gimp/app/tile.h

116 lines
3.4 KiB
C

#ifndef __TILE_H__
#define __TILE_H__
#define TILE_WIDTH 64
#define TILE_HEIGHT 64
#define TILE_DEBUG
#include <sys/types.h>
#include <glib.h>
typedef struct _Tile Tile;
struct _Tile
{
short ref_count; /* reference count. when the reference count is
* non-zero then the "data" for this tile must
* be valid. when the reference count for a tile
* is 0 then the "data" for this tile must be
* NULL.
*/
guint dirty : 1; /* is the tile dirty? has it been modified? */
guint valid : 1; /* is the tile valid? */
int ewidth; /* the effective width of the tile */
int eheight; /* the effective height of the tile */
/* a tiles effective width and height may be smaller
* (but not larger) than TILE_WIDTH and TILE_HEIGHT.
* this is to handle edge tiles of a drawable.
*/
int bpp; /* the bytes per pixel (1, 2, 3 or 4) */
int tile_num; /* the number of this tile within the drawable */
guchar *data; /* the data for the tile. this may be NULL in which
* case the tile data is on disk.
*/
int swap_num; /* the index into the file table of the file to be used
* for swapping. swap_num 1 is always the global swap file.
*/
off_t swap_offset; /* the offset within the swap file of the tile data.
* if the tile data is in memory this will be set to -1.
*/
void *tm; /* A pointer to the tile manager for this tile.
* We need this in order to call the tile managers validate
* proc whenever the tile is referenced yet invalid.
*/
};
/* Initializes the fields of a tile to "good" values.
*/
void tile_init (Tile *tile,
int bpp);
/* Referencing a tile causes the reference count to be incremented.
* If the reference count was previously 0 the tile will will be
* swapped into memory from disk.
*/
#if defined (TILE_DEBUG) && defined (__GNUC__)
#define tile_ref(t) _tile_ref (t, __PRETTY_FUNCTION__)
void _tile_ref (Tile *tile, char *func_name);
#else
void tile_ref (Tile *tile);
#endif
/* Unrefercing a tile causes the reference count to be decremented.
* When the reference count reaches 0 the tile data will be swapped
* out to disk. Note that the tile may be in the tile cache which
* also references the tile causing the reference count not to
* fall below 1 until the tile is removed from the cache.
* The dirty flag indicates whether the tile data has been dirtied
* while referenced.
*/
#if defined (TILE_DEBUG) && defined (__GNUC__)
#define tile_unref(t,d) _tile_unref (t, d, __PRETTY_FUNCTION__)
void _tile_unref (Tile *tile, int dirty, char *func_name);
#else
void tile_unref (Tile *tile, int dirty);
#endif
/* Allocate the data for the tile.
*/
void tile_alloc (Tile *tile);
/* Return the size in bytes of the tiles data.
*/
int tile_size (Tile *tile);
/* Invalidates a tile. This involves setting its invalid bit and
* a) if the tile is in memory deleting the tile data or b) if the
* tile is in the swap file, deleting the space it occupies. This
* will cause the tile data to need to be recalculated.
* This should probably only be used on sublevel tiles. Invalidating
* a toplevel tile would mean that it needs to be recalculated. But
* what do you recalculate a toplevel tile from?
*/
void tile_invalidate (Tile *tile);
#endif /* __TILE_H__ */