gimp/libgimp/gimptile.c

411 lines
10 KiB
C

/* LIBGIMP - The GIMP Library
* Copyright (C) 1995-1997 Peter Mattis and Spencer Kimball
*
* gimptile.c
*
* 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
* Library 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/>.
*/
#include "config.h"
#include <string.h>
#include <glib-object.h>
#define GIMP_DISABLE_DEPRECATION_WARNINGS
#include "libgimpbase/gimpbase.h"
#include "libgimpbase/gimpprotocol.h"
#include "libgimpbase/gimpwire.h"
#include "gimp.h"
/**
* SECTION: gimptile
* @title: gimptile
* @short_description: Functions for working with tiles.
*
* Functions for working with tiles.
**/
/* This is the percentage of the maximum cache size that
* should be cleared from the cache when an eviction is
* necessary.
*/
#define FREE_QUANTUM 0.1
void gimp_read_expect_msg (GimpWireMessage *msg,
gint type);
static void gimp_tile_get (GimpTile *tile);
static void gimp_tile_put (GimpTile *tile);
static void gimp_tile_cache_insert (GimpTile *tile);
static void gimp_tile_cache_flush (GimpTile *tile);
/* private variables */
static GHashTable * tile_hash_table = NULL;
static GList * tile_list_head = NULL;
static GList * tile_list_tail = NULL;
static gulong max_tile_size = 0;
static gulong cur_cache_size = 0;
static gulong max_cache_size = 0;
/* public functions */
void
gimp_tile_ref (GimpTile *tile)
{
g_return_if_fail (tile != NULL);
tile->ref_count++;
if (tile->ref_count == 1)
{
gimp_tile_get (tile);
tile->dirty = FALSE;
}
gimp_tile_cache_insert (tile);
}
void
gimp_tile_ref_zero (GimpTile *tile)
{
g_return_if_fail (tile != NULL);
tile->ref_count++;
if (tile->ref_count == 1)
tile->data = g_new0 (guchar, tile->ewidth * tile->eheight * tile->bpp);
gimp_tile_cache_insert (tile);
}
void
gimp_tile_unref (GimpTile *tile,
gboolean dirty)
{
g_return_if_fail (tile != NULL);
g_return_if_fail (tile->ref_count > 0);
tile->ref_count--;
tile->dirty |= dirty;
if (tile->ref_count == 0)
{
gimp_tile_flush (tile);
g_free (tile->data);
tile->data = NULL;
}
}
void
gimp_tile_flush (GimpTile *tile)
{
g_return_if_fail (tile != NULL);
if (tile->data && tile->dirty)
{
gimp_tile_put (tile);
tile->dirty = FALSE;
}
}
/**
* gimp_tile_cache_size:
* @kilobytes: new cache size in kilobytes
*
* Sets the size of the tile cache on the plug-in side. The tile cache
* is used to reduce the number of tiles exchanged between the GIMP core
* and the plug-in. See also gimp_tile_cache_ntiles().
**/
void
gimp_tile_cache_size (gulong kilobytes)
{
max_cache_size = kilobytes * 1024;
}
/**
* gimp_tile_cache_ntiles:
* @ntiles: number of tiles that should fit into the cache
*
* Sets the size of the tile cache on the plug-in side. This function
* is similar to gimp_tile_cache_size() but supports specifying the
* number of tiles directly.
*
* If your plug-in access pixels tile-by-tile, it doesn't need a tile
* cache at all. If however the plug-in accesses drawable pixel data
* row-by-row, it should set the tile cache large enough to hold the
* number of tiles per row. Double this size if your plug-in uses
* shadow tiles.
**/
void
gimp_tile_cache_ntiles (gulong ntiles)
{
gimp_tile_cache_size ((ntiles *
gimp_tile_width () *
gimp_tile_height () * 4 + 1023) / 1024);
}
void
_gimp_tile_cache_flush_drawable (GimpDrawable *drawable)
{
GList *list;
g_return_if_fail (drawable != NULL);
list = tile_list_head;
while (list)
{
GimpTile *tile = list->data;
list = list->next;
if (tile->drawable == drawable)
gimp_tile_cache_flush (tile);
}
}
/* private functions */
static void
gimp_tile_get (GimpTile *tile)
{
extern GIOChannel *_writechannel;
GPTileReq tile_req;
GPTileData *tile_data;
GimpWireMessage msg;
tile_req.drawable_ID = tile->drawable->drawable_id;
tile_req.tile_num = tile->tile_num;
tile_req.shadow = tile->shadow;
if (! gp_tile_req_write (_writechannel, &tile_req, NULL))
gimp_quit ();
gimp_read_expect_msg (&msg, GP_TILE_DATA);
tile_data = msg.data;
if (tile_data->drawable_ID != tile->drawable->drawable_id ||
tile_data->tile_num != tile->tile_num ||
tile_data->shadow != tile->shadow ||
tile_data->width != tile->ewidth ||
tile_data->height != tile->eheight ||
tile_data->bpp != tile->bpp)
{
g_message ("received tile info did not match computed tile info");
gimp_quit ();
}
if (tile_data->use_shm)
{
tile->data = g_memdup (gimp_shm_addr (),
tile->ewidth * tile->eheight * tile->bpp);
}
else
{
tile->data = tile_data->data;
tile_data->data = NULL;
}
if (! gp_tile_ack_write (_writechannel, NULL))
gimp_quit ();
gimp_wire_destroy (&msg);
}
static void
gimp_tile_put (GimpTile *tile)
{
extern GIOChannel *_writechannel;
GPTileReq tile_req;
GPTileData tile_data;
GPTileData *tile_info;
GimpWireMessage msg;
tile_req.drawable_ID = -1;
tile_req.tile_num = 0;
tile_req.shadow = 0;
if (! gp_tile_req_write (_writechannel, &tile_req, NULL))
gimp_quit ();
gimp_read_expect_msg (&msg, GP_TILE_DATA);
tile_info = msg.data;
tile_data.drawable_ID = tile->drawable->drawable_id;
tile_data.tile_num = tile->tile_num;
tile_data.shadow = tile->shadow;
tile_data.bpp = tile->bpp;
tile_data.width = tile->ewidth;
tile_data.height = tile->eheight;
tile_data.use_shm = tile_info->use_shm;
tile_data.data = NULL;
if (tile_info->use_shm)
memcpy (gimp_shm_addr (),
tile->data,
tile->ewidth * tile->eheight * tile->bpp);
else
tile_data.data = tile->data;
if (! gp_tile_data_write (_writechannel, &tile_data, NULL))
gimp_quit ();
if (! tile_info->use_shm)
tile_data.data = NULL;
gimp_wire_destroy (&msg);
gimp_read_expect_msg (&msg, GP_TILE_ACK);
gimp_wire_destroy (&msg);
}
/* This function is nearly identical to the function 'tile_cache_insert'
* in the file 'tile_cache.c' which is part of the main gimp application.
*/
static void
gimp_tile_cache_insert (GimpTile *tile)
{
GList *list;
if (!tile_hash_table)
{
tile_hash_table = g_hash_table_new (g_direct_hash, NULL);
max_tile_size = gimp_tile_width () * gimp_tile_height () * 4;
}
/* First check and see if the tile is already
* in the cache. In that case we will simply place
* it at the end of the tile list to indicate that
* it was the most recently accessed tile.
*/
list = g_hash_table_lookup (tile_hash_table, tile);
if (list)
{
/* The tile was already in the cache. Place it at
* the end of the tile list.
*/
/* If the tile is already at the end of the list, we are done */
if (list == tile_list_tail)
return;
/* At this point we have at least two elements in our list */
g_assert (tile_list_head != tile_list_tail);
tile_list_head = g_list_remove_link (tile_list_head, list);
tile_list_tail = g_list_last (g_list_concat (tile_list_tail, list));
}
else
{
/* The tile was not in the cache. First check and see
* if there is room in the cache. If not then we'll have
* to make room first. Note: it might be the case that the
* cache is smaller than the size of a tile in which case
* it won't be possible to put it in the cache.
*/
if ((cur_cache_size + max_tile_size) > max_cache_size)
{
while (tile_list_head &&
(cur_cache_size +
max_cache_size * FREE_QUANTUM) > max_cache_size)
{
gimp_tile_cache_flush ((GimpTile *) tile_list_head->data);
}
if ((cur_cache_size + max_tile_size) > max_cache_size)
return;
}
/* Place the tile at the end of the tile list.
*/
tile_list_tail = g_list_append (tile_list_tail, tile);
if (! tile_list_head)
tile_list_head = tile_list_tail;
tile_list_tail = g_list_last (tile_list_tail);
/* Add the tiles list node to the tile hash table.
*/
g_hash_table_insert (tile_hash_table, tile, tile_list_tail);
/* Note the increase in the number of bytes the cache
* is referencing.
*/
cur_cache_size += max_tile_size;
/* Reference the tile so that it won't be returned to
* the main gimp application immediately.
*/
tile->ref_count++;
}
}
static void
gimp_tile_cache_flush (GimpTile *tile)
{
GList *list;
if (! tile_hash_table)
return;
/* Find where the tile is in the cache.
*/
list = g_hash_table_lookup (tile_hash_table, tile);
if (list)
{
/* If the tile is in the cache, then remove it from the
* tile list.
*/
if (list == tile_list_tail)
tile_list_tail = tile_list_tail->prev;
tile_list_head = g_list_remove_link (tile_list_head, list);
if (! tile_list_head)
tile_list_tail = NULL;
/* Remove the tile from the tile hash table.
*/
g_hash_table_remove (tile_hash_table, tile);
g_list_free (list);
/* Note the decrease in the number of bytes the cache
* is referencing.
*/
cur_cache_size -= max_tile_size;
/* Unreference the tile.
*/
gimp_tile_unref (tile, FALSE);
}
}