wayland/actor-surface: Turn get_geometry_scale() into a vfunc

This allows us to implement more sophisticated logic for the different
cases. For DnD surfaces, use the geometry scale of the monitor where
the pointer is, instead of incorrectly assuming '1' as it was before.

https://gitlab.gnome.org/GNOME/mutter/merge_requests/780

src/wayland/meta-wayland-actor-surface.c

@@ -100,25 +100,10 @@ meta_wayland_actor_surface_queue_frame_callbacks (MetaWaylandActorSurface *actor
 double
 meta_wayland_actor_surface_get_geometry_scale (MetaWaylandActorSurface *actor_surface)
 {
-  MetaWaylandSurfaceRole *surface_role =
-    META_WAYLAND_SURFACE_ROLE (actor_surface);
-  MetaWaylandSurface *surface =
-    meta_wayland_surface_role_get_surface (surface_role);
-  MetaWindow *toplevel_window;
+  MetaWaylandActorSurfaceClass *actor_surface_class =
+    META_WAYLAND_ACTOR_SURFACE_GET_CLASS (actor_surface);
 
-  toplevel_window = meta_wayland_surface_get_toplevel_window (surface);
-  if (meta_is_stage_views_scaled ())
-    {
-      return 1;
-    }
-  else
-    {
-      if (!toplevel_window ||
-          toplevel_window->client_type == META_WINDOW_CLIENT_TYPE_X11)
-        return 1;
-      else
-        return meta_window_wayland_get_geometry_scale (toplevel_window);
-    }
+  return actor_surface_class->get_geometry_scale (actor_surface);
 }
 
 static void

src/wayland/meta-wayland-actor-surface.h

@@ -33,6 +33,7 @@ struct _MetaWaylandActorSurfaceClass
 {
   MetaWaylandSurfaceRoleClass parent_class;
 
+  double (* get_geometry_scale) (MetaWaylandActorSurface *actor_surface);
   void (* sync_actor_state) (MetaWaylandActorSurface *actor_surface);
 };
 

src/wayland/meta-wayland-dnd-surface.c

@@ -21,6 +21,7 @@
 
 #include "wayland/meta-wayland-dnd-surface.h"
 
+#include "backends/meta-logical-monitor.h"
 #include "compositor/meta-feedback-actor-private.h"
 
 struct _MetaWaylandSurfaceRoleDND
@@ -62,6 +63,38 @@ dnd_surface_commit (MetaWaylandSurfaceRole  *surface_role,
   surface_role_class->commit (surface_role, pending);
 }
 
+static MetaLogicalMonitor *
+dnd_surface_find_logical_monitor (MetaWaylandActorSurface *actor_surface)
+{
+  MetaBackend *backend = meta_get_backend ();
+  MetaCursorRenderer *cursor_renderer =
+    meta_backend_get_cursor_renderer (backend);
+  MetaMonitorManager *monitor_manager =
+     meta_backend_get_monitor_manager (backend);
+  ClutterPoint pointer_pos;
+
+  pointer_pos = meta_cursor_renderer_get_position (cursor_renderer);
+  return meta_monitor_manager_get_logical_monitor_at (monitor_manager,
+                                                      pointer_pos.x,
+                                                      pointer_pos.y);
+}
+
+static double
+dnd_subsurface_get_geometry_scale (MetaWaylandActorSurface *actor_surface)
+{
+  if (meta_is_stage_views_scaled ())
+    {
+      return 1;
+    }
+  else
+    {
+      MetaLogicalMonitor *logical_monitor;
+
+      logical_monitor = dnd_surface_find_logical_monitor (actor_surface);
+      return meta_logical_monitor_get_scale (logical_monitor);
+    }
+}
+
 static void
 dnd_subsurface_sync_actor_state (MetaWaylandActorSurface *actor_surface)
 {
@@ -116,5 +149,6 @@ meta_wayland_surface_role_dnd_class_init (MetaWaylandSurfaceRoleDNDClass *klass)
   surface_role_class->assigned = dnd_surface_assigned;
   surface_role_class->commit = dnd_surface_commit;
 
+  actor_surface_class->get_geometry_scale = dnd_subsurface_get_geometry_scale;
   actor_surface_class->sync_actor_state = dnd_subsurface_sync_actor_state;
 }

src/wayland/meta-wayland-shell-surface.c

@@ -180,6 +180,22 @@ meta_wayland_shell_surface_surface_commit (MetaWaylandSurfaceRole  *surface_role
     meta_wayland_surface_get_height (surface) * geometry_scale;
 }
 
+static double
+meta_wayland_shell_surface_get_geometry_scale (MetaWaylandActorSurface *actor_surface)
+{
+  MetaWaylandSurfaceRole *surface_role =
+    META_WAYLAND_SURFACE_ROLE (actor_surface);
+  MetaWaylandSurface *surface =
+    meta_wayland_surface_role_get_surface (surface_role);
+  MetaWindow *toplevel_window;
+
+  toplevel_window = meta_wayland_surface_get_toplevel_window (surface);
+  if (meta_is_stage_views_scaled () || !toplevel_window)
+    return 1;
+  else
+    return meta_window_wayland_get_geometry_scale (toplevel_window);
+}
+
 static void
 meta_wayland_shell_surface_sync_actor_state (MetaWaylandActorSurface *actor_surface)
 {
@@ -210,6 +226,9 @@ meta_wayland_shell_surface_class_init (MetaWaylandShellSurfaceClass *klass)
     META_WAYLAND_ACTOR_SURFACE_CLASS (klass);
 
   surface_role_class->commit = meta_wayland_shell_surface_surface_commit;
+
+  actor_surface_class->get_geometry_scale =
+    meta_wayland_shell_surface_get_geometry_scale;
   actor_surface_class->sync_actor_state =
     meta_wayland_shell_surface_sync_actor_state;
 }

src/wayland/meta-wayland-subsurface.c

@@ -240,6 +240,28 @@ meta_wayland_subsurface_get_toplevel (MetaWaylandSurfaceRole *surface_role)
     return NULL;
 }
 
+static double
+meta_wayland_subsurface_get_geometry_scale (MetaWaylandActorSurface *actor_surface)
+{
+  MetaWaylandSurfaceRole *surface_role =
+    META_WAYLAND_SURFACE_ROLE (actor_surface);
+  MetaWaylandSurface *surface =
+    meta_wayland_surface_role_get_surface (surface_role);
+  MetaWaylandSurface *parent = surface->sub.parent;
+
+  if (parent)
+    {
+      MetaWaylandActorSurface *parent_actor;
+
+      parent_actor = META_WAYLAND_ACTOR_SURFACE (surface->sub.parent->role);
+      return meta_wayland_actor_surface_get_geometry_scale (parent_actor);
+    }
+  else
+    {
+      return 1;
+    }
+}
+
 static void
 meta_wayland_subsurface_sync_actor_state (MetaWaylandActorSurface *actor_surface)
 {
@@ -273,6 +295,8 @@ meta_wayland_subsurface_class_init (MetaWaylandSubsurfaceClass *klass)
 
   surface_role_class->get_toplevel = meta_wayland_subsurface_get_toplevel;
 
+  actor_surface_class->get_geometry_scale =
+    meta_wayland_subsurface_get_geometry_scale;
   actor_surface_class->sync_actor_state =
     meta_wayland_subsurface_sync_actor_state;
 }

src/wayland/meta-xwayland.c

@@ -907,6 +907,12 @@ xwayland_surface_get_toplevel (MetaWaylandSurfaceRole *surface_role)
   return meta_wayland_surface_role_get_surface (surface_role);
 }
 
+static double
+xwayland_surface_get_geometry_scale (MetaWaylandActorSurface *actor_surface)
+{
+  return 1;
+}
+
 static void
 xwayland_surface_sync_actor_state (MetaWaylandActorSurface *actor_surface)
 {
@@ -938,6 +944,7 @@ meta_wayland_surface_role_xwayland_class_init (MetaWaylandSurfaceRoleXWaylandCla
   surface_role_class->commit = xwayland_surface_commit;
   surface_role_class->get_toplevel = xwayland_surface_get_toplevel;
 
+  actor_surface_class->get_geometry_scale = xwayland_surface_get_geometry_scale;
   actor_surface_class->sync_actor_state = xwayland_surface_sync_actor_state;
 
   xwayland_surface_signals[XWAYLAND_SURFACE_WINDOW_ASSOCIATED] =