1 // newcache.cxx -- routines to handle scenery tile caching
3 // Written by Curtis Olson, started December 2000.
5 // Copyright (C) 2000 Curtis L. Olson - http://www.flightgear.org/~curt
7 // This program is free software; you can redistribute it and/or
8 // modify it under the terms of the GNU General Public License as
9 // published by the Free Software Foundation; either version 2 of the
10 // License, or (at your option) any later version.
12 // This program is distributed in the hope that it will be useful, but
13 // WITHOUT ANY WARRANTY; without even the implied warranty of
14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 // General Public License for more details.
17 // You should have received a copy of the GNU General Public License
18 // along with this program; if not, write to the Free Software
19 // Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
24 # include <simgear_config.h>
27 #include <simgear/bucket/newbucket.hxx>
28 #include <simgear/debug/logstream.hxx>
29 #include <simgear/misc/sg_path.hxx>
31 #include "TileEntry.hxx"
32 #include "TileCache.hxx"
34 SG_USING_NAMESPACE(std);
36 using simgear::TileEntry;
37 using simgear::TileCache;
39 TileCache::TileCache( void ) :
46 TileCache::~TileCache( void ) {
51 // Free a tile cache entry
52 void TileCache::entry_free( long cache_index ) {
53 SG_LOG( SG_TERRAIN, SG_DEBUG, "FREEING CACHE ENTRY = " << cache_index );
54 TileEntry *tile = tile_cache[cache_index];
55 tile->removeFromSceneGraph();
60 tile_cache.erase( cache_index );
64 // Initialize the tile cache subsystem
65 void TileCache::init( void ) {
66 SG_LOG( SG_TERRAIN, SG_INFO, "Initializing the tile cache." );
68 SG_LOG( SG_TERRAIN, SG_INFO, " max cache size = "
70 SG_LOG( SG_TERRAIN, SG_INFO, " current cache size = "
71 << tile_cache.size() );
73 #if 0 // don't clear the cache
77 SG_LOG( SG_TERRAIN, SG_INFO, " done with init()" );
81 // Search for the specified "bucket" in the cache
82 bool TileCache::exists( const SGBucket& b ) const {
83 long tile_index = b.gen_index();
84 const_tile_map_iterator it = tile_cache.find( tile_index );
86 return ( it != tile_cache.end() );
90 // Return the index of the oldest tile in the cache, return -1 if
91 // nothing available to be removed.
92 long TileCache::get_oldest_tile() {
93 // we need to free the furthest entry
95 double timestamp = 0.0;
96 double min_time = DBL_MAX;
98 tile_map_iterator current = tile_cache.begin();
99 tile_map_iterator end = tile_cache.end();
101 for ( ; current != end; ++current ) {
102 long index = current->first;
103 TileEntry *e = current->second;
104 if ( e->is_loaded() ) {
105 timestamp = e->get_timestamp();
106 if ( timestamp < min_time ) {
107 min_time = timestamp;
111 SG_LOG( SG_TERRAIN, SG_DEBUG, "loaded = " << e->is_loaded()
112 << " time stamp = " << e->get_timestamp() );
116 SG_LOG( SG_TERRAIN, SG_DEBUG, " index = " << min_index );
117 SG_LOG( SG_TERRAIN, SG_DEBUG, " min_time = " << min_time );
123 // Clear the inner ring flag for all tiles in the cache so that the
124 // external tile scheduler can flag the inner ring correctly.
125 void TileCache::clear_inner_ring_flags() {
126 tile_map_iterator current = tile_cache.begin();
127 tile_map_iterator end = tile_cache.end();
129 for ( ; current != end; ++current ) {
130 TileEntry *e = current->second;
131 if ( e->is_loaded() ) {
132 e->set_inner_ring( false );
137 // Clear a cache entry, note that the cache only holds pointers
138 // and this does not free the object which is pointed to.
139 void TileCache::clear_entry( long cache_index ) {
140 tile_cache.erase( cache_index );
144 // Clear all completely loaded tiles (ignores partially loaded tiles)
145 void TileCache::clear_cache() {
146 std::vector<long> indexList;
147 tile_map_iterator current = tile_cache.begin();
148 tile_map_iterator end = tile_cache.end();
150 for ( ; current != end; ++current ) {
151 long index = current->first;
152 SG_LOG( SG_TERRAIN, SG_DEBUG, "clearing " << index );
153 TileEntry *e = current->second;
154 if ( e->is_loaded() ) {
155 e->tile_bucket.make_bad();
156 // entry_free modifies tile_cache, so store index and call entry_free() later;
157 indexList.push_back( index);
160 for (unsigned int it = 0; it < indexList.size(); it++) {
161 entry_free( indexList[ it]);
166 * Create a new tile and schedule it for loading.
168 bool TileCache::insert_tile( TileEntry *e ) {
169 // register tile in the cache
170 long tile_index = e->get_tile_bucket().gen_index();
171 tile_cache[tile_index] = e;