2 * viking -- GPS Data and Topo Analyzer, Explorer, and Manager
4 * Copyright (C) 2003-2005, Evan Battaglia <gtoevan@gmx.net>
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
26 #include <glib/gi18n.h>
30 #include "preferences.h"
31 #include "vik_compat.h"
33 typedef struct _List {
38 /* a circular linked list, a pointer to the tail, and the tail points to the head */
39 /* this is so we can free the last */
40 static List *queue_tail = NULL;
41 static int queue_count = 0;
43 static guint32 cache_size = 0;
44 static guint32 max_cache_size = VIK_CONFIG_MAPCACHE_SIZE * 1024 * 1024;
46 static GHashTable *cache = NULL;
48 static GMutex *mc_mutex = NULL;
50 #define HASHKEY_FORMAT_STRING "%d-%d-%d-%d-%d-%d-%d-%.3f-%.3f"
51 #define HASHKEY_FORMAT_STRING_NOSHRINK_NOR_ALPHA "%d-%d-%d-%d-%d-%d-"
53 static VikLayerParamScale params_scales[] = {
54 /* min, max, step, digits (decimal places) */
58 static VikLayerParam prefs[] = {
59 { VIK_LAYER_NUM_TYPES, VIKING_PREFERENCES_NAMESPACE "mapcache_size", VIK_LAYER_PARAM_UINT, VIK_LAYER_GROUP_NONE, N_("Map cache memory size (MB):"), VIK_LAYER_WIDGET_HSCALE, params_scales, NULL, NULL, NULL, NULL, NULL },
62 void a_mapcache_init ()
64 VikLayerParamData tmp;
65 tmp.u = VIK_CONFIG_MAPCACHE_SIZE;
66 a_preferences_register(prefs, tmp, VIKING_PREFERENCES_GROUP_KEY);
68 mc_mutex = vik_mutex_new ();
69 cache = g_hash_table_new_full ( g_str_hash, g_str_equal, g_free, g_object_unref );
72 static void cache_add(gchar *key, GdkPixbuf *pixbuf)
74 #if !GLIB_CHECK_VERSION(2,26,0)
75 // Only later versions of GLib actually return a value for this function
76 // Annoyingly the documentation doesn't say anything about this interface change :(
77 if ( g_hash_table_insert ( cache, key, pixbuf ) )
79 g_hash_table_insert ( cache, key, pixbuf );
82 cache_size += gdk_pixbuf_get_rowstride(pixbuf) * gdk_pixbuf_get_height(pixbuf);
87 static void cache_remove(const gchar *key)
89 GdkPixbuf *buf = g_hash_table_lookup ( cache, key );
91 cache_size -= gdk_pixbuf_get_rowstride(buf) * gdk_pixbuf_get_height(buf);
93 g_hash_table_remove ( cache, key );
97 /* returns key from head, adds on newtailkey to tail. */
98 static gchar *list_shift_add_entry ( gchar *newtailkey )
100 gchar *oldheadkey = queue_tail->next->key;
101 queue_tail->next->key = newtailkey;
102 queue_tail = queue_tail->next;
106 static gchar *list_shift ()
108 gchar *oldheadkey = queue_tail->next->key;
109 List *oldhead = queue_tail->next;
110 queue_tail->next = queue_tail->next->next;
116 /* adds key to tail */
117 static void list_add_entry ( gchar *key )
119 List *newlist = g_malloc ( sizeof ( List ) );
122 newlist->next = queue_tail->next;
123 queue_tail->next = newlist;
124 queue_tail = newlist;
126 newlist->next = newlist;
127 queue_tail = newlist;
132 void a_mapcache_add ( GdkPixbuf *pixbuf, gint x, gint y, gint z, guint16 type, gint zoom, guint8 alpha, gdouble xshrinkfactor, gdouble yshrinkfactor, const gchar* name )
134 guint nn = name ? g_str_hash ( name ) : 0;
135 gchar *key = g_strdup_printf ( HASHKEY_FORMAT_STRING, x, y, z, type, zoom, nn, alpha, xshrinkfactor, yshrinkfactor );
137 g_mutex_lock(mc_mutex);
138 cache_add(key, pixbuf);
140 // TODO: that should be done on preference change only...
141 max_cache_size = a_preferences_get(VIKING_PREFERENCES_NAMESPACE "mapcache_size")->u * 1024 * 1024;
143 if ( cache_size > max_cache_size ) {
145 gchar *oldkey = list_shift_add_entry ( key );
146 cache_remove(oldkey);
148 while ( cache_size > max_cache_size &&
149 (queue_tail->next != queue_tail) ) { /* make sure there's more than one thing to delete */
150 oldkey = list_shift ();
151 cache_remove(oldkey);
154 /* chop off 'start' etc */
156 list_add_entry ( key );
157 /* business as usual */
159 g_mutex_unlock(mc_mutex);
162 if ( (++tmp == 100 )) { g_debug("DEBUG: cache count=%d size=%u list count=%d\n", g_hash_table_size(cache), cache_size, queue_count ); tmp=0; }
165 GdkPixbuf *a_mapcache_get ( gint x, gint y, gint z, guint16 type, gint zoom, guint8 alpha, gdouble xshrinkfactor, gdouble yshrinkfactor, const gchar* name )
168 guint nn = name ? g_str_hash ( name ) : 0;
169 g_snprintf ( key, sizeof(key), HASHKEY_FORMAT_STRING, x, y, z, type, zoom, nn, alpha, xshrinkfactor, yshrinkfactor );
170 return g_hash_table_lookup ( cache, key );
174 * Appears this is only used when redownloading tiles (i.e. to invalidate old images)
176 void a_mapcache_remove_all_shrinkfactors ( gint x, gint y, gint z, guint16 type, gint zoom )
179 List *loop = queue_tail;
183 if ( queue_tail == NULL )
186 g_snprintf ( key, sizeof(key), HASHKEY_FORMAT_STRING_NOSHRINK_NOR_ALPHA, x, y, z, type, zoom, 0 );
189 g_mutex_lock(mc_mutex);
190 /* TODO: check logic here */
194 if ( strncmp(tmp->key, key, len) == 0 )
196 cache_remove(tmp->key);
197 if ( tmp == loop ) /* we deleted the last thing in the queue! */
198 loop = queue_tail = NULL;
200 loop->next = tmp->next;
201 if ( tmp == queue_tail )
202 queue_tail = tmp->next;
212 } while ( loop && (loop != queue_tail || tmp == NULL) );
214 /* loop thru list, looking for the one, compare first whatever chars */
216 g_mutex_unlock(mc_mutex);
219 void a_mapcache_flush ()
221 List *loop = queue_tail;
224 if ( queue_tail == NULL )
227 g_mutex_lock(mc_mutex);
230 cache_remove(tmp->key);
231 if ( tmp == queue_tail ) /* we deleted the last thing in the queue */
232 loop = queue_tail = NULL;
234 loop->next = tmp->next;
239 g_mutex_unlock(mc_mutex);
242 void a_mapcache_uninit ()
244 g_hash_table_destroy ( cache );
247 vik_mutex_free (mc_mutex);
250 // Size of mapcache in memory
251 gint a_mapcache_get_size ()
256 // Count of items in the mapcache
257 gint a_mapcache_get_count ()
259 return g_hash_table_size ( cache );