compositor/dnd-actor: Take geometry scale into account on DnD-cancel

Technically this is still wrong if the source actor or dnd actor are
transformed in other ways. However geometry scale is the by far most
common case and we currently lack convenience API in Clutter to
easily compute the right values.

Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1683>

1 files changed, 16 insertions, 2 deletions

diff --git a/src/compositor/meta-dnd-actor.c b/src/compositor/meta-dnd-actor.c
index 31a01db90..80bffdeb7 100644
--- a/src/compositor/meta-dnd-actor.c
+++ b/src/compositor/meta-dnd-actor.c
@@ -28,6 +28,7 @@
 #include "config.h"
 
 #include "compositor/meta-dnd-actor-private.h"
+#include "compositor/meta-window-actor-private.h"
 
 #include "clutter/clutter.h"
 
@@ -206,16 +207,29 @@ meta_dnd_actor_drag_finish (MetaDnDActor *self,
 
       if (CLUTTER_ACTOR_IS_VISIBLE (self->drag_origin))
         {
+          MetaWindowActor *origin_actor;
           float anchor_x, anchor_y;
           graphene_point_t dest;
+          int origin_geometry_scale;
+          int feedback_geometry_scale;
 
           clutter_actor_get_transformed_position (self->drag_origin,
                                                   &dest.x, &dest.y);
+
+          origin_actor = meta_window_actor_from_actor (self->drag_origin);
+          g_return_if_fail (origin_actor);
+          origin_geometry_scale =
+            meta_window_actor_get_geometry_scale (origin_actor);
+
           meta_feedback_actor_get_anchor (META_FEEDBACK_ACTOR (self),
                                           &anchor_x, &anchor_y);
+          feedback_geometry_scale =
+            meta_feedback_actor_get_geometry_scale (META_FEEDBACK_ACTOR (self));
 
-          dest.x += self->drag_start_x - anchor_x;
-          dest.y += self->drag_start_y - anchor_y;
+          dest.x += ((self->drag_start_x * origin_geometry_scale) -
+                     (anchor_x * feedback_geometry_scale));
+          dest.y += ((self->drag_start_y * origin_geometry_scale) -
+                     (anchor_y * feedback_geometry_scale));
           clutter_actor_set_position (actor, dest.x, dest.y);
         }