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.
23 #include <simgear/bucket/newbucket.hxx>
24 #include <simgear/debug/logstream.hxx>
25 #include <simgear/misc/sg_path.hxx>
27 #include "TileEntry.hxx"
28 #include "TileCache.hxx"
30 SG_USING_NAMESPACE(std);
32 using simgear::TileEntry;
33 using simgear::TileCache;
35 TileCache::TileCache( void ) :
42 TileCache::~TileCache( void ) {
47 // Free a tile cache entry
48 void TileCache::entry_free( long cache_index ) {
49 SG_LOG( SG_TERRAIN, SG_DEBUG, "FREEING CACHE ENTRY = " << cache_index );
50 TileEntry *tile = tile_cache[cache_index];
51 tile->removeFromSceneGraph();
56 tile_cache.erase( cache_index );
60 // Initialize the tile cache subsystem
61 void TileCache::init( void ) {
62 SG_LOG( SG_TERRAIN, SG_INFO, "Initializing the tile cache." );
64 SG_LOG( SG_TERRAIN, SG_INFO, " max cache size = "
66 SG_LOG( SG_TERRAIN, SG_INFO, " current cache size = "
67 << tile_cache.size() );
69 #if 0 // don't clear the cache
73 SG_LOG( SG_TERRAIN, SG_INFO, " done with init()" );
77 // Search for the specified "bucket" in the cache
78 bool TileCache::exists( const SGBucket& b ) const {
79 long tile_index = b.gen_index();
80 const_tile_map_iterator it = tile_cache.find( tile_index );
82 return ( it != tile_cache.end() );
86 // Return the index of the oldest tile in the cache, return -1 if
87 // nothing available to be removed.
88 long TileCache::get_oldest_tile() {
89 // we need to free the furthest entry
91 double timestamp = 0.0;
92 double min_time = DBL_MAX;
94 tile_map_iterator current = tile_cache.begin();
95 tile_map_iterator end = tile_cache.end();
97 for ( ; current != end; ++current ) {
98 long index = current->first;
99 TileEntry *e = current->second;
100 if ( e->is_loaded() ) {
101 timestamp = e->get_timestamp();
102 if ( timestamp < min_time ) {
103 min_time = timestamp;
107 SG_LOG( SG_TERRAIN, SG_DEBUG, "loaded = " << e->is_loaded()
108 << " time stamp = " << e->get_timestamp() );
112 SG_LOG( SG_TERRAIN, SG_DEBUG, " index = " << min_index );
113 SG_LOG( SG_TERRAIN, SG_DEBUG, " min_time = " << min_time );
119 // Clear the inner ring flag for all tiles in the cache so that the
120 // external tile scheduler can flag the inner ring correctly.
121 void TileCache::clear_inner_ring_flags() {
122 tile_map_iterator current = tile_cache.begin();
123 tile_map_iterator end = tile_cache.end();
125 for ( ; current != end; ++current ) {
126 TileEntry *e = current->second;
127 if ( e->is_loaded() ) {
128 e->set_inner_ring( false );
133 // Clear a cache entry, note that the cache only holds pointers
134 // and this does not free the object which is pointed to.
135 void TileCache::clear_entry( long cache_index ) {
136 tile_cache.erase( cache_index );
140 // Clear all completely loaded tiles (ignores partially loaded tiles)
141 void TileCache::clear_cache() {
142 std::vector<long> indexList;
143 tile_map_iterator current = tile_cache.begin();
144 tile_map_iterator end = tile_cache.end();
146 for ( ; current != end; ++current ) {
147 long index = current->first;
148 SG_LOG( SG_TERRAIN, SG_DEBUG, "clearing " << index );
149 TileEntry *e = current->second;
150 if ( e->is_loaded() ) {
151 e->tile_bucket.make_bad();
152 // entry_free modifies tile_cache, so store index and call entry_free() later;
153 indexList.push_back( index);
156 for (unsigned int it = 0; it < indexList.size(); it++) {
157 entry_free( indexList[ it]);
162 * Create a new tile and schedule it for loading.
164 bool TileCache::insert_tile( TileEntry *e ) {
165 // register tile in the cache
166 long tile_index = e->get_tile_bucket().gen_index();
167 tile_cache[tile_index] = e;