2005-04-09  Michael Natterer  <mitch@gimp.org>

	Implement dragging and dropping in any GdkPixbuf supported
	format. Fixes bug #172794 and bug #172795.

	* app/core/gimplayer.[ch] (gimp_layer_new_from_region): new
	function which contains all stuff that was in
	gimp_layer_new_from_tiles().

	(gimp_layer_new_from_tiles): use above function.
	(gimp_layer_new_from_pixbuf): new function.

	* app/widgets/Makefile.am
	* app/widgets/gimppixbuf.[ch]: new files containing GdkPixbuf
	utility functions for clipboard and DnD.

	* app/widgets/gimpselectiondata.[ch]: removed
	gimp_selection_data_set,get_pixbuf(), GTK+ provides the same API.
	Also removed GdkAtom parameters all over the place because it's
	always the same as selection_data->target.

	* app/widgets/gimpclipboard.c: use the new pixbuf utility
	functions and gtk_selection_data_set,get_pixbuf().

	* app/widgets/widgets-enums.h
	* app/widgets/gimpdnd.[ch]: removed never-implemented
	GIMP_DND_TYPE_PNG and added a generic GIMP_DND_TYPE_PIXBUF
	instead. Added API to drag and drop GdkPixbufs which transparently
	converts from/to and GdkPixbuf-supported image format. Removed
	passing around of GdkAtoms, since they were always the same
	as selection_data->target.

	* app/widgets/gimpdnd-xds.[ch]: follow GdkAtom parameter removal.

	* app/widgets/gimpcontainertreeview.[ch]: added virtual function
	GimpContainerTreeView::drop_pixbuf().

	* app/widgets/gimpcontainertreeview-dnd.c: dispatch drop_pixbuf().

	* app/widgets/gimplayertreeview.c: implement drop_pixbuf().

	* app/widgets/gimpdrawabletreeview.c: allow to drag all drawables
	as pixbufs.

	* app/display/gimpdisplayshell-dnd.c: allow dropping of pixbufs.