1 // newcache.cxx -- routines to handle scenery tile caching
3 // Written by Curtis Olson, started December 2000.
5 // Copyright (C) 2000 Curtis L. Olson - curt@flightgear.org
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., 675 Mass Ave, Cambridge, MA 02139, USA.
35 #include <plib/ssg.h> // plib include
37 #include <simgear/bucket/newbucket.hxx>
38 #include <simgear/debug/logstream.hxx>
39 #include <simgear/misc/sg_path.hxx>
41 #include <Main/globals.hxx>
42 #include <Main/viewer.hxx>
43 #include <Scenery/scenery.hxx> // for scenery.center
45 #include "newcache.hxx"
46 #include "tileentry.hxx"
49 SG_USING_NAMESPACE(std);
53 FGNewCache::FGNewCache( void ) :
61 FGNewCache::~FGNewCache( void ) {
65 // Free a tile cache entry
66 void FGNewCache::entry_free( long cache_index ) {
67 SG_LOG( SG_TERRAIN, SG_DEBUG, "FREEING CACHE ENTRY = " << cache_index );
68 FGTileEntry *tile = tile_cache[cache_index];
69 tile->disconnect_ssg_nodes();
71 #ifdef WISH_PLIB_WAS_THREADED // but it isn't
72 tile->sched_removal();
78 tile_cache.erase( cache_index );
82 // Initialize the tile cache subsystem
83 void FGNewCache::init( void ) {
84 SG_LOG( SG_TERRAIN, SG_INFO, "Initializing the tile cache." );
86 SG_LOG( SG_TERRAIN, SG_INFO, " max cache size = "
88 SG_LOG( SG_TERRAIN, SG_INFO, " current cache size = "
89 << tile_cache.size() );
91 #if 0 // don't clear the cache
95 SG_LOG( SG_TERRAIN, SG_INFO, " done with init()" );
99 // Search for the specified "bucket" in the cache
100 bool FGNewCache::exists( const SGBucket& b ) const {
101 long tile_index = b.gen_index();
102 const_tile_map_iterator it = tile_cache.find( tile_index );
104 return ( it != tile_cache.end() );
109 // Ensure at least one entry is free in the cache
110 bool FGNewCache::make_space() {
111 SG_LOG( SG_TERRAIN, SG_DEBUG, "Make space in cache" );
112 SG_LOG( SG_TERRAIN, SG_DEBUG, "cache entries = " << tile_cache.size() );
113 SG_LOG( SG_TERRAIN, SG_DEBUG, "max size = " << max_cache_size );
115 if ( (int)tile_cache.size() < max_cache_size ) {
116 // space in the cache, return
120 while ( (int)tile_cache.size() >= max_cache_size ) {
121 sgdVec3 abs_view_pos;
123 double timestamp = 0.0;
125 double min_time = 2419200000.0f; // one month should be enough
128 // we need to free the furthest entry
129 tile_map_iterator current = tile_cache.begin();
130 tile_map_iterator end = tile_cache.end();
132 for ( ; current != end; ++current ) {
133 long index = current->first;
134 FGTileEntry *e = current->second;
135 if ( e->is_loaded() && (e->get_pending_models() == 0) ) {
137 timestamp = e->get_timestamp();
138 if ( timestamp < min_time ) {
140 min_time = timestamp;
142 if ( timestamp > max_time ) {
143 max_time = timestamp;
147 SG_LOG( SG_TERRAIN, SG_DEBUG, "loaded = " << e->is_loaded()
148 << " pending models = " << e->get_pending_models()
149 << " time stamp = " << e->get_timestamp() );
153 // If we made it this far, then there were no open cache entries.
154 // We will instead free the oldest cache entry and return true
156 SG_LOG( SG_TERRAIN, SG_DEBUG, " min_time = " << min_time );
157 SG_LOG( SG_TERRAIN, SG_DEBUG, " index = " << max_index );
158 SG_LOG( SG_TERRAIN, SG_DEBUG, " max_time = " << max_time );
159 if ( max_index >= 0 ) {
160 entry_free( max_index );
163 SG_LOG( SG_TERRAIN, SG_ALERT, "WHOOPS!!! can't make_space(), tile "
164 "cache is full, but no entries available for removal." );
169 SG_LOG( SG_TERRAIN, SG_ALERT, "WHOOPS!!! Hit an unhandled condition in "
170 "FGNewCache::make_space()." );
176 // Return the index of the oldest tile in the cache, return -1 if
177 // nothing available to be removed.
178 long FGNewCache::get_oldest_tile() {
179 // we need to free the furthest entry
181 double timestamp = 0.0;
182 double min_time = 2419200000.0f; // one month should be enough
185 tile_map_iterator current = tile_cache.begin();
186 tile_map_iterator end = tile_cache.end();
188 for ( ; current != end; ++current ) {
189 long index = current->first;
190 FGTileEntry *e = current->second;
191 if ( e->is_loaded() && (e->get_pending_models() == 0) ) {
193 timestamp = e->get_timestamp();
194 if ( timestamp < min_time ) {
196 min_time = timestamp;
198 if ( timestamp > max_time ) {
199 max_time = timestamp;
203 SG_LOG( SG_TERRAIN, SG_DEBUG, "loaded = " << e->is_loaded()
204 << " pending models = " << e->get_pending_models()
205 << " time stamp = " << e->get_timestamp() );
209 SG_LOG( SG_TERRAIN, SG_DEBUG, " min_time = " << min_time );
210 SG_LOG( SG_TERRAIN, SG_DEBUG, " index = " << min_index );
211 SG_LOG( SG_TERRAIN, SG_DEBUG, " max_time = " << max_time );
217 // Clear a cache entry, note that the cache only holds pointers
218 // and this does not free the object which is pointed to.
219 void FGNewCache::clear_entry( long cache_index ) {
220 tile_cache.erase( cache_index );
224 // Clear all completely loaded tiles (ignores partially loaded tiles)
225 void FGNewCache::clear_cache() {
227 tile_map_iterator current = tile_cache.begin();
228 tile_map_iterator end = tile_cache.end();
230 for ( ; current != end; ++current ) {
231 long index = current->first;
232 SG_LOG( SG_TERRAIN, SG_DEBUG, "clearing " << index );
233 FGTileEntry *e = current->second;
234 if ( e->is_loaded() && (e->get_pending_models() == 0) ) {
235 e->tile_bucket.make_bad();
240 // and ... just in case we missed something ...
241 globals->get_scenery()->get_terrain_branch()->removeAllKids();
246 * Create a new tile and schedule it for loading.
248 bool FGNewCache::insert_tile( FGTileEntry *e ) {
249 // set time of insertion for tracking age of tiles...
250 e->set_timestamp(globals->get_sim_time_sec());
252 // register it in the cache
253 long tile_index = e->get_tile_bucket().gen_index();
254 tile_cache[tile_index] = e;
260 // Note this is the old version of FGNewCache::make_space(), currently disabled
261 // It uses distance from a center point to determine tiles to be discarded...
263 // Ensure at least one entry is free in the cache
264 bool FGNewCache::make_space() {
265 SG_LOG( SG_TERRAIN, SG_DEBUG, "Make space in cache" );
266 SG_LOG( SG_TERRAIN, SG_DEBUG, "cache entries = " << tile_cache.size() );
267 SG_LOG( SG_TERRAIN, SG_DEBUG, "max size = " << max_cache_size );
269 if ( (int)tile_cache.size() < max_cache_size ) {
270 // space in the cache, return
274 while ( (int)tile_cache.size() >= max_cache_size ) {
275 sgdVec3 abs_view_pos;
277 float max_dist = 0.0;
280 // we need to free the furthest entry
281 tile_map_iterator current = tile_cache.begin();
282 tile_map_iterator end = tile_cache.end();
284 for ( ; current != end; ++current ) {
285 long index = current->first;
286 FGTileEntry *e = current->second;
288 if ( e->is_loaded() && (e->get_pending_models() == 0) ) {
289 // calculate approximate distance from view point
290 sgdCopyVec3( abs_view_pos,
291 globals->get_current_view()->get_absolute_view_pos() );
293 SG_LOG( SG_TERRAIN, SG_DEBUG, "DIST Abs view pos = "
294 << abs_view_pos[0] << ","
295 << abs_view_pos[1] << ","
296 << abs_view_pos[2] );
297 SG_LOG( SG_TERRAIN, SG_DEBUG,
298 " ref point = " << e->center );
302 e->center.x(), e->center.y(), e->center.z() );
303 dist = sgdDistanceVec3( center, abs_view_pos );
305 SG_LOG( SG_TERRAIN, SG_DEBUG, " distance = " << dist );
307 if ( dist > max_dist ) {
312 SG_LOG( SG_TERRAIN, SG_INFO, "loaded = " << e->is_loaded()
313 << " pending models = " << e->get_pending_models() );
317 // If we made it this far, then there were no open cache entries.
318 // We will instead free the furthest cache entry and return true
320 SG_LOG( SG_TERRAIN, SG_INFO, " max_dist = " << max_dist );
321 SG_LOG( SG_TERRAIN, SG_INFO, " index = " << max_index );
322 if ( max_index >= 0 ) {
323 entry_free( max_index );
326 SG_LOG( SG_TERRAIN, SG_ALERT, "WHOOPS!!! can't make_space(), tile "
327 "cache is full, but no entries available for removal." );
332 SG_LOG( SG_TERRAIN, SG_ALERT, "WHOOPS!!! Hit an unhandled condition in "
333 "FGNewCache::make_space()." );