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() );
108 // Ensure at least one entry is free in the cache
109 bool FGNewCache::make_space() {
110 SG_LOG( SG_TERRAIN, SG_DEBUG, "Make space in cache" );
111 SG_LOG( SG_TERRAIN, SG_DEBUG, "cache entries = " << tile_cache.size() );
112 SG_LOG( SG_TERRAIN, SG_DEBUG, "max size = " << max_cache_size );
114 if ( (int)tile_cache.size() < max_cache_size ) {
115 // space in the cache, return
119 while ( (int)tile_cache.size() >= max_cache_size ) {
120 sgdVec3 abs_view_pos;
122 float max_dist = 0.0;
125 // we need to free the furthest entry
126 tile_map_iterator current = tile_cache.begin();
127 tile_map_iterator end = tile_cache.end();
129 for ( ; current != end; ++current ) {
130 long index = current->first;
131 FGTileEntry *e = current->second;
133 if ( e->is_loaded() && (e->get_pending_models() == 0) ) {
134 // calculate approximate distance from view point
135 sgdCopyVec3( abs_view_pos,
136 globals->get_current_view()->get_absolute_view_pos() );
138 SG_LOG( SG_TERRAIN, SG_DEBUG, "DIST Abs view pos = "
139 << abs_view_pos[0] << ","
140 << abs_view_pos[1] << ","
141 << abs_view_pos[2] );
142 SG_LOG( SG_TERRAIN, SG_DEBUG,
143 " ref point = " << e->center );
147 e->center.x(), e->center.y(), e->center.z() );
148 dist = sgdDistanceVec3( center, abs_view_pos );
150 SG_LOG( SG_TERRAIN, SG_DEBUG, " distance = " << dist );
152 if ( dist > max_dist ) {
157 SG_LOG( SG_TERRAIN, SG_INFO, "loaded = " << e->is_loaded()
158 << " pending models = " << e->get_pending_models() );
162 // If we made it this far, then there were no open cache entries.
163 // We will instead free the furthest cache entry and return true
165 SG_LOG( SG_TERRAIN, SG_INFO, " max_dist = " << max_dist );
166 SG_LOG( SG_TERRAIN, SG_INFO, " index = " << max_index );
167 if ( max_index >= 0 ) {
168 entry_free( max_index );
171 SG_LOG( SG_TERRAIN, SG_ALERT, "WHOOPS!!! can't make_space(), tile "
172 "cache is full, but no entries available for removal." );
177 SG_LOG( SG_TERRAIN, SG_ALERT, "WHOOPS!!! Hit an unhandled condition in "
178 "FGNewCache::make_space()." );
183 // Clear all completely loaded tiles (ignores partially loaded tiles)
184 void FGNewCache::clear_cache() {
185 // This is a hack that should really get cleaned up at some point
186 extern ssgBranch *terrain_branch;
188 tile_map_iterator current = tile_cache.begin();
189 tile_map_iterator end = tile_cache.end();
191 for ( ; current != end; ++current ) {
192 long index = current->first;
193 SG_LOG( SG_TERRAIN, SG_DEBUG, "clearing " << index );
194 FGTileEntry *e = current->second;
195 if ( e->is_loaded() && (e->get_pending_models() == 0) ) {
196 e->tile_bucket.make_bad();
201 // and ... just in case we missed something ...
202 terrain_branch->removeAllKids();
207 * Create a new tile and schedule it for loading.
209 bool FGNewCache::insert_tile( FGTileEntry *e ) {
210 // clear out a distant entry in the cache if needed.
211 if ( make_space() ) {
212 // register it in the cache
213 long tile_index = e->get_tile_bucket().gen_index();
214 tile_cache[tile_index] = e;
218 // failed to find cache space