1 // FGTileLoader - Queue scenery tiles for loading.
3 // Written by Bernie Bright, started March 2001.
5 // Copyright (C) 2001 Bernard Bright - bbright@bigpond.net.au
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.
27 #include <simgear/compiler.h>
28 #include <simgear/structure/exception.hxx>
30 #include <Main/globals.hxx>
31 #include "FGTileLoader.hxx"
32 #include "tileentry.hxx"
33 #include "tilemgr.hxx"
38 FGTileLoader::FGTileLoader()
40 #if defined(ENABLE_THREADS)
41 // Create and start the loader threads.
42 for (int i = 0; i < MAX_THREADS; ++i)
44 threads[i] = new LoaderThread(this);
45 threads[i]->start( 1 );
47 #endif // ENABLE_THREADS
51 * Terminate all threads.
53 FGTileLoader::~FGTileLoader()
55 #if defined(ENABLE_THREADS)
56 // Wake up its time to die.
57 // queue_cond.broadcast();
59 for (int i = 0; i < MAX_THREADS; ++i)
64 #endif // ENABLE_THREADS
68 #if 0 // we don't ever want to do this I don't think
72 void FGTileLoader::reinit() {
73 while ( !tile_load_queue.empty() ) {
74 tile_load_queue.pop();
84 FGTileLoader::add( FGTileEntry* tile )
87 * Initialise tile_path here and not in ctor to avoid problems
88 * with the initialisation order of global objects.
90 static bool beenhere = false;
92 tile_path = globals->get_fg_scenery();
93 if (!tile_path.size())
94 throw sg_throwable(string("No valid scenery path defined!"));
99 tile_load_queue.push( tile );
102 #ifdef WISH_PLIB_WAS_THREADED // but it isn't
107 FGTileLoader::remove( FGTileEntry* tile )
109 tile_free_queue.push( tile );
117 FGTileLoader::update()
120 #if defined(ENABLE_THREADS)
121 // send a signal to the pager thread that it is allowed to load
127 if ( !tile_load_queue.empty() ) {
128 // cout << "loading next tile ..." << endl;
129 // load the next tile in the queue
130 FGTileEntry* tile = tile_load_queue.front();
131 tile_load_queue.pop();
133 tile->load( tile_path, true );
135 FGTileMgr::ready_to_attach( tile );
138 #ifdef WISH_PLIB_WAS_THREADED // but it isn't
139 if ( !tile_free_queue.empty() ) {
140 // cout << "freeing next tile ..." << endl;
141 // free the next tile in the queue
142 FGTileEntry* tile = tile_free_queue.front();
143 tile_free_queue.pop();
149 #endif // ENABLE_THREADS
154 #if defined(ENABLE_THREADS)
156 * Ensure mutex is unlocked.
159 cleanup_handler( void* arg )
161 FGTileLoader* loader = (FGTileLoader*) arg;
162 loader->mutex.unlock();
169 FGTileLoader::LoaderThread::run()
171 pthread_cleanup_push( cleanup_handler, loader );
173 // Wait for a load request to be placed in the queue.
174 FGTileEntry* tile = loader->tile_load_queue.pop();
176 // Wait for the next frame signal before we load a tile from the queue
177 loader->mutex.lock();
178 loader->frame_cond.wait( loader->mutex );
179 loader->mutex.unlock();
181 set_cancel( SGThread::CANCEL_DISABLE );
182 tile->load( loader->tile_path, true );
183 set_cancel( SGThread::CANCEL_DEFERRED );
185 FGTileMgr::ready_to_attach( tile );
187 #ifdef WISH_PLIB_WAS_THREADED // but it isn't
188 // Handle and pending removals
189 while ( !loader->tile_free_queue.empty() ) {
190 // cout << "freeing next tile ..." << endl;
191 // free the next tile in the queue
192 FGTileEntry* tile = loader->tile_free_queue.pop();
199 pthread_cleanup_pop(1);
201 #endif // ENABLE_THREADS