[mutter] wayland/surface: Move relative coordinate calculating to roles

[Robert Mader <rmader src gnome org>]

commit 54194e67e3fe29b60df97817a4843d6a2ee138ed
Author: Jonas Ådahl <jadahl gmail com>
Date:   Wed Oct 9 09:47:23 2019 +0200

    wayland/surface: Move relative coordinate calculating to roles
    
    The role determines how a relative coordinate is calculated. More
    specifically, using clutters API to transform coordinates is only
    accurate right after a clutter layout pass but this function is used
    e.g. to deliver pointer motion events which can happen at any time. This
    isn't a problem for Wayland clients since they don't control their
    position, but X clients do and we'd be sending outdated coordinates if a
    client is moving a window in response to motion events.
    
    This was already done already, but now move the Xwayland specific logic
    to the Xwayland surface role, keeping the generic transformation logic
    in the generic actor surface role.
    
    https://gitlab.gnome.org/GNOME/mutter/merge_requests/835

 src/wayland/meta-wayland-actor-surface.c | 19 +++++++++++++++++++
 src/wayland/meta-wayland-surface.c       | 31 +++++--------------------------
 src/wayland/meta-wayland-surface.h       |  5 +++++
 src/wayland/meta-xwayland-surface.c      | 19 +++++++++++++++++++
 4 files changed, 48 insertions(+), 26 deletions(-)
---
diff --git a/src/wayland/meta-wayland-actor-surface.c b/src/wayland/meta-wayland-actor-surface.c
index efccede83..d61603905 100644
--- a/src/wayland/meta-wayland-actor-surface.c
+++ b/src/wayland/meta-wayland-actor-surface.c
@@ -325,6 +325,23 @@ meta_wayland_actor_surface_is_on_logical_monitor (MetaWaylandSurfaceRole *surfac
   return is_on_monitor;
 }
 
+static void
+meta_wayland_actor_surface_get_relative_coordinates (MetaWaylandSurfaceRole *surface_role,
+                                                     float                   abs_x,
+                                                     float                   abs_y,
+                                                     float                  *out_sx,
+                                                     float                  *out_sy)
+{
+  MetaWaylandActorSurface *actor_surface =
+    META_WAYLAND_ACTOR_SURFACE (surface_role);
+  MetaWaylandActorSurfacePrivate *priv =
+    meta_wayland_actor_surface_get_instance_private (actor_surface);
+
+  clutter_actor_transform_stage_point (CLUTTER_ACTOR (priv->actor),
+                                       abs_x, abs_y,
+                                       out_sx, out_sy);
+}
+
 static void
 meta_wayland_actor_surface_init (MetaWaylandActorSurface *actor_surface)
 {
@@ -348,6 +365,8 @@ meta_wayland_actor_surface_class_init (MetaWaylandActorSurfaceClass *klass)
   surface_role_class->apply_state = meta_wayland_actor_surface_apply_state;
   surface_role_class->is_on_logical_monitor =
     meta_wayland_actor_surface_is_on_logical_monitor;
+  surface_role_class->get_relative_coordinates =
+    meta_wayland_actor_surface_get_relative_coordinates;
 
   klass->sync_actor_state = meta_wayland_actor_surface_real_sync_actor_state;
 }
diff --git a/src/wayland/meta-wayland-surface.c b/src/wayland/meta-wayland-surface.c
index a17431853..d94e5b63a 100644
--- a/src/wayland/meta-wayland-surface.c
+++ b/src/wayland/meta-wayland-surface.c
@@ -1592,33 +1592,12 @@ meta_wayland_surface_get_relative_coordinates (MetaWaylandSurface *surface,
                                                float               *sx,
                                                float               *sy)
 {
-  MetaWindow *window;
-
-  /* Using clutter API to transform coordinates is only accurate right
-   * after a clutter layout pass but this function is used e.g. to
-   * deliver pointer motion events which can happen at any time. This
-   * isn't a problem for wayland clients since they don't control
-   * their position, but X clients do and we'd be sending outdated
-   * coordinates if a client is moving a window in response to motion
-   * events.
-   */
-  window = meta_wayland_surface_get_window (surface);
-  if (window &&
-      window->client_type == META_WINDOW_CLIENT_TYPE_X11)
-    {
-      MetaRectangle window_rect;
-
-      meta_window_get_buffer_rect (window, &window_rect);
-      *sx = abs_x - window_rect.x;
-      *sy = abs_y - window_rect.y;
-    }
-  else
-    {
-      ClutterActor *actor =
-        CLUTTER_ACTOR (meta_wayland_surface_get_actor (surface));
+  MetaWaylandSurfaceRoleClass *surface_role_class =
+    META_WAYLAND_SURFACE_ROLE_GET_CLASS (surface->role);
 
-      clutter_actor_transform_stage_point (actor, abs_x, abs_y, sx, sy);
-    }
+  surface_role_class->get_relative_coordinates (surface->role,
+                                                abs_x, abs_y,
+                                                sx, sy);
 }
 
 void
diff --git a/src/wayland/meta-wayland-surface.h b/src/wayland/meta-wayland-surface.h
index 5477eb99e..7420274d4 100644
--- a/src/wayland/meta-wayland-surface.h
+++ b/src/wayland/meta-wayland-surface.h
@@ -63,6 +63,11 @@ struct _MetaWaylandSurfaceRoleClass
   MetaWaylandSurface * (*get_toplevel) (MetaWaylandSurfaceRole *surface_role);
   gboolean (*should_cache_state) (MetaWaylandSurfaceRole *surface_role);
   void (*notify_subsurface_state_changed) (MetaWaylandSurfaceRole *surface_role);
+  void (*get_relative_coordinates) (MetaWaylandSurfaceRole *surface_role,
+                                    float                   abs_x,
+                                    float                   abs_y,
+                                    float                  *out_sx,
+                                    float                  *out_sy);
 };
 
 struct _MetaWaylandSurfaceState
diff --git a/src/wayland/meta-xwayland-surface.c b/src/wayland/meta-xwayland-surface.c
index b1894ef8c..905b49afd 100644
--- a/src/wayland/meta-xwayland-surface.c
+++ b/src/wayland/meta-xwayland-surface.c
@@ -80,6 +80,23 @@ meta_xwayland_surface_associate_with_window (MetaXwaylandSurface *xwayland_surfa
     }
 }
 
+static void
+meta_xwayland_surface_get_relative_coordinates (MetaWaylandSurfaceRole *surface_role,
+                                                float                   abs_x,
+                                                float                   abs_y,
+                                                float                  *out_sx,
+                                                float                  *out_sy)
+{
+  MetaWaylandSurface *surface =
+    meta_wayland_surface_role_get_surface (surface_role);
+  MetaRectangle window_rect;
+
+  meta_window_get_buffer_rect (meta_wayland_surface_get_window (surface),
+                               &window_rect);
+  *out_sx = abs_x - window_rect.x;
+  *out_sy = abs_y - window_rect.y;
+}
+
 static MetaWaylandSurface *
 meta_xwayland_surface_get_toplevel (MetaWaylandSurfaceRole *surface_role)
 {
@@ -143,6 +160,8 @@ meta_xwayland_surface_class_init (MetaXwaylandSurfaceClass *klass)
 
   object_class->finalize = meta_xwayland_surface_finalize;
 
+  surface_role_class->get_relative_coordinates =
+    meta_xwayland_surface_get_relative_coordinates;
   surface_role_class->get_toplevel = meta_xwayland_surface_get_toplevel;
 
   actor_surface_class->get_geometry_scale =