src/thumbnails.c

   1 /*
   2  * This program is free software; you can redistribute it and/or
   3  * modify it under the terms of the GNU General Public License
   4  * as published by the Free Software Foundation; either version 2
   5  * of the License, or (at your option) any later version.
   6  *
   7  * This program is distributed in the hope that it will be useful,
   8  * but WITHOUT ANY WARRANTY; without even the implied warranty of
   9  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  10  * GNU General Public License for more details.
  11  *
  12  * You should have received a copy of the GNU General Public License
  13  * along with this program; if not, write to the Free Software
  14  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  15  *
  16  * See the COPYING file for license information.
  17  *
  18  * Guillaume Chazarain <guichaz@yahoo.fr>
  19  */
  20
  21 /******************************************
  22  * Make thumbnails and keep track of them *
  23  ******************************************/
  24
  25 #include "gliv.h"
  26 #include "thumbnails.h"
  27 #include "options.h"
  28 #include "tree.h"
  29 #include "thread.h"
  30 #include "images_menus.h"
  31 #include "callbacks.h"
  32
  33 extern options_struct *options;
  34
  35 static GHashTable *thumbs_hash_table = NULL;
  36
  37 gchar *get_absolute_filename(const gchar * filename)
  38 {
  39     static gchar *cwd = NULL;
  40
  41     if (filename[0] == '/')
  42         return g_strdup(filename);
  43
  44     if (cwd == NULL)
  45         cwd = g_get_current_dir();
  46
  47     while (filename[0] == '.' && filename[1] == '/') {
  48         filename += 2;
  49         while (filename[0] == '/')
  50             filename++;
  51     }
  52
  53     return g_build_filename(cwd, filename, NULL);
  54 }
  55
  56 /*
  57  * We include the thumbnails wanted dimensions in the hash key, this way we can
  58  * keep track of many thumbnails with different sizes for a given filename.
  59  */
  60 static gchar *get_key(const gchar * filename)
  61 {
  62     gchar *key, *fullpath;
  63
  64     fullpath = get_absolute_filename(filename);
  65
  66     key = g_strdup_printf("%s_%d_%d", fullpath,
  67                           options->thumb_width, options->thumb_height);
  68     g_free(fullpath);
  69     return key;
  70 }
  71
  72 static GdkPixbuf *create_mini(GdkPixbuf * pixbuf)
  73 {
  74     gint w, h;
  75     gfloat zoom_w, zoom_h, zoom;
  76     gint mini_w, mini_h;
  77
  78     w = gdk_pixbuf_get_width(pixbuf);
  79     h = gdk_pixbuf_get_height(pixbuf);
  80
  81     zoom_w = (gfloat) w / options->thumb_width;
  82     zoom_h = (gfloat) h / options->thumb_height;
  83     zoom = MAX(zoom_w, zoom_h);
  84
  85     if (zoom <= 1.0)
  86         /* A thumbnail should not be bigger than the original. */
  87         return pixbuf;
  88
  89     mini_w = (gint) (w / zoom);
  90     mini_h = (gint) (h / zoom);
  91
  92     mini_w = MAX(mini_w, 1);
  93     mini_h = MAX(mini_h, 1);
  94
  95     return gdk_pixbuf_scale_simple(pixbuf, mini_w, mini_h, GDK_INTERP_BILINEAR);
  96 }
  97
  98 static void init_hash(void)
  99 {
 100     if (thumbs_hash_table == NULL)
 101         /* First time. */
 102         thumbs_hash_table = g_hash_table_new(g_str_hash, g_str_equal);
 103 }
 104
 105 /* Runs in a separate thread. */
 106 static GdkPixbuf *get_mini(tree_item * item)
 107 {
 108     GdkPixbuf *pixbuf, *mini;
 109
 110     if (canceled_using_tree())
 111         return NULL;
 112
 113     init_hash();
 114
 115     mini = g_hash_table_lookup(thumbs_hash_table, item->thumb_key);
 116     if (mini != NULL)
 117         return mini;
 118
 119     pixbuf = gdk_pixbuf_new_from_file(item->path, NULL);
 120     if (pixbuf == NULL)
 121         return NULL;
 122
 123     if (canceled_using_tree()) {
 124         g_object_unref(pixbuf);
 125         return NULL;
 126     }
 127
 128     mini = create_mini(pixbuf);
 129     if (mini != pixbuf)
 130         g_object_unref(pixbuf);
 131
 132     g_hash_table_insert(thumbs_hash_table, item->thumb_key, mini);
 133
 134     if (canceled_using_tree())
 135         mini = NULL;
 136
 137     return mini;
 138 }
 139
 140 gboolean fill_thumbnail(tree_item * item)
 141 {
 142     if (item->thumb == NULL) {
 143         if (item->thumb_key == NULL)
 144             item->thumb_key = get_key(item->path);
 145
 146         item->thumb = do_threaded((GThreadFunc) get_mini, item);
 147         return item->thumb != NULL;
 148     } else
 149         /* Simulate the do_threaded() effect. */
 150         process_events();
 151
 152     return TRUE;
 153 }
 154
 155 void collection_add_thumbnail(gchar * key, GdkPixbuf * thumb)
 156 {
 157     init_hash();
 158
 159     g_hash_table_insert(thumbs_hash_table, key, thumb);
 160 }