1 // tilecache.cxx -- routines to handle scenery tile caching
3 // Written by Curtis Olson, started January 1998.
5 // Copyright (C) 1997 Curtis L. Olson - curt@infoplane.com
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.
22 // (Log is kept at end of this file)
36 #include <Bucket/bucketutils.h>
37 #include <Debug/fg_debug.h>
38 #include <Main/options.hxx>
39 #include <Main/views.hxx>
40 #include <Objects/obj.hxx>
43 #include "tilecache.hxx"
47 fgTILECACHE global_tile_cache;
51 fgTILECACHE::fgTILECACHE( void ) {
55 // Initialize the tile cache subsystem
56 void fgTILECACHE::Init( void ) {
59 fgPrintf(FG_TERRAIN, FG_INFO, "Initializing the tile cache.\n");
61 for ( i = 0; i < FG_TILE_CACHE_SIZE; i++ ) {
62 tile_cache[i].used = 0;
67 // Search for the specified "bucket" in the cache
68 int fgTILECACHE::Exists( fgBUCKET *p ) {
71 for ( i = 0; i < FG_TILE_CACHE_SIZE; i++ ) {
72 if ( tile_cache[i].tile_bucket.lon == p->lon ) {
73 if ( tile_cache[i].tile_bucket.lat == p->lat ) {
74 if ( tile_cache[i].tile_bucket.x == p->x ) {
75 if ( tile_cache[i].tile_bucket.y == p->y ) {
76 fgPrintf( FG_TERRAIN, FG_DEBUG,
77 "TILE EXISTS in cache ... index = %d\n", i );
89 // Fill in a tile cache entry with real data for the specified bucket
90 void fgTILECACHE::EntryFillIn( int index, fgBUCKET *p ) {
95 // Mark this cache entry as used
96 tile_cache[index].used = 1;
99 tile_cache[index].tile_bucket.lon = p->lon;
100 tile_cache[index].tile_bucket.lat = p->lat;
101 tile_cache[index].tile_bucket.x = p->x;
102 tile_cache[index].tile_bucket.y = p->y;
104 // Load the appropriate data file and built tile fragment list
105 fgBucketGenBasePath(p, base_path);
106 root = current_options.get_fg_root();
107 sprintf(file_name, "%s/Scenery/%s/%ld", root.c_str(),
108 base_path, fgBucketGenIndex(p));
109 fgObjLoad(file_name, &tile_cache[index]);
111 tile_cache[index].display_list =
112 fgObjLoad(file_name, &tile_cache[index].local_ref,
113 &tile_cache[index].bounding_radius);
118 // Free a tile cache entry
119 void fgTILECACHE::EntryFree( int index ) {
120 fgFRAGMENT *fragment;
122 // Mark this cache entry as un-used
123 tile_cache[index].used = 0;
126 fgPrintf( FG_TERRAIN, FG_DEBUG,
127 "FREEING TILE = (%d %d %d %d)\n",
128 tile_cache[index].tile_bucket.lon,
129 tile_cache[index].tile_bucket.lat,
130 tile_cache[index].tile_bucket.x,
131 tile_cache[index].tile_bucket.y );
133 // Step through the fragment list, deleting the display list, then
134 // the fragment, until the list is empty.
135 while ( tile_cache[index].fragment_list.size() ) {
136 list < fgFRAGMENT > :: iterator current =
137 tile_cache[index].fragment_list.begin();
138 fragment = &(*current);
139 xglDeleteLists( fragment->display_list, 1 );
141 tile_cache[index].fragment_list.pop_front();
146 // Return the specified tile cache entry
147 fgTILE *fgTILECACHE::GetTile( int index ) {
148 return ( &tile_cache[index] );
152 // Return index of next available slot in tile cache
153 int fgTILECACHE::NextAvail( void ) {
156 float dx, dy, dz, max, med, min, tmp;
157 float dist, max_dist;
165 for ( i = 0; i < FG_TILE_CACHE_SIZE; i++ ) {
166 if ( tile_cache[i].used == 0 ) {
169 // calculate approximate distance from view point
170 fgPrintf( FG_TERRAIN, FG_DEBUG,
171 "DIST Abs view pos = %.4f, %.4f, %.4f\n",
172 v->abs_view_pos.x, v->abs_view_pos.y, v->abs_view_pos.z );
173 fgPrintf( FG_TERRAIN, FG_DEBUG,
174 " ref point = %.4f, %.4f, %.4f\n",
175 tile_cache[i].center.x, tile_cache[i].center.y,
176 tile_cache[i].center.z);
178 dx = fabs(tile_cache[i].center.x - v->abs_view_pos.x);
179 dy = fabs(tile_cache[i].center.y - v->abs_view_pos.y);
180 dz = fabs(tile_cache[i].center.z - v->abs_view_pos.z);
182 max = dx; med = dy; min = dz;
184 tmp = max; max = med; med = tmp;
187 tmp = max; max = min; min = tmp;
189 dist = max + (med + min) / 4;
191 fgPrintf( FG_TERRAIN, FG_DEBUG, " distance = %.2f\n", dist);
193 if ( dist > max_dist ) {
200 // If we made it this far, then there were no open cache entries.
201 // We will instead free the furthest cache entry and return it's
204 EntryFree( max_index );
210 fgTILECACHE::~fgTILECACHE( void ) {
215 // Revision 1.15 1998/08/27 17:02:10 curt
216 // Contributions from Bernie Bright <bbright@c031.aone.net.au>
217 // - use strings for fg_root and airport_id and added methods to return
219 // - inlined all access methods,
220 // - made the parsing functions private methods,
221 // - deleted some unused functions.
222 // - propogated some of these changes out a bit further.
224 // Revision 1.14 1998/08/25 16:52:43 curt
225 // material.cxx material.hxx obj.cxx obj.hxx texload.c texload.h moved to
228 // Revision 1.13 1998/07/13 21:02:00 curt
229 // Wrote access functions for current fgOPTIONS.
231 // Revision 1.12 1998/07/12 03:18:29 curt
232 // Added ground collision detection. This involved:
233 // - saving the entire vertex list for each tile with the tile records.
234 // - saving the face list for each fragment with the fragment records.
235 // - code to intersect the current vertical line with the proper face in
236 // an efficient manner as possible.
237 // Fixed a bug where the tiles weren't being shifted to "near" (0,0,0)
239 // Revision 1.11 1998/07/04 00:54:30 curt
240 // Added automatic mipmap generation.
242 // When rendering fragments, use saved model view matrix from associated tile
243 // rather than recalculating it with push() translate() pop().
245 // Revision 1.10 1998/05/23 14:09:22 curt
246 // Added tile.cxx and tile.hxx.
247 // Working on rewriting the tile management system so a tile is just a list
248 // fragments, and the fragment record contains the display list for that fragment.
250 // Revision 1.9 1998/05/20 20:53:54 curt
251 // Moved global ref point and radius (bounding sphere info, and offset) to
252 // data file rather than calculating it on the fly.
253 // Fixed polygon winding problem in scenery generation stage rather than
254 // compensating for it on the fly.
255 // Made a fgTILECACHE class.
257 // Revision 1.8 1998/05/16 13:09:57 curt
258 // Beginning to add support for view frustum culling.
259 // Added some temporary code to calculate bouding radius, until the
260 // scenery generation tools and scenery can be updated.
262 // Revision 1.7 1998/05/13 18:26:41 curt
263 // Root path info moved to fgOPTIONS.
265 // Revision 1.6 1998/05/02 01:52:17 curt
266 // Playing around with texture coordinates.
268 // Revision 1.5 1998/04/30 12:35:31 curt
269 // Added a command line rendering option specify smooth/flat shading.
271 // Revision 1.4 1998/04/28 01:21:43 curt
272 // Tweaked texture parameter calculations to keep the number smaller. This
273 // avoids the "swimming" problem.
274 // Type-ified fgTIME and fgVIEW.
276 // Revision 1.3 1998/04/25 22:06:32 curt
277 // Edited cvs log messages in source files ... bad bad bad!
279 // Revision 1.2 1998/04/24 00:51:08 curt
280 // Wrapped "#include <config.h>" in "#ifdef HAVE_CONFIG_H"
281 // Tweaked the scenery file extentions to be "file.obj" (uncompressed)
282 // or "file.obz" (compressed.)
284 // Revision 1.1 1998/04/22 13:22:46 curt
285 // C++ - ifing the code a bit.
287 // Revision 1.11 1998/04/18 04:14:07 curt
288 // Moved fg_debug.c to it's own library.
290 // Revision 1.10 1998/04/14 02:23:17 curt
291 // Code reorganizations. Added a Lib/ directory for more general libraries.
293 // Revision 1.9 1998/04/08 23:30:07 curt
294 // Adopted Gnu automake/autoconf system.
296 // Revision 1.8 1998/04/03 22:11:38 curt
297 // Converting to Gnu autoconf system.
299 // Revision 1.7 1998/02/01 03:39:55 curt
302 // Revision 1.6 1998/01/31 00:43:26 curt
303 // Added MetroWorks patches from Carmen Volpe.
305 // Revision 1.5 1998/01/29 00:51:39 curt
306 // First pass at tile cache, dynamic tile loading and tile unloading now works.
308 // Revision 1.4 1998/01/27 03:26:43 curt
309 // Playing with new fgPrintf command.
311 // Revision 1.3 1998/01/27 00:48:03 curt
312 // Incorporated Paul Bleisch's <pbleisch@acm.org> new debug message
313 // system and commandline/config file processing code.
315 // Revision 1.2 1998/01/26 15:55:24 curt
316 // Progressing on building dynamic scenery system.
318 // Revision 1.1 1998/01/24 00:03:29 curt