surface: Add coordinate translation

We maintain offsets for popups, so we can translate
coordinates between surfaces that are attached directly
or indirectly to the same toplevel. Add an api for that.

diff --git a/gdk/gdksurface.c b/gdk/gdksurface.c
index b3f0c64223b3244e88a57edb79c3fd8bb06e29b2..fc30d532d986629d6eaf6e50a4664d28f243ac28 100644 (file)
--- a/gdk/gdksurface.c
+++ b/gdk/gdksurface.c
@@ -4076,3 +4076,41 @@ gdk_surface_handle_event (GdkEvent *event)
 
   return handled;
 }
+
+gboolean
+gdk_surface_translate_coordinates (GdkSurface *from,
+                                   GdkSurface *to,
+                                   double     *x,
+                                   double     *y)
+{
+  int x1, y1, x2, y2;
+  GdkSurface *f, *t;
+
+  x1 = 0;
+  y1 = 0;
+  f = from;
+  while (f->parent)
+    {
+      x1 += f->x;
+      y1 += f->y;
+      f = f->parent;
+    }
+
+  x2 = 0;
+  y2 = 0;
+  t = to;
+  while (t->parent)
+    {
+      x2 += t->x;
+      y2 += t->y;
+      t = t->parent;
+    }
+
+  if (f != t)
+    return FALSE;
+
+  *x += x1 - x2;
+  *y += y1 - y2;
+
+  return TRUE;
+}

diff --git a/gdk/gdksurface.h b/gdk/gdksurface.h
index b02d40192a785ded4b68db68000befce5805431b..acca090683029915f73445d3259753879af3f8a3 100644 (file)
--- a/gdk/gdksurface.h
+++ b/gdk/gdksurface.h
@@ -557,6 +557,12 @@ gint          gdk_surface_get_origin     (GdkSurface      *surface,
                                           gint            *x,
                                           gint            *y);
 GDK_AVAILABLE_IN_ALL
+gboolean gdk_surface_translate_coordinates (GdkSurface *from,
+                                            GdkSurface *to,
+                                            double     *x,
+                                            double     *y);
+
+GDK_AVAILABLE_IN_ALL
 void          gdk_surface_get_frame_extents (GdkSurface     *surface,
                                              GdkRectangle  *rect);