas Ådahl <jadahl src gnome org>]

commit bda9c359af714cc465ef40bc9649b845ade80b7a
Author: Olivier Fourdan <ofourdan redhat com>
Date:   Wed Nov 7 10:13:24 2018 +0100

    wayland/output: Rotate physical dimensions as well
    
    For Wayland outputs, we do not expose the actual transformation because
    mutter does not support wl_surface.set_buffer_transform yet, instead we
    swap the logical width and height when the output is rotated.
    
    However, a client wishing to use the physical size would get confused,
    so if the output is rotated, rotate the physical dimensions as well for
    consistency.
    
    Closes: https://gitlab.gnome.org/GNOME/mutter/issues/369

 src/wayland/meta-wayland-outputs.c | 38 ++++++++++++++++++++++++++++++++++++--
 1 file changed, 36 insertions(+), 2 deletions(-)
---
diff --git a/src/wayland/meta-wayland-outputs.c b/src/wayland/meta-wayland-outputs.c
index e1e72814a..cb393ddf5 100644
--- a/src/wayland/meta-wayland-outputs.c
+++ b/src/wayland/meta-wayland-outputs.c
@@ -131,6 +131,39 @@ calculate_wayland_output_scale (MetaLogicalMonitor *logical_monitor)
   return ceilf (scale);
 }
 
+static void
+get_rotated_physical_dimensions (MetaMonitor *monitor,
+                                 int         *width_mm,
+                                 int         *height_mm)
+{
+  int monitor_width_mm, monitor_height_mm;
+  MetaLogicalMonitor *logical_monitor;
+
+  meta_monitor_get_physical_dimensions (monitor,
+                                        &monitor_width_mm,
+                                        &monitor_height_mm);
+  logical_monitor = meta_monitor_get_logical_monitor (monitor);
+
+  if (meta_monitor_transform_is_rotated (logical_monitor->transform))
+    {
+      *width_mm = monitor_height_mm;
+      *height_mm = monitor_width_mm;
+    }
+  else
+    {
+      *width_mm = monitor_width_mm;
+      *height_mm = monitor_height_mm;
+    }
+}
+
+static gboolean
+is_different_rotation (MetaLogicalMonitor *a,
+                       MetaLogicalMonitor *b)
+{
+  return (meta_monitor_transform_is_rotated (a->transform) !=
+          meta_monitor_transform_is_rotated (b->transform));
+}
+
 static void
 send_output_events (struct wl_resource *resource,
                     MetaWaylandOutput  *wayland_output,
@@ -163,7 +196,8 @@ send_output_events (struct wl_resource *resource,
 
   if (need_all_events ||
       old_logical_monitor->rect.x != logical_monitor->rect.x ||
-      old_logical_monitor->rect.y != logical_monitor->rect.y)
+      old_logical_monitor->rect.y != logical_monitor->rect.y ||
+      is_different_rotation (old_logical_monitor, logical_monitor))
     {
       int width_mm, height_mm;
       const char *vendor;
@@ -178,7 +212,7 @@ send_output_events (struct wl_resource *resource,
        * Arbitrarily use whatever monitor is the first in the logical monitor
        * and use that for these details.
        */
-      meta_monitor_get_physical_dimensions (monitor, &width_mm, &height_mm);
+      get_rotated_physical_dimensions (monitor, &width_mm, &height_mm);
       vendor = meta_monitor_get_vendor (monitor);
       product = meta_monitor_get_product (monitor);