clutter/actor: Add position argument to allocate_preferred_size()

Make clutter_actor_allocate_preferred_size() convenient to use from
layout managers by not "automatically" honouring the fixed position of
the actor, but instead allowing to pass a position to allocate the
actor at.

This way we can move the handling of fixed positions to
ClutterFixedLayout, the layout manager which is responsible for
allocating actors using fixed positions.

This also makes clutter_actor_allocate_preferred_size() more similar to
clutter_actor_allocate_available_size().

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1310

clutter/clutter/clutter-actor.c

@@ -14034,6 +14034,8 @@ clutter_actor_allocate_available_size (ClutterActor           *self,
 /**
  * clutter_actor_allocate_preferred_size:
  * @self: a #ClutterActor
+ * @x: the actor's X coordinate
+ * @y: the actor's Y coordinate
  *
  * Allocates the natural size of @self.
  *
@@ -14051,37 +14053,22 @@ clutter_actor_allocate_available_size (ClutterActor           *self,
  * Since: 0.8
  */
 void
-clutter_actor_allocate_preferred_size (ClutterActor *self)
+clutter_actor_allocate_preferred_size (ClutterActor *self,
+                                       float         x,
+                                       float         y)
 {
-  gfloat actor_x, actor_y;
   gfloat natural_width, natural_height;
   ClutterActorBox actor_box;
-  ClutterActorPrivate *priv;
-  const ClutterLayoutInfo *info;
 
   g_return_if_fail (CLUTTER_IS_ACTOR (self));
 
-  priv = self->priv;
-
-  if (priv->position_set)
-    {
-      info = _clutter_actor_get_layout_info_or_defaults (self);
-      actor_x = info->fixed_pos.x;
-      actor_y = info->fixed_pos.y;
-    }
-  else
-    {
-      actor_x = 0;
-      actor_y = 0;
-    }
-
   clutter_actor_get_preferred_size (self,
                                     NULL, NULL,
                                     &natural_width,
                                     &natural_height);
 
-  actor_box.x1 = actor_x;
+  actor_box.x1 = x;
-  actor_box.y1 = actor_y;
+  actor_box.y1 = y;
   actor_box.x2 = actor_box.x1 + natural_width;
   actor_box.y2 = actor_box.y1 + natural_height;
 

clutter/clutter/clutter-actor.h

@@ -419,7 +419,9 @@ CLUTTER_EXPORT
 void                            clutter_actor_allocate                          (ClutterActor                *self,
                                                                                  const ClutterActorBox       *box);
 CLUTTER_EXPORT
-void                            clutter_actor_allocate_preferred_size           (ClutterActor                *self);
+void                            clutter_actor_allocate_preferred_size           (ClutterActor                *self,
+                                                                                 float                        x,
+                                                                                 float                        y);
 CLUTTER_EXPORT
 void                            clutter_actor_allocate_available_size           (ClutterActor                *self,
                                                                                  gfloat                       x,

clutter/clutter/clutter-clone.c

@@ -245,7 +245,13 @@ clutter_clone_allocate (ClutterActor           *self,
    */
   if (clutter_actor_get_parent (priv->clone_source) != NULL &&
       !clutter_actor_has_allocation (priv->clone_source))
-    clutter_actor_allocate_preferred_size (priv->clone_source);
+    {
+      float x = 0.f;
+      float y = 0.f;
+
+      clutter_actor_get_fixed_position (priv->clone_source, &x, &y);
+      clutter_actor_allocate_preferred_size (priv->clone_source, x, y);
+    }
 
   clutter_actor_get_allocation_box (priv->clone_source, &source_box);
 

clutter/clutter/clutter-fixed-layout.c

@@ -139,7 +139,11 @@ clutter_fixed_layout_allocate (ClutterLayoutManager   *manager,
        child != NULL;
        child = clutter_actor_get_next_sibling (child))
     {
-      clutter_actor_allocate_preferred_size (child);
+      float x = 0.f;
+      float y = 0.f;
+
+      clutter_actor_get_fixed_position (child, &x, &y);
+      clutter_actor_allocate_preferred_size (child, x, y);
     }
 }
 

clutter/clutter/clutter-stage.c

@@ -1245,6 +1245,8 @@ clutter_stage_maybe_relayout (ClutterActor *actor)
   for (l = stolen_list; l; l = l->next)
     {
       g_autoptr (ClutterActor) queued_actor = l->data;
+      float x = 0.f;
+      float y = 0.f;
 
       if (CLUTTER_ACTOR_IN_RELAYOUT (queued_actor))  /* avoid reentrancy */
         continue;
@@ -1258,7 +1260,8 @@ clutter_stage_maybe_relayout (ClutterActor *actor)
 
       CLUTTER_SET_PRIVATE_FLAGS (queued_actor, CLUTTER_IN_RELAYOUT);
 
-      clutter_actor_allocate_preferred_size (queued_actor);
+      clutter_actor_get_fixed_position (queued_actor, &x, &y);
+      clutter_actor_allocate_preferred_size (queued_actor, x, y);
 
       CLUTTER_UNSET_PRIVATE_FLAGS (queued_actor, CLUTTER_IN_RELAYOUT);