/* This file is part of GEGL.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 3 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, see <http://www.gnu.org/licenses/>.
 *
 * Copyright 2006 Øyvind Kolås <pippin@gimp.org>
 */

#ifndef __GEGL_TILE_HANDLER_EMPTY_H__
#define __GEGL_TILE_HANDLER_EMPTY_H__

#include "gegl-tile-handler.h"
#include "gegl-tile-handler-cache.h"

/***
 * GeglTileHandlerEmpty is a GeglTileHandler that create COW tiles sharing data
 * with a single empty tile if the tile is not provided by the handlers/sources
 * lower down.
 */

G_BEGIN_DECLS

#define GEGL_TYPE_TILE_HANDLER_EMPTY            (gegl_tile_handler_empty_get_type ())
#define GEGL_TILE_HANDLER_EMPTY(obj)            (G_TYPE_CHECK_INSTANCE_CAST ((obj), GEGL_TYPE_TILE_HANDLER_EMPTY, GeglTileHandlerEmpty))
#define GEGL_TILE_HANDLER_EMPTY_CLASS(klass)    (G_TYPE_CHECK_CLASS_CAST ((klass),  GEGL_TYPE_TILE_HANDLER_EMPTY, GeglTileHandlerEmptyClass))
#define GEGL_IS_TILE_HANDLER_EMPTY(obj)         (G_TYPE_CHECK_INSTANCE_TYPE ((obj), GEGL_TYPE_TILE_HANDLER_EMPTY))
#define GEGL_IS_TILE_HANDLER_EMPTY_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE ((klass),  GEGL_TYPE_TILE_HANDLER_EMPTY))
#define GEGL_TILE_HANDLER_EMPTY_GET_CLASS(obj)  (G_TYPE_INSTANCE_GET_CLASS ((obj),  GEGL_TYPE_TILE_HANDLER_EMPTY, GeglTileHandlerEmptyClass))


typedef struct _GeglTileHandlerEmpty      GeglTileHandlerEmpty;
typedef struct _GeglTileHandlerEmptyClass GeglTileHandlerEmptyClass;

struct _GeglTileHandlerEmpty
{
  GeglTileHandler         parent_instance;

  GeglTile               *tile;
  GeglTileBackend        *backend;
  GeglTileHandlerCache   *cache;
};

struct _GeglTileHandlerEmptyClass
{
  GeglTileHandlerClass parent_class;
};

GType gegl_tile_handler_empty_get_type (void) G_GNUC_CONST;
GeglTileHandler *gegl_tile_handler_empty_new (GeglTileBackend      *backend,
                                              GeglTileHandlerCache *cache);

G_END_DECLS

#endif