gimp/app/core/gimppreviewcache.c

291 lines
6.5 KiB
C

/* GIMP - The GNU Image Manipulation Program
* Copyright (C) 1999 Andy Thomas alt@gimp.org
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 3 of the License, or
* (at your option) any later version.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include "config.h"
#include <glib-object.h>
#include "core-types.h"
#include "base/temp-buf.h"
#include "gimppreviewcache.h"
#define MAX_CACHE_PREVIEWS 5
typedef struct
{
TempBuf *buf;
gint width;
gint height;
} PreviewNearest;
static gint
preview_cache_compare (gconstpointer a,
gconstpointer b)
{
const TempBuf *buf1 = a;
const TempBuf *buf2 = b;
if (buf1->width > buf2->width && buf1->height > buf2->height)
return -1;
return 1;
}
static void
preview_cache_find_exact (gpointer data,
gpointer udata)
{
TempBuf *buf = data;
PreviewNearest *nearest = udata;
if (nearest->buf)
return;
if (buf->width == nearest->width && buf->height == nearest->height)
{
nearest->buf = buf;
return;
}
}
static void
preview_cache_find_biggest (gpointer data,
gpointer udata)
{
TempBuf *buf = data;
PreviewNearest *nearest = udata;
if (buf->width >= nearest->width && buf->height >= nearest->height)
{
/* Ok we could make the preview out of this one...
* If we already have it are these bigger dimensions?
*/
if (nearest->buf)
{
if (nearest->buf->width > buf->width &&
nearest->buf->height > buf->height)
return;
}
nearest->buf = buf;
}
}
static void
preview_cache_remove_smallest (GSList **plist)
{
GSList *list;
TempBuf *smallest = NULL;
#ifdef PREVIEW_CACHE_DEBUG
g_print ("preview_cache_remove_smallest\n");
#endif
for (list = *plist; list; list = list->next)
{
if (!smallest)
{
smallest = list->data;
}
else
{
TempBuf *this = list->data;
if (smallest->height * smallest->width > this->height * this->width)
{
smallest = this;
}
}
}
if (smallest)
{
*plist = g_slist_remove (*plist, smallest);
#ifdef PREVIEW_CACHE_DEBUG
g_print ("preview_cache_remove_smallest: removed %d x %d\n",
smallest->width, smallest->height);
#endif
temp_buf_free (smallest);
}
}
#ifdef PREVIEW_CACHE_DEBUG
static void
preview_cache_print (GSList *plist)
{
GSList *list;
g_print ("preview cache dump:\n");
for (list = plist; list; list = list->next)
{
TempBuf *buf = (TempBuf *) list->data;
g_print ("\tvalue w,h [%d,%d]\n", buf->width, buf->height);
}
}
#endif /* PREVIEW_CACHE_DEBUG */
void
gimp_preview_cache_invalidate (GSList **plist)
{
#ifdef PREVIEW_CACHE_DEBUG
g_print ("gimp_preview_cache_invalidate\n");
preview_cache_print (*plist);
#endif
g_slist_free_full (*plist, (GDestroyNotify) temp_buf_free);
*plist = NULL;
}
void
gimp_preview_cache_add (GSList **plist,
TempBuf *buf)
{
#ifdef PREVIEW_CACHE_DEBUG
g_print ("gimp_preview_cache_add: %d x %d\n", buf->width, buf->height);
preview_cache_print (*plist);
#endif
if (g_slist_length (*plist) >= MAX_CACHE_PREVIEWS)
{
preview_cache_remove_smallest (plist);
}
*plist = g_slist_insert_sorted (*plist, buf, preview_cache_compare);
}
TempBuf *
gimp_preview_cache_get (GSList **plist,
gint width,
gint height)
{
PreviewNearest pn;
#ifdef PREVIEW_CACHE_DEBUG
g_print ("gimp_preview_cache_get: %d x %d\n", width, height);
preview_cache_print (*plist);
#endif
pn.buf = NULL;
pn.width = width;
pn.height = height;
g_slist_foreach (*plist, preview_cache_find_exact, &pn);
if (pn.buf)
{
#ifdef PREVIEW_CACHE_DEBUG
g_print ("gimp_preview_cache_get: found exact match %d x %d\n",
pn.buf->width, pn.buf->height);
#endif
return pn.buf;
}
g_slist_foreach (*plist, preview_cache_find_biggest, &pn);
if (pn.buf)
{
TempBuf *preview;
gint pwidth;
gint pheight;
gdouble x_ratio;
gdouble y_ratio;
guchar *src_data;
guchar *dest_data;
gint loop1;
gint loop2;
#ifdef PREVIEW_CACHE_DEBUG
g_print ("gimp_preview_cache_get: nearest value: %d x %d\n",
pn.buf->width, pn.buf->height);
#endif
/* Make up new preview from the large one... */
pwidth = pn.buf->width;
pheight = pn.buf->height;
/* Now get the real one and add to cache */
preview = temp_buf_new (width, height, pn.buf->bytes, 0, 0, NULL);
/* preview from nearest bigger one */
if (width)
x_ratio = (gdouble) pwidth / (gdouble) width;
else
x_ratio = 0.0;
if (height)
y_ratio = (gdouble) pheight / (gdouble) height;
else
y_ratio = 0.0;
src_data = temp_buf_get_data (pn.buf);
dest_data = temp_buf_get_data (preview);
for (loop1 = 0 ; loop1 < height ; loop1++)
for (loop2 = 0 ; loop2 < width ; loop2++)
{
gint i;
guchar *src_pixel;
guchar *dest_pixel;
src_pixel = src_data +
((gint) (loop2 * x_ratio)) * preview->bytes +
((gint) (loop1 * y_ratio)) * pwidth * preview->bytes;
dest_pixel = dest_data +
(loop2 + loop1 * width) * preview->bytes;
for (i = 0; i < preview->bytes; i++)
*dest_pixel++ = *src_pixel++;
}
gimp_preview_cache_add (plist, preview);
return preview;
}
#ifdef PREVIEW_CACHE_DEBUG
g_print ("gimp_preview_cache_get returning NULL\n");
#endif
return NULL;
}
gsize
gimp_preview_cache_get_memsize (GSList *cache)
{
GSList *list;
gsize memsize = 0;
if (! cache)
return 0;
for (list = cache; list; list = list->next)
memsize += sizeof (GSList) + temp_buf_get_memsize ((TempBuf *) list->data);
return memsize;
}