[gtk/wip/otte/boxes: 10/20] root: Add gtk_root_get_surface_transform()

[Benjamin Otte <otte src gnome org>]

commit 78889d5bb3127231b446000e98118fa941d7f484
Author: Benjamin Otte <otte redhat com>
Date:   Sat Feb 9 22:15:32 2019 +0100

    root: Add gtk_root_get_surface_transform()
    
    The function isn't used yet, so this is just infrastructure.

 gtk/gtkroot.c        | 25 +++++++++++++++++++++++++
 gtk/gtkroot.h        |  4 ++++
 gtk/gtkrootprivate.h |  3 +++
 gtk/gtkwindow.c      | 10 ++++++++++
 4 files changed, 42 insertions(+)
---
diff --git a/gtk/gtkroot.c b/gtk/gtkroot.c
index 23674e48a1..d94dd2e273 100644
--- a/gtk/gtkroot.c
+++ b/gtk/gtkroot.c
@@ -43,10 +43,20 @@ gtk_root_default_get_display (GtkRoot *self)
   return gdk_display_get_default ();
 }
 
+static void
+gtk_root_default_get_surface_transform (GtkRoot *self,
+                                        int     *x,
+                                        int     *y)
+{
+  *x = 0;
+  *y = 0;
+}
+
 static void
 gtk_root_default_init (GtkRootInterface *iface)
 {
   iface->get_display = gtk_root_default_get_display;
+  iface->get_surface_transform = gtk_root_default_get_surface_transform;
 }
 
 GdkDisplay *
@@ -60,3 +70,18 @@ gtk_root_get_display (GtkRoot *self)
   return iface->get_display (self);
 }
 
+
+void
+gtk_root_get_surface_transform (GtkRoot *self,
+                                int     *x,
+                                int     *y)
+{
+  GtkRootInterface *iface;
+
+  g_return_if_fail (GTK_IS_ROOT (self));
+  g_return_if_fail (x != 0);
+  g_return_if_fail (y != 0);
+
+  iface = GTK_ROOT_GET_IFACE (self);
+  return iface->get_surface_transform (self, x, y);
+}
diff --git a/gtk/gtkroot.h b/gtk/gtkroot.h
index e1d7ee670d..b0680462a5 100644
--- a/gtk/gtkroot.h
+++ b/gtk/gtkroot.h
@@ -46,6 +46,10 @@ struct _GtkRootInterface
 
   /*< public >*/
   GdkDisplay *          (* get_display)                 (GtkRoot                *self);
+
+  void                  (* get_surface_transform)       (GtkRoot                *root,
+                                                         int                    *x,
+                                                         int                    *y);
 };
 
 
diff --git a/gtk/gtkrootprivate.h b/gtk/gtkrootprivate.h
index 6d633cf2bc..964e832ba0 100644
--- a/gtk/gtkrootprivate.h
+++ b/gtk/gtkrootprivate.h
@@ -7,6 +7,9 @@ G_BEGIN_DECLS
 
 GdkDisplay *            gtk_root_get_display            (GtkRoot                *root);
 
+void                    gtk_root_get_surface_transform  (GtkRoot                *self,
+                                                         int                    *x,
+                                                         int                    *y);
 G_END_DECLS
 
 #endif /* __GTK_ROOT_PRIVATE_H__ */
diff --git a/gtk/gtkwindow.c b/gtk/gtkwindow.c
index 95b531ce40..98b6c237aa 100644
--- a/gtk/gtkwindow.c
+++ b/gtk/gtkwindow.c
@@ -2507,10 +2507,20 @@ gtk_window_root_get_display (GtkRoot *root)
   return priv->display;
 }
 
+static void
+gtk_window_root_get_surface_transform (GtkRoot *root,
+                                       int     *x,
+                                       int     *y)
+{
+  *x = 0;
+  *y = 0;
+}
+
 static void
 gtk_window_root_interface_init (GtkRootInterface *iface)
 {
   iface->get_display = gtk_window_root_get_display;
+  iface->get_surface_transform = gtk_window_root_get_surface_transform;
 }
 
 /**