diff --git a/gdk/gdkdraw.c b/gdk/gdkdraw.c
index 7885ab5211..3305e49ca8 100644
--- a/gdk/gdkdraw.c
+++ b/gdk/gdkdraw.c
@@ -184,13 +184,10 @@ gdk_draw_point (GdkDrawable *drawable,
                 gint         x,
                 gint         y)
 {
-  GdkGCPrivate *gc_private;
   GdkPoint point;
 
   g_return_if_fail (GDK_IS_DRAWABLE (drawable));
-  g_return_if_fail (gc != NULL);
-
-  gc_private = (GdkGCPrivate*) gc;
+  g_return_if_fail (GDK_IS_GC (gc));
 
   point.x = x;
   point.y = y;
@@ -206,13 +203,10 @@ gdk_draw_line (GdkDrawable *drawable,
 	       gint         x2,
 	       gint         y2)
 {
-  GdkGCPrivate *gc_private;
   GdkSegment segment;
 
   g_return_if_fail (GDK_IS_DRAWABLE (drawable));
-  g_return_if_fail (gc != NULL);
-
-  gc_private = (GdkGCPrivate*) gc;
+  g_return_if_fail (GDK_IS_GC (gc));
 
   segment.x1 = x1;
   segment.y1 = y1;
@@ -231,7 +225,7 @@ gdk_draw_rectangle (GdkDrawable *drawable,
 		    gint         height)
 {  
   g_return_if_fail (GDK_IS_DRAWABLE (drawable));
-  g_return_if_fail (gc != NULL);
+  g_return_if_fail (GDK_IS_GC (gc));
 
   if (width < 0 || height < 0)
     {
@@ -262,7 +256,7 @@ gdk_draw_arc (GdkDrawable *drawable,
 	      gint         angle2)
 {  
   g_return_if_fail (GDK_IS_DRAWABLE (drawable));
-  g_return_if_fail (gc != NULL);
+  g_return_if_fail (GDK_IS_GC (gc));
 
   if (width < 0 || height < 0)
     {
@@ -289,7 +283,7 @@ gdk_draw_polygon (GdkDrawable *drawable,
 		  gint         npoints)
 {
   g_return_if_fail (GDK_IS_DRAWABLE (drawable));
-  g_return_if_fail (gc != NULL);
+  g_return_if_fail (GDK_IS_GC (gc));
 
   GDK_DRAWABLE_GET_CLASS (drawable)->draw_polygon (drawable, gc, filled,
 							 points, npoints);
@@ -329,7 +323,7 @@ gdk_draw_text (GdkDrawable *drawable,
 {
   g_return_if_fail (GDK_IS_DRAWABLE (drawable));
   g_return_if_fail (font != NULL);
-  g_return_if_fail (gc != NULL);
+  g_return_if_fail (GDK_IS_GC (gc));
   g_return_if_fail (text != NULL);
 
   GDK_DRAWABLE_GET_CLASS (drawable)->draw_text (drawable, font, gc, x, y, text, text_length);
@@ -346,7 +340,7 @@ gdk_draw_text_wc (GdkDrawable	 *drawable,
 {
   g_return_if_fail (GDK_IS_DRAWABLE (drawable));
   g_return_if_fail (font != NULL);
-  g_return_if_fail (gc != NULL);
+  g_return_if_fail (GDK_IS_GC (gc));
   g_return_if_fail (text != NULL);
 
   GDK_DRAWABLE_GET_CLASS (drawable)->draw_text_wc (drawable, font, gc, x, y, text, text_length);
@@ -365,7 +359,7 @@ gdk_draw_drawable (GdkDrawable *drawable,
 {
   g_return_if_fail (GDK_IS_DRAWABLE (drawable));
   g_return_if_fail (src != NULL);
-  g_return_if_fail (gc != NULL);
+  g_return_if_fail (GDK_IS_GC (gc));
 
   if (width < 0 || height < 0)
     {
@@ -398,7 +392,7 @@ gdk_draw_image (GdkDrawable *drawable,
 {
   g_return_if_fail (GDK_IS_DRAWABLE (drawable));
   g_return_if_fail (image != NULL);
-  g_return_if_fail (gc != NULL);
+  g_return_if_fail (GDK_IS_GC (gc));
 
   if (width == -1)
     width = image->width;
@@ -417,7 +411,7 @@ gdk_draw_points (GdkDrawable *drawable,
 {
   g_return_if_fail (GDK_IS_DRAWABLE (drawable));
   g_return_if_fail ((points != NULL) && (npoints > 0));
-  g_return_if_fail (gc != NULL);
+  g_return_if_fail (GDK_IS_GC (gc));
   g_return_if_fail (npoints >= 0);
 
   if (npoints == 0)
@@ -438,7 +432,7 @@ gdk_draw_segments (GdkDrawable *drawable,
     return;
 
   g_return_if_fail (segs != NULL);
-  g_return_if_fail (gc != NULL);
+  g_return_if_fail (GDK_IS_GC (gc));
   g_return_if_fail (nsegs >= 0);
 
   GDK_DRAWABLE_GET_CLASS (drawable)->draw_segments (drawable, gc, segs, nsegs);
@@ -453,7 +447,7 @@ gdk_draw_lines (GdkDrawable *drawable,
 
   g_return_if_fail (GDK_IS_DRAWABLE (drawable));
   g_return_if_fail (points != NULL);
-  g_return_if_fail (gc != NULL);
+  g_return_if_fail (GDK_IS_GC (gc));
   g_return_if_fail (npoints >= 0);
 
   if (npoints == 0)
diff --git a/gdk/gdkgc.c b/gdk/gdkgc.c
index a5f77884ec..5e4b963242 100644
--- a/gdk/gdkgc.c
+++ b/gdk/gdkgc.c
@@ -29,21 +29,62 @@
 #include "gdkgc.h"
 #include "gdkprivate.h"
 
-GdkGC*
-gdk_gc_alloc (void)
+static void gdk_gc_init       (GdkGC      *gc);
+static void gdk_gc_class_init (GdkGCClass *klass);
+static void gdk_gc_finalize   (GObject           *object);
+
+static gpointer parent_class = NULL;
+
+GType
+gdk_gc_get_type (void)
 {
-  GdkGCPrivate *private;
+  static GType object_type = 0;
 
-  private = g_new (GdkGCPrivate, 1);
-  private->ref_count = 1;
-  private->klass = NULL;
-  private->klass_data = NULL;
-  private->clip_x_origin = 0;
-  private->clip_y_origin = 0;
-  private->ts_x_origin = 0;
-  private->ts_y_origin = 0;
+  if (!object_type)
+    {
+      static const GTypeInfo object_info =
+      {
+        sizeof (GdkGCClass),
+        (GBaseInitFunc) NULL,
+        (GBaseFinalizeFunc) NULL,
+        (GClassInitFunc) gdk_gc_class_init,
+        NULL,           /* class_finalize */
+        NULL,           /* class_data */
+        sizeof (GdkGC),
+        0,              /* n_preallocs */
+        (GInstanceInitFunc) gdk_gc_init,
+      };
+      
+      object_type = g_type_register_static (G_TYPE_OBJECT,
+                                            "GdkGC",
+                                            &object_info);
+    }
+  
+  return object_type;
+}
 
-  return (GdkGC *)private;
+static void
+gdk_gc_init (GdkGC *gc)
+{
+
+}
+
+static void
+gdk_gc_class_init (GdkGCClass *klass)
+{
+  GObjectClass *object_class = G_OBJECT_CLASS (klass);
+
+  parent_class = g_type_class_peek (G_TYPE_OBJECT);
+
+  object_class->finalize = gdk_gc_finalize;
+}
+
+static void
+gdk_gc_finalize (GObject *object)
+{
+  GdkGC *gc = GDK_GC (object);
+  
+  G_OBJECT_CLASS (parent_class)->finalize (object);
 }
 
 GdkGC*
@@ -63,7 +104,6 @@ gdk_gc_new_with_values (GdkDrawable	*drawable,
 			GdkGCValuesMask	 values_mask)
 {
   GdkGC *gc;
-  GdkGCPrivate *private;
 
   g_return_val_if_fail (drawable != NULL, NULL);
 
@@ -73,16 +113,14 @@ gdk_gc_new_with_values (GdkDrawable	*drawable,
   gc = GDK_DRAWABLE_GET_CLASS (drawable)->create_gc (drawable,
                                                      values,
                                                      values_mask);
-  private = (GdkGCPrivate *)gc;
-  
   if (values_mask & GDK_GC_CLIP_X_ORIGIN)
-    private->clip_x_origin = values->clip_x_origin;
+    gc->clip_x_origin = values->clip_x_origin;
   if (values_mask & GDK_GC_CLIP_Y_ORIGIN)
-    private->clip_y_origin = values->clip_y_origin;
+    gc->clip_y_origin = values->clip_y_origin;
   if (values_mask & GDK_GC_TS_X_ORIGIN)
-    private->ts_x_origin = values->ts_x_origin;
+    gc->ts_x_origin = values->ts_x_origin;
   if (values_mask & GDK_GC_TS_Y_ORIGIN)
-    private->ts_y_origin = values->ts_y_origin;
+    gc->ts_y_origin = values->ts_y_origin;
 
   return gc;
 }
@@ -90,10 +128,7 @@ gdk_gc_new_with_values (GdkDrawable	*drawable,
 GdkGC *
 gdk_gc_ref (GdkGC *gc)
 {
-  GdkGCPrivate *private = (GdkGCPrivate*) gc;
-
-  g_return_val_if_fail (gc != NULL, NULL);
-  private->ref_count += 1;
+  g_object_ref (G_OBJECT (gc));
 
   return gc;
 }
@@ -101,28 +136,17 @@ gdk_gc_ref (GdkGC *gc)
 void
 gdk_gc_unref (GdkGC *gc)
 {
-  GdkGCPrivate *private = (GdkGCPrivate*) gc;
-  
-  g_return_if_fail (gc != NULL);
-  g_return_if_fail (private->ref_count > 0);
-  
-  private->ref_count--;
-
-  if (private->ref_count == 0)
-    {
-      private->klass->destroy (gc);
-      g_free (private);
-    }
+  g_object_unref (G_OBJECT (gc));
 }
 
 void
 gdk_gc_get_values (GdkGC       *gc,
 		   GdkGCValues *values)
 {
-  g_return_if_fail (gc != NULL);
+  g_return_if_fail (GDK_IS_GC (gc));
   g_return_if_fail (values != NULL);
 
-  ((GdkGCPrivate *)gc)->klass->get_values (gc, values);
+  GDK_GC_GET_CLASS (gc)->get_values (gc, values);
 }
 
 void
@@ -130,21 +154,19 @@ gdk_gc_set_values (GdkGC           *gc,
 		   GdkGCValues	   *values,
 		   GdkGCValuesMask  values_mask)
 {
-  GdkGCPrivate *private = (GdkGCPrivate *)gc;
-  
-  g_return_if_fail (gc != NULL);
+  g_return_if_fail (GDK_IS_GC (gc));
   g_return_if_fail (values != NULL);
 
   if (values_mask & GDK_GC_CLIP_X_ORIGIN)
-    private->clip_x_origin = values->clip_x_origin;
+    gc->clip_x_origin = values->clip_x_origin;
   if (values_mask & GDK_GC_CLIP_Y_ORIGIN)
-    private->clip_y_origin = values->clip_y_origin;
+    gc->clip_y_origin = values->clip_y_origin;
   if (values_mask & GDK_GC_TS_X_ORIGIN)
-    private->ts_x_origin = values->ts_x_origin;
+    gc->ts_x_origin = values->ts_x_origin;
   if (values_mask & GDK_GC_TS_Y_ORIGIN)
-    private->ts_y_origin = values->ts_y_origin;
+    gc->ts_y_origin = values->ts_y_origin;
   
-  private->klass->set_values (gc, values, values_mask);
+  GDK_GC_GET_CLASS (gc)->set_values (gc, values, values_mask);
 }
 
 void
@@ -153,7 +175,7 @@ gdk_gc_set_foreground (GdkGC	*gc,
 {
   GdkGCValues values;
 
-  g_return_if_fail (gc != NULL);
+  g_return_if_fail (GDK_IS_GC (gc));
   g_return_if_fail (color != NULL);
 
   values.foreground = *color;
@@ -166,7 +188,7 @@ gdk_gc_set_background (GdkGC	*gc,
 {
   GdkGCValues values;
 
-  g_return_if_fail (gc != NULL);
+  g_return_if_fail (GDK_IS_GC (gc));
   g_return_if_fail (color != NULL);
 
   values.background = *color;
@@ -179,7 +201,7 @@ gdk_gc_set_font (GdkGC	 *gc,
 {
   GdkGCValues values;
 
-  g_return_if_fail (gc != NULL);
+  g_return_if_fail (GDK_IS_GC (gc));
   g_return_if_fail (font != NULL);
 
   values.font = font;
@@ -192,7 +214,7 @@ gdk_gc_set_function (GdkGC	 *gc,
 {
   GdkGCValues values;
 
-  g_return_if_fail (gc != NULL);
+  g_return_if_fail (GDK_IS_GC (gc));
 
   values.function = function;
   gdk_gc_set_values (gc, &values, GDK_GC_FUNCTION);
@@ -204,7 +226,7 @@ gdk_gc_set_fill (GdkGC	 *gc,
 {
   GdkGCValues values;
 
-  g_return_if_fail (gc != NULL);
+  g_return_if_fail (GDK_IS_GC (gc));
 
   values.fill = fill;
   gdk_gc_set_values (gc, &values, GDK_GC_FILL);
@@ -216,7 +238,7 @@ gdk_gc_set_tile (GdkGC	   *gc,
 {
   GdkGCValues values;
 
-  g_return_if_fail (gc != NULL);
+  g_return_if_fail (GDK_IS_GC (gc));
 
   values.tile = tile;
   gdk_gc_set_values (gc, &values, GDK_GC_TILE);
@@ -228,7 +250,7 @@ gdk_gc_set_stipple (GdkGC     *gc,
 {
   GdkGCValues values;
 
-  g_return_if_fail (gc != NULL);
+  g_return_if_fail (GDK_IS_GC (gc));
 
   values.stipple = stipple;
   gdk_gc_set_values (gc, &values, GDK_GC_STIPPLE);
@@ -241,7 +263,7 @@ gdk_gc_set_ts_origin (GdkGC *gc,
 {
   GdkGCValues values;
 
-  g_return_if_fail (gc != NULL);
+  g_return_if_fail (GDK_IS_GC (gc));
 
   values.ts_x_origin = x;
   values.ts_y_origin = y;
@@ -257,7 +279,7 @@ gdk_gc_set_clip_origin (GdkGC *gc,
 {
   GdkGCValues values;
 
-  g_return_if_fail (gc != NULL);
+  g_return_if_fail (GDK_IS_GC (gc));
 
   values.clip_x_origin = x;
   values.clip_y_origin = y;
@@ -272,7 +294,7 @@ gdk_gc_set_clip_mask (GdkGC	*gc,
 {
   GdkGCValues values;
   
-  g_return_if_fail (gc != NULL);
+  g_return_if_fail (GDK_IS_GC (gc));
   
   values.clip_mask = mask;
   gdk_gc_set_values (gc, &values, GDK_GC_CLIP_MASK);
@@ -285,7 +307,7 @@ gdk_gc_set_subwindow (GdkGC	       *gc,
 {
   GdkGCValues values;
 
-  g_return_if_fail (gc != NULL);
+  g_return_if_fail (GDK_IS_GC (gc));
 
   values.subwindow_mode = mode;
   gdk_gc_set_values (gc, &values, GDK_GC_SUBWINDOW);
@@ -297,7 +319,7 @@ gdk_gc_set_exposures (GdkGC     *gc,
 {
   GdkGCValues values;
 
-  g_return_if_fail (gc != NULL);
+  g_return_if_fail (GDK_IS_GC (gc));
 
   values.graphics_exposures = exposures;
   gdk_gc_set_values (gc, &values, GDK_GC_EXPOSURES);
@@ -330,8 +352,8 @@ gdk_gc_set_dashes (GdkGC *gc,
 		   gint8  dash_list[],
 		   gint   n)
 {
-  g_return_if_fail (gc != NULL);
+  g_return_if_fail (GDK_IS_GC (gc));
   g_return_if_fail (dash_list != NULL);
 
-  ((GdkGCPrivate *)gc)->klass->set_dashes (gc, dash_offset, dash_list, n);
+  GDK_GC_GET_CLASS (gc)->set_dashes (gc, dash_offset, dash_list, n);
 }
diff --git a/gdk/gdkgc.h b/gdk/gdkgc.h
index 072ddfe74e..86dfa53148 100644
--- a/gdk/gdkgc.h
+++ b/gdk/gdkgc.h
@@ -150,14 +150,27 @@ struct _GdkGCValues
   GdkJoinStyle	    join_style;
 };
 
+#define GDK_TYPE_GC              (gdk_gc_get_type ())
+#define GDK_GC(object)           (G_TYPE_CHECK_INSTANCE_CAST ((object), GDK_TYPE_GC, GdkGC))
+#define GDK_GC_CLASS(klass)      (G_TYPE_CHECK_CLASS_CAST ((klass), GDK_TYPE_GC, GdkGCClass))
+#define GDK_IS_GC(object)        (G_TYPE_CHECK_INSTANCE_TYPE ((object), GDK_TYPE_GC))
+#define GDK_IS_GC_CLASS(klass)   (G_TYPE_CHECK_CLASS_TYPE ((klass), GDK_TYPE_GC))
+#define GDK_GC_GET_CLASS(obj)    (G_TYPE_INSTANCE_GET_CLASS ((obj), GDK_TYPE_GC, GdkGCClass))
+
 struct _GdkGC
 {
-  gint dummy_var;
+  GObject parent_instance;
+
+  gint clip_x_origin;
+  gint clip_y_origin;
+  gint ts_x_origin;
+  gint ts_y_origin;
 };
 
 struct _GdkGCClass 
 {
-  void (*destroy)        (GdkGC          *gc);
+  GObjectClass parent_class;
+  
   void (*get_values)     (GdkGC          *gc,
 			  GdkGCValues    *values);
   void (*set_values)     (GdkGC          *gc,
@@ -170,14 +183,11 @@ struct _GdkGCClass
 };
 
 
+GType  gdk_gc_get_type            (void);
 GdkGC *gdk_gc_new		  (GdkDrawable	    *drawable);
-GdkGC *gdk_gc_alloc		  (void);
-
 GdkGC *gdk_gc_new_with_values	  (GdkDrawable	    *drawable,
 				   GdkGCValues	    *values,
 				   GdkGCValuesMask   values_mask);
-void   gdk_gc_init                (GdkGC            *gc,
-				   GdkGCClass       *klass);
 GdkGC *gdk_gc_ref		  (GdkGC	    *gc);
 void   gdk_gc_unref		  (GdkGC	    *gc);
 void   gdk_gc_get_values	  (GdkGC	    *gc,
diff --git a/gdk/gdkprivate.h b/gdk/gdkprivate.h
index 8fad56cbfc..3df7bbbf6d 100644
--- a/gdk/gdkprivate.h
+++ b/gdk/gdkprivate.h
@@ -51,7 +51,6 @@ extern "C" {
 #define gdk_pixmap_lookup(xid)	   ((GdkPixmap*) gdk_xid_table_lookup (xid))
 #define gdk_font_lookup(xid)	   ((GdkFont*) gdk_xid_table_lookup (xid))
 
-typedef struct _GdkGCPrivate	       GdkGCPrivate;
 typedef struct _GdkColorInfo           GdkColorInfo;
 typedef struct _GdkFontPrivate	       GdkFontPrivate;
 typedef struct _GdkEventFilter	       GdkEventFilter;
@@ -63,18 +62,6 @@ struct _GdkFontPrivate
   guint ref_count;
 };
 
-struct _GdkGCPrivate
-{
-  guint ref_count;
-  GdkGCClass *klass;
-  gpointer klass_data;
-
-  gint clip_x_origin;
-  gint clip_y_origin;
-  gint ts_x_origin;
-  gint ts_y_origin;
-};
-
 typedef enum {
   GDK_COLOR_WRITEABLE = 1 << 0
 } GdkColorInfoFlags;
diff --git a/gdk/gdkwindow.c b/gdk/gdkwindow.c
index 3720f53cc4..13896dd0b8 100644
--- a/gdk/gdkwindow.c
+++ b/gdk/gdkwindow.c
@@ -823,10 +823,10 @@ gdk_window_get_offsets (GdkWindow *window,
 
 #define OFFSET_GC(gc)                                         \
     gint x_offset, y_offset; 				      \
-    gint old_clip_x = ((GdkGCPrivate *)gc)->clip_x_origin;    \
-    gint old_clip_y = ((GdkGCPrivate *)gc)->clip_y_origin;    \
-    gint old_ts_x = ((GdkGCPrivate *)gc)->ts_x_origin;        \
-    gint old_ts_y = ((GdkGCPrivate *)gc)->ts_y_origin;        \
+    gint old_clip_x = (gc)->clip_x_origin;    \
+    gint old_clip_y = (gc)->clip_y_origin;    \
+    gint old_ts_x = (gc)->ts_x_origin;        \
+    gint old_ts_y = (gc)->ts_y_origin;        \
     gdk_window_get_offsets (drawable, &x_offset, &y_offset);  \
     if (x_offset != 0 || y_offset != 0)             	      \
       {                                                       \
diff --git a/gdk/x11/gdkdrawable-x11.c b/gdk/x11/gdkdrawable-x11.c
index d542bc0013..cb7a31edcf 100644
--- a/gdk/x11/gdkdrawable-x11.c
+++ b/gdk/x11/gdkdrawable-x11.c
@@ -24,6 +24,36 @@
  * GTK+ at ftp://ftp.gtk.org/pub/gtk/. 
  */
 
+
+#include <config.h>
+
+/* gcc -ansi -pedantic on GNU/Linux causes warnings and errors
+ * unless this is defined:
+ * warning: #warning "Files using this header must be compiled with _SVID_SOURCE or _XOPEN_SOURCE"
+ */
+#ifndef _XOPEN_SOURCE
+#  define _XOPEN_SOURCE 1
+#endif
+
+#include <stdlib.h>
+#include <sys/types.h>
+
+#if defined (HAVE_IPC_H) && defined (HAVE_SHM_H) && defined (HAVE_XSHM_H)
+#define USE_SHM
+#endif
+
+#ifdef USE_SHM
+#include <sys/ipc.h>
+#include <sys/shm.h>
+#endif /* USE_SHM */
+
+#include <X11/Xlib.h>
+#include <X11/Xutil.h>
+
+#ifdef USE_SHM
+#include <X11/extensions/XShm.h>
+#endif /* USE_SHM */
+
 #include "gdkprivate-x11.h"
 #include "gdkdrawable-x11.h"
 #include "gdkpixmap-x11.h"
diff --git a/gdk/x11/gdkgc-x11.c b/gdk/x11/gdkgc-x11.c
index 5da2cbf901..b0ed62d47a 100644
--- a/gdk/x11/gdkgc-x11.c
+++ b/gdk/x11/gdkgc-x11.c
@@ -11,8 +11,7 @@ static void gdk_x11_gc_values_to_xvalues (GdkGCValues    *values,
 					  GdkGCValuesMask mask,
 					  XGCValues      *xvalues,
 					  unsigned long  *xvalues_mask);
-     
-static void gdk_x11_gc_destroy    (GdkGC           *gc);
+
 static void gdk_x11_gc_get_values (GdkGC           *gc,
 				   GdkGCValues     *values);
 static void gdk_x11_gc_set_values (GdkGC           *gc,
@@ -23,12 +22,74 @@ static void gdk_x11_gc_set_dashes (GdkGC           *gc,
 				   gchar            dash_list[],
 				   gint             n);
 
-static GdkGCClass gdk_x11_gc_class = {
-  gdk_x11_gc_destroy,
-  gdk_x11_gc_get_values,
-  gdk_x11_gc_set_values,
-  gdk_x11_gc_set_dashes
-};
+static void gdk_windowing_gc_init       (GdkWindowingGC      *windowing_gc);
+static void gdk_windowing_gc_class_init (GdkWindowingGCClass *klass);
+static void gdk_windowing_gc_finalize   (GObject           *object);
+
+static gpointer parent_class = NULL;
+
+GType
+gdk_windowing_gc_get_type (void)
+{
+  static GType object_type = 0;
+
+  if (!object_type)
+    {
+      static const GTypeInfo object_info =
+      {
+        sizeof (GdkWindowingGCClass),
+        (GBaseInitFunc) NULL,
+        (GBaseFinalizeFunc) NULL,
+        (GClassInitFunc) gdk_windowing_gc_class_init,
+        NULL,           /* class_finalize */
+        NULL,           /* class_data */
+        sizeof (GdkWindowingGC),
+        0,              /* n_preallocs */
+        (GInstanceInitFunc) gdk_windowing_gc_init,
+      };
+      
+      object_type = g_type_register_static (GDK_TYPE_GC,
+                                            "GdkWindowingGC",
+                                            &object_info);
+    }
+  
+  return object_type;
+}
+
+static void
+gdk_windowing_gc_init (GdkWindowingGC *windowing_gc)
+{
+
+}
+
+static void
+gdk_windowing_gc_class_init (GdkWindowingGCClass *klass)
+{
+  GObjectClass *object_class = G_OBJECT_CLASS (klass);
+  GdkGCClass *gc_class = GDK_GC_CLASS (klass);
+  
+  parent_class = g_type_class_peek (GDK_TYPE_GC);
+
+  object_class->finalize = gdk_windowing_gc_finalize;
+
+  gc_class->get_values = gdk_x11_gc_get_values;
+  gc_class->set_values = gdk_x11_gc_set_values;
+  gc_class->set_dashes = gdk_x11_gc_set_dashes;
+}
+
+static void
+gdk_windowing_gc_finalize (GObject *object)
+{
+  GdkWindowingGC *windowing_gc = GDK_WINDOWING_GC (object);
+  
+  if (windowing_gc->clip_region)
+    gdk_region_destroy (windowing_gc->clip_region);
+  
+  XFreeGC (GDK_GC_XDISPLAY (windowing_gc), GDK_GC_XGC (windowing_gc));
+  
+  G_OBJECT_CLASS (parent_class)->finalize (object);
+}
+
 
 GdkGC *
 _gdk_x11_gc_new (GdkDrawable      *drawable,
@@ -36,8 +97,7 @@ _gdk_x11_gc_new (GdkDrawable      *drawable,
 		 GdkGCValuesMask   values_mask)
 {
   GdkGC *gc;
-  GdkGCPrivate *private;
-  GdkGCXData *data;
+  GdkWindowingGC *private;
   
   XGCValues xvalues;
   unsigned long xvalues_mask;
@@ -47,27 +107,24 @@ _gdk_x11_gc_new (GdkDrawable      *drawable,
    */
   g_return_val_if_fail (GDK_IS_DRAWABLE_IMPL (drawable), NULL);
   
-  gc = gdk_gc_alloc ();
-  private = (GdkGCPrivate *)gc;
+  gc = GDK_GC (g_type_create_instance (gdk_windowing_gc_get_type ()));
+  private = GDK_WINDOWING_GC (gc);
 
-  private->klass = &gdk_x11_gc_class;
-  private->klass_data = data = g_new (GdkGCXData, 1);
-
-  data->dirty_mask = 0;
-  data->clip_region = NULL;
+  private->dirty_mask = 0;
+  private->clip_region = NULL;
     
-  GDK_GC_XDATA (gc)->xdisplay = GDK_DRAWABLE_IMPL (drawable)->xdisplay;
+  private->xdisplay = GDK_DRAWABLE_IMPL (drawable)->xdisplay;
 
   if (values_mask & (GDK_GC_CLIP_X_ORIGIN | GDK_GC_CLIP_Y_ORIGIN))
     {
       values_mask &= ~(GDK_GC_CLIP_X_ORIGIN | GDK_GC_CLIP_Y_ORIGIN);
-      data->dirty_mask |= GDK_GC_DIRTY_CLIP;
+      private->dirty_mask |= GDK_GC_DIRTY_CLIP;
     }
 
   if (values_mask & (GDK_GC_TS_X_ORIGIN | GDK_GC_TS_Y_ORIGIN))
     {
       values_mask &= ~(GDK_GC_TS_X_ORIGIN | GDK_GC_TS_Y_ORIGIN);
-      data->dirty_mask |= GDK_GC_DIRTY_TS;
+      private->dirty_mask |= GDK_GC_DIRTY_TS;
     }
 
   xvalues.function = GXcopy;
@@ -79,62 +136,51 @@ _gdk_x11_gc_new (GdkDrawable      *drawable,
 
   gdk_x11_gc_values_to_xvalues (values, values_mask, &xvalues, &xvalues_mask);
   
-  data->xgc = XCreateGC (GDK_GC_XDISPLAY (gc),
-                         GDK_DRAWABLE_IMPL (drawable)->xid,
-			 xvalues_mask, &xvalues);
+  private->xgc = XCreateGC (GDK_GC_XDISPLAY (gc),
+                            GDK_DRAWABLE_IMPL (drawable)->xid,
+                            xvalues_mask, &xvalues);
 
   return gc;
 }
 
-static void
-gdk_x11_gc_destroy (GdkGC *gc)
-{
-  if (GDK_GC_XDATA (gc)->clip_region)
-    gdk_region_destroy (GDK_GC_XDATA (gc)->clip_region);
-  
-  XFreeGC (GDK_GC_XDISPLAY (gc), GDK_GC_XGC (gc));
-  g_free (GDK_GC_XDATA (gc));
-}
-
 GC
 _gdk_x11_gc_flush (GdkGC *gc)
 {
-  GdkGCPrivate *private = (GdkGCPrivate *)gc;
-  GdkGCXData *data = GDK_GC_XDATA (gc);
+  GdkWindowingGC *private = GDK_WINDOWING_GC (gc);
 
-  if (data->dirty_mask & GDK_GC_DIRTY_CLIP)
+  if (private->dirty_mask & GDK_GC_DIRTY_CLIP)
     {
-      if (!data->clip_region)
+      if (!private->clip_region)
 	XSetClipOrigin (GDK_GC_XDISPLAY (gc), GDK_GC_XGC (gc),
-			private->clip_x_origin, private->clip_y_origin);
+			gc->clip_x_origin, gc->clip_y_origin);
       else
 	{
-	  XRectangle *rectangles = g_new (XRectangle, data->clip_region->numRects);
-	  GdkRegionBox *boxes = data->clip_region->rects;
+	  XRectangle *rectangles = g_new (XRectangle, private->clip_region->numRects);
+	  GdkRegionBox *boxes = private->clip_region->rects;
 	  int i;
 
-	  for (i=0; i<data->clip_region->numRects; i++)
+	  for (i=0; i<private->clip_region->numRects; i++)
 	    {
-	      rectangles[i].x = CLAMP (boxes[i].x1 + private->clip_x_origin, G_MINSHORT, G_MAXSHORT);
-	      rectangles[i].y = CLAMP (boxes[i].y1 + private->clip_y_origin, G_MINSHORT, G_MAXSHORT);
-	      rectangles[i].width = CLAMP (boxes[i].x2 + private->clip_x_origin, G_MINSHORT, G_MAXSHORT) - rectangles[i].x;
-	      rectangles[i].height = CLAMP (boxes[i].y2 + private->clip_y_origin, G_MINSHORT, G_MAXSHORT) - rectangles[i].y;
+	      rectangles[i].x = CLAMP (boxes[i].x1 + gc->clip_x_origin, G_MINSHORT, G_MAXSHORT);
+	      rectangles[i].y = CLAMP (boxes[i].y1 + gc->clip_y_origin, G_MINSHORT, G_MAXSHORT);
+	      rectangles[i].width = CLAMP (boxes[i].x2 + gc->clip_x_origin, G_MINSHORT, G_MAXSHORT) - rectangles[i].x;
+	      rectangles[i].height = CLAMP (boxes[i].y2 + gc->clip_y_origin, G_MINSHORT, G_MAXSHORT) - rectangles[i].y;
 	    }
 	  
 	  XSetClipRectangles(GDK_GC_XDISPLAY (gc), GDK_GC_XGC (gc), 0, 0, rectangles,
-			     data->clip_region->numRects, YXBanded);
+			     private->clip_region->numRects, YXBanded);
 
 	  g_free (rectangles);
 	}
     }
 
-  if (data->dirty_mask & GDK_GC_DIRTY_TS)
+  if (private->dirty_mask & GDK_GC_DIRTY_TS)
     {
       XSetTSOrigin (GDK_GC_XDISPLAY (gc), GDK_GC_XGC (gc),
-		    private->ts_x_origin, private->ts_y_origin);
+		    gc->ts_x_origin, gc->ts_y_origin);
     }
 
-  data->dirty_mask = 0;
+  private->dirty_mask = 0;
   return GDK_GC_XGC (gc);
 }
 
@@ -287,32 +333,32 @@ gdk_x11_gc_set_values (GdkGC           *gc,
 		       GdkGCValues     *values,
 		       GdkGCValuesMask  values_mask)
 {
-  GdkGCXData *data;
+  GdkWindowingGC *windowing_gc;
   XGCValues xvalues;
   unsigned long xvalues_mask = 0;
 
-  g_return_if_fail (gc != NULL);
+  g_return_if_fail (GDK_IS_GC (gc));
 
-  data = GDK_GC_XDATA (gc);
+  windowing_gc = GDK_WINDOWING_GC (gc);
 
   if (values_mask & (GDK_GC_CLIP_X_ORIGIN | GDK_GC_CLIP_Y_ORIGIN))
     {
       values_mask &= ~(GDK_GC_CLIP_X_ORIGIN | GDK_GC_CLIP_Y_ORIGIN);
-      data->dirty_mask |= GDK_GC_DIRTY_CLIP;
+      windowing_gc->dirty_mask |= GDK_GC_DIRTY_CLIP;
     }
 
   if (values_mask & (GDK_GC_TS_X_ORIGIN | GDK_GC_TS_Y_ORIGIN))
     {
       values_mask &= ~(GDK_GC_TS_X_ORIGIN | GDK_GC_TS_Y_ORIGIN);
-      data->dirty_mask |= GDK_GC_DIRTY_TS;
+      windowing_gc->dirty_mask |= GDK_GC_DIRTY_TS;
     }
 
   if (values_mask & GDK_GC_CLIP_MASK)
     {
-      if (data->clip_region)
+      if (windowing_gc->clip_region)
 	{
-	  gdk_region_destroy (data->clip_region);
-	  data->clip_region = NULL;
+	  gdk_region_destroy (windowing_gc->clip_region);
+	  windowing_gc->clip_region = NULL;
 	}
     }
 
@@ -330,7 +376,7 @@ gdk_x11_gc_set_dashes (GdkGC *gc,
 		       gchar  dash_list[],
 		       gint   n)
 {
-  g_return_if_fail (gc != NULL);
+  g_return_if_fail (GDK_IS_GC (gc));
   g_return_if_fail (dash_list != NULL);
 
   XSetDashes (GDK_GC_XDISPLAY (gc), GDK_GC_XGC (gc),
@@ -552,64 +598,62 @@ void
 gdk_gc_set_clip_rectangle (GdkGC	*gc,
 			   GdkRectangle *rectangle)
 {
-  GdkGCPrivate *private = (GdkGCPrivate *)gc;
-  GdkGCXData *data;
+  GdkWindowingGC *windowing_gc;
 
-  g_return_if_fail (gc != NULL);
+  g_return_if_fail (GDK_IS_GC (gc));
 
-  data = GDK_GC_XDATA (gc);
+  windowing_gc = GDK_WINDOWING_GC (gc);
 
-  if (data->clip_region)
-    gdk_region_destroy (data->clip_region);
+  if (windowing_gc->clip_region)
+    gdk_region_destroy (windowing_gc->clip_region);
 
   if (rectangle)
-    data->clip_region = gdk_region_rectangle (rectangle);
+    windowing_gc->clip_region = gdk_region_rectangle (rectangle);
   else
     {
-      data->clip_region = NULL;
+      windowing_gc->clip_region = NULL;
       XSetClipMask (GDK_GC_XDISPLAY (gc), GDK_GC_XGC (gc), None);
     }
 
-  private->clip_x_origin = 0;
-  private->clip_y_origin = 0;
+  gc->clip_x_origin = 0;
+  gc->clip_y_origin = 0;
   
-  data->dirty_mask |= GDK_GC_DIRTY_CLIP;
+  windowing_gc->dirty_mask |= GDK_GC_DIRTY_CLIP;
 } 
 
 void
 gdk_gc_set_clip_region (GdkGC	  *gc,
 			GdkRegion *region)
 {
-  GdkGCPrivate *private = (GdkGCPrivate *)gc;
-  GdkGCXData *data;
+  GdkWindowingGC *windowing_gc;
 
-  g_return_if_fail (gc != NULL);
+  g_return_if_fail (GDK_IS_GC (gc));
 
-  data = GDK_GC_XDATA (gc);
+  windowing_gc = GDK_WINDOWING_GC (gc);
 
-  if (data->clip_region)
-    gdk_region_destroy (data->clip_region);
+  if (windowing_gc->clip_region)
+    gdk_region_destroy (windowing_gc->clip_region);
 
   if (region)
-    data->clip_region = gdk_region_copy (region);
+    windowing_gc->clip_region = gdk_region_copy (region);
   else
     {
-      data->clip_region = NULL;
+      windowing_gc->clip_region = NULL;
       XSetClipMask (GDK_GC_XDISPLAY (gc), GDK_GC_XGC (gc), None);
     }
   
-  private->clip_x_origin = 0;
-  private->clip_y_origin = 0;
+  gc->clip_x_origin = 0;
+  gc->clip_y_origin = 0;
   
-  data->dirty_mask |= GDK_GC_DIRTY_CLIP;
+  windowing_gc->dirty_mask |= GDK_GC_DIRTY_CLIP;
 }
 
 
 void
 gdk_gc_copy (GdkGC *dst_gc, GdkGC *src_gc)
 {
-  g_return_if_fail (dst_gc != NULL);
-  g_return_if_fail (src_gc != NULL);
+  g_return_if_fail (GDK_IS_WINDOWING_GC (dst_gc));
+  g_return_if_fail (GDK_IS_WINDOWING_GC (src_gc));
   
   XCopyGC (GDK_GC_XDISPLAY (src_gc), GDK_GC_XGC (src_gc), ~((~1) << GCLastBit),
 	   GDK_GC_XGC (dst_gc));
diff --git a/gdk/x11/gdkimage-x11.c b/gdk/x11/gdkimage-x11.c
index 9e64332586..7bb42f4032 100644
--- a/gdk/x11/gdkimage-x11.c
+++ b/gdk/x11/gdkimage-x11.c
@@ -61,7 +61,7 @@
 static GList *image_list = NULL;
 static gpointer parent_class = NULL;
 
-static void gdk_image_destroy    (GdkImage      *image);
+static void gdk_x11_image_destroy    (GdkImage      *image);
 static void gdk_image_init       (GdkImage      *image);
 static void gdk_image_class_init (GdkImageClass *klass);
 static void gdk_image_finalize   (GObject       *object);
@@ -118,7 +118,7 @@ gdk_image_finalize (GObject *object)
 {
   GdkImage *image = GDK_IMAGE (object);
 
-  gdk_image_destroy (image);
+  gdk_x11_image_destroy (image);
   
   G_OBJECT_CLASS (parent_class)->finalize (object);
 }
@@ -132,7 +132,7 @@ gdk_image_exit (void)
   while (image_list)
     {
       image = image_list->data;
-      gdk_image_destroy (image);
+      gdk_x11_image_destroy (image);
     }
 }
 
@@ -439,7 +439,7 @@ gdk_image_put_pixel (GdkImage *image,
 }
 
 static void
-gdk_image_destroy (GdkImage *image)
+gdk_x11_image_destroy (GdkImage *image)
 {
   GdkImagePrivateData *private;
 #ifdef USE_SHM
diff --git a/gdk/x11/gdkx.h b/gdk/x11/gdkx.h
index c41bd261c7..a0ec02d7a1 100644
--- a/gdk/x11/gdkx.h
+++ b/gdk/x11/gdkx.h
@@ -47,17 +47,6 @@ typedef struct _GdkVisualPrivate       GdkVisualPrivate;
 typedef struct _GdkICPrivate        GdkICPrivate;
 #endif /* USE_XIM */
 
-#define GDK_WINDOW_XDATA(win) ((GdkWindowXData *)(((GdkDrawablePrivate*)(win))->klass_data))
-#define GDK_GC_XDATA(gc) ((GdkGCXData *)(((GdkGCPrivate*)(gc))->klass_data))
-
-struct _GdkGCXData
-{
-  GC xgc;
-  Display *xdisplay;
-  GdkRegion *clip_region;
-  guint dirty_mask;
-};
-
 struct _GdkCursorPrivate
 {
   GdkCursor cursor;
@@ -112,6 +101,35 @@ struct _GdkICPrivate
 
 #endif /* USE_XIM */
 
+
+typedef struct _GdkWindowingGC      GdkWindowingGC;
+typedef struct _GdkWindowingGCClass GdkWindowingGCClass;
+
+#define GDK_TYPE_WINDOWING_GC              (gdk_windowing_gc_get_type ())
+#define GDK_WINDOWING_GC(object)           (G_TYPE_CHECK_INSTANCE_CAST ((object), GDK_TYPE_WINDOWING_GC, GdkWindowingGC))
+#define GDK_WINDOWING_GC_CLASS(klass)      (G_TYPE_CHECK_CLASS_CAST ((klass), GDK_TYPE_WINDOWING_GC, GdkWindowingGCClass))
+#define GDK_IS_WINDOWING_GC(object)        (G_TYPE_CHECK_INSTANCE_TYPE ((object), GDK_TYPE_WINDOWING_GC))
+#define GDK_IS_WINDOWING_GC_CLASS(klass)   (G_TYPE_CHECK_CLASS_TYPE ((klass), GDK_TYPE_WINDOWING_GC))
+#define GDK_WINDOWING_GC_GET_CLASS(obj)    (G_TYPE_INSTANCE_GET_CLASS ((obj), GDK_TYPE_WINDOWING_GC, GdkWindowingGCClass))
+
+struct _GdkWindowingGC
+{
+  GdkGC parent_instance;
+  
+  GC xgc;
+  Display *xdisplay;
+  GdkRegion *clip_region;
+  guint dirty_mask;
+};
+
+struct _GdkWindowingGCClass
+{
+  GdkGCClass parent_class;
+
+};
+
+GType gdk_windowing_gc_get_type (void);
+
 #define GDK_ROOT_WINDOW()             gdk_root_window
 #define GDK_ROOT_PARENT()             ((GdkWindow *)gdk_parent_root)
 #define GDK_DISPLAY()                 gdk_display
@@ -123,15 +141,15 @@ struct _GdkICPrivate
 #define GDK_DRAWABLE_XID(win)         (GDK_IS_WINDOW (win) ? GDK_WINDOW_XID (win) : GDK_PIXMAP_XID (win))
 #define GDK_IMAGE_XDISPLAY(image)     (((GdkImagePrivateData*) GDK_IMAGE (image)->windowing_data)->xdisplay)
 #define GDK_IMAGE_XIMAGE(image)       (((GdkImagePrivateData*) GDK_IMAGE (image)->windowing_data)->ximage)
-#define GDK_GC_XDISPLAY(gc)           (GDK_GC_XDATA(gc)->xdisplay)
+#define GDK_GC_XDISPLAY(gc)           (GDK_WINDOWING_GC(gc)->xdisplay)
 #define GDK_COLORMAP_XDISPLAY(cmap)   (((GdkColormapPrivateData *)GDK_COLORMAP (cmap)->windowing_data)->xdisplay)
 #define GDK_COLORMAP_XCOLORMAP(cmap)  (((GdkColormapPrivateData *)GDK_COLORMAP (cmap)->windowing_data)->xcolormap)
 #define GDK_VISUAL_XVISUAL(vis)       (((GdkVisualPrivate*) vis)->xvisual)
 #define GDK_FONT_XDISPLAY(font)       (((GdkFontPrivate*) font)->xdisplay)
 #define GDK_FONT_XFONT(font)          (((GdkFontPrivateX *)font)->xfont)
 
-#define GDK_GC_XGC(gc)       (GDK_GC_XDATA(gc)->xgc)
-#define GDK_GC_GET_XGC(gc)   (GDK_GC_XDATA(gc)->dirty_mask ? _gdk_x11_gc_flush (gc) : GDK_GC_XGC (gc))
+#define GDK_GC_XGC(gc)       (GDK_WINDOWING_GC(gc)->xgc)
+#define GDK_GC_GET_XGC(gc)   (GDK_WINDOWING_GC(gc)->dirty_mask ? _gdk_x11_gc_flush (gc) : GDK_GC_XGC (gc))
 #define GDK_WINDOW_XWINDOW    GDK_WINDOW_XID
 
 extern Display		*gdk_display;