-#define PSPPIRE_WINDOW_TYPE (psppire_window_get_type ())
-#define PSPPIRE_WINDOW(obj) (G_TYPE_CHECK_INSTANCE_CAST ((obj), PSPPIRE_WINDOW_TYPE, PsppireWindow))
-#define PSPPIRE_WINDOW_CLASS(class) (G_TYPE_CHECK_CLASS_CAST ((class), \
- PSPPIRE_WINDOW_TYPE, PsppireWindowClass))
-#define PSPPIRE_IS_WINDOW(obj) (G_TYPE_CHECK_INSTANCE_TYPE ((obj), \
- PSPPIRE_WINDOW_TYPE))
-#define PSPPIRE_IS_WINDOW_CLASS(class) (G_TYPE_CHECK_CLASS_TYPE ((class), \
- PSPPIRE_WINDOW_TYPE))
+
+#define PSPPIRE_TYPE_WINDOW_MODEL (psppire_window_model_get_type ())
+
+#define PSPPIRE_IS_WINDOW_MODEL(obj) (G_TYPE_CHECK_INSTANCE_TYPE ((obj), PSPPIRE_TYPE_WINDOW_MODEL))
+
+#define PSPPIRE_WINDOW_MODEL_GET_IFACE(obj) \
+ (G_TYPE_INSTANCE_GET_INTERFACE ((obj), PSPPIRE_TYPE_WINDOW_MODEL, PsppireWindowIface))