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flightgear/Simulator/Scenery/tilecache.cxx
1999-04-05 21:32:32 +00:00

346 lines
10 KiB
C++

// tilecache.cxx -- routines to handle scenery tile caching
//
// Written by Curtis Olson, started January 1998.
//
// Copyright (C) 1997 Curtis L. Olson - curt@infoplane.com
//
// This program is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public License as
// published by the Free Software Foundation; either version 2 of the
// License, or (at your option) any later version.
//
// This program is distributed in the hope that it will be useful, but
// WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
// General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
//
// $Id$
// (Log is kept at end of this file)
#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#ifdef HAVE_WINDOWS_H
# include <windows.h>
#endif
#include <GL/glut.h>
#include <XGL/xgl.h>
#include <Debug/logstream.hxx>
#include <Airports/genapt.hxx>
// #include <Bucket/bucketutils.hxx>
#include <Main/options.hxx>
#include <Main/views.hxx>
#include <Objects/obj.hxx>
#include "tile.hxx"
#include "tilecache.hxx"
// the tile cache
fgTILECACHE global_tile_cache;
// Constructor
fgTILECACHE::fgTILECACHE( void ) {
}
// Initialize the tile cache subsystem
void
fgTILECACHE::init( void )
{
int i;
FG_LOG( FG_TERRAIN, FG_INFO, "Initializing the tile cache." );
for ( i = 0; i < FG_TILE_CACHE_SIZE; i++ ) {
tile_cache[i].used = 0;
}
}
// Search for the specified "bucket" in the cache
int
fgTILECACHE::exists( const FGBucket& p )
{
int i;
for ( i = 0; i < FG_TILE_CACHE_SIZE; i++ ) {
if ( tile_cache[i].tile_bucket == p ) {
FG_LOG( FG_TERRAIN, FG_DEBUG,
"TILE EXISTS in cache ... index = " << i );
return( i );
}
}
return( -1 );
}
// Fill in a tile cache entry with real data for the specified bucket
void
fgTILECACHE::fill_in( int index, FGBucket& p )
{
// Load the appropriate data file and build tile fragment list
string tile_path = current_options.get_fg_root() +
"/Scenery/" + p.gen_base_path() + "/" + p.gen_index_str();
tile_cache[index].used = true;
tile_cache[index].tile_bucket = p;
fgObjLoad( tile_path, &tile_cache[index] );
// tile_cache[ index ].ObjLoad( tile_path, p );
// cout << " ncount before = " << tile_cache[index].ncount << "\n";
// cout << " fragments before = " << tile_cache[index].fragment_list.size()
// << "\n";
string apt_path = tile_path + ".apt";
fgAptGenerate( apt_path, &tile_cache[index] );
// cout << " ncount after = " << tile_cache[index].ncount << "\n";
// cout << " fragments after = " << tile_cache[index].fragment_list.size()
// << "\n";
}
// Free a tile cache entry
void
fgTILECACHE::entry_free( int index )
{
tile_cache[index].release_fragments();
}
// Return index of next available slot in tile cache
int
fgTILECACHE::next_avail( void )
{
Point3D delta, abs_view_pos;
int i;
float max, med, min, tmp;
float dist, max_dist;
int max_index;
max_dist = 0.0;
max_index = 0;
for ( i = 0; i < FG_TILE_CACHE_SIZE; i++ ) {
if ( ! tile_cache[i].used ) {
return(i);
} else {
// calculate approximate distance from view point
abs_view_pos = current_view.get_abs_view_pos();
FG_LOG( FG_TERRAIN, FG_DEBUG,
"DIST Abs view pos = " << abs_view_pos );
FG_LOG( FG_TERRAIN, FG_DEBUG,
" ref point = " << tile_cache[i].center );
delta.setx( fabs(tile_cache[i].center.x() - abs_view_pos.x() ) );
delta.sety( fabs(tile_cache[i].center.y() - abs_view_pos.y() ) );
delta.setz( fabs(tile_cache[i].center.z() - abs_view_pos.z() ) );
max = delta.x(); med = delta.y(); min = delta.z();
if ( max < med ) {
tmp = max; max = med; med = tmp;
}
if ( max < min ) {
tmp = max; max = min; min = tmp;
}
dist = max + (med + min) / 4;
FG_LOG( FG_TERRAIN, FG_DEBUG, " distance = " << dist );
if ( dist > max_dist ) {
max_dist = dist;
max_index = i;
}
}
}
// If we made it this far, then there were no open cache entries.
// We will instead free the furthest cache entry and return it's
// index.
entry_free( max_index );
return( max_index );
}
// Destructor
fgTILECACHE::~fgTILECACHE( void ) {
}
// $Log$
// Revision 1.1 1999/04/05 21:32:49 curt
// Initial revision
//
// Revision 1.23 1999/03/25 19:03:26 curt
// Converted to use new bucket routines.
//
// Revision 1.22 1999/02/26 22:10:04 curt
// Added initial support for native SGI compilers.
//
// Revision 1.21 1998/12/09 18:50:32 curt
// Converted "class fgVIEW" to "class FGView" and updated to make data
// members private and make required accessor functions.
//
// Revision 1.20 1998/11/09 23:40:49 curt
// Bernie Bright <bbright@c031.aone.net.au> writes:
// I've made some changes to the Scenery handling. Basically just tidy ups.
// The main difference is in tile.[ch]xx where I've changed list<fgFRAGMENT> to
// vector<fgFRAGMENT>. Studying our usage patterns this seems reasonable.
// Lists are good if you need to insert/delete elements randomly but we
// don't do that. All access seems to be sequential. Two additional
// benefits are smaller memory usage - each list element requires pointers
// to the next and previous elements, and faster access - vector iterators
// are smaller and faster than list iterators. This should also help
// Charlie Hotchkiss' problem when compiling with Borland and STLport.
//
// ./Lib/Bucket/bucketutils.hxx
// Convenience functions for fgBUCKET.
//
// ./Simulator/Scenery/tile.cxx
// ./Simulator/Scenery/tile.hxx
// Changed fragment list to a vector.
// Added some convenience member functions.
//
// ./Simulator/Scenery/tilecache.cxx
// ./Simulator/Scenery/tilecache.hxx
// use const fgBUCKET& instead of fgBUCKET* where appropriate.
//
// ./Simulator/Scenery/tilemgr.cxx
// ./Simulator/Scenery/tilemgr.hxx
// uses all the new convenience functions.
//
// Revision 1.19 1998/11/06 21:18:21 curt
// Converted to new logstream debugging facility. This allows release
// builds with no messages at all (and no performance impact) by using
// the -DFG_NDEBUG flag.
//
// Revision 1.18 1998/10/16 18:12:28 curt
// Fixed a bug in the conversion to Point3D.
//
// Revision 1.17 1998/10/16 00:55:48 curt
// Converted to Point3D class.
//
// Revision 1.16 1998/09/14 12:45:23 curt
// minor tweaks.
//
// Revision 1.15 1998/08/27 17:02:10 curt
// Contributions from Bernie Bright <bbright@c031.aone.net.au>
// - use strings for fg_root and airport_id and added methods to return
// them as strings,
// - inlined all access methods,
// - made the parsing functions private methods,
// - deleted some unused functions.
// - propogated some of these changes out a bit further.
//
// Revision 1.14 1998/08/25 16:52:43 curt
// material.cxx material.hxx obj.cxx obj.hxx texload.c texload.h moved to
// ../Objects
//
// Revision 1.13 1998/07/13 21:02:00 curt
// Wrote access functions for current fgOPTIONS.
//
// Revision 1.12 1998/07/12 03:18:29 curt
// Added ground collision detection. This involved:
// - saving the entire vertex list for each tile with the tile records.
// - saving the face list for each fragment with the fragment records.
// - code to intersect the current vertical line with the proper face in
// an efficient manner as possible.
// Fixed a bug where the tiles weren't being shifted to "near" (0,0,0)
//
// Revision 1.11 1998/07/04 00:54:30 curt
// Added automatic mipmap generation.
//
// When rendering fragments, use saved model view matrix from associated tile
// rather than recalculating it with push() translate() pop().
//
// Revision 1.10 1998/05/23 14:09:22 curt
// Added tile.cxx and tile.hxx.
// Working on rewriting the tile management system so a tile is just a list
// fragments, and the fragment record contains the display list for that fragment.
//
// Revision 1.9 1998/05/20 20:53:54 curt
// Moved global ref point and radius (bounding sphere info, and offset) to
// data file rather than calculating it on the fly.
// Fixed polygon winding problem in scenery generation stage rather than
// compensating for it on the fly.
// Made a fgTILECACHE class.
//
// Revision 1.8 1998/05/16 13:09:57 curt
// Beginning to add support for view frustum culling.
// Added some temporary code to calculate bouding radius, until the
// scenery generation tools and scenery can be updated.
//
// Revision 1.7 1998/05/13 18:26:41 curt
// Root path info moved to fgOPTIONS.
//
// Revision 1.6 1998/05/02 01:52:17 curt
// Playing around with texture coordinates.
//
// Revision 1.5 1998/04/30 12:35:31 curt
// Added a command line rendering option specify smooth/flat shading.
//
// Revision 1.4 1998/04/28 01:21:43 curt
// Tweaked texture parameter calculations to keep the number smaller. This
// avoids the "swimming" problem.
// Type-ified fgTIME and fgVIEW.
//
// Revision 1.3 1998/04/25 22:06:32 curt
// Edited cvs log messages in source files ... bad bad bad!
//
// Revision 1.2 1998/04/24 00:51:08 curt
// Wrapped "#include <config.h>" in "#ifdef HAVE_CONFIG_H"
// Tweaked the scenery file extentions to be "file.obj" (uncompressed)
// or "file.obz" (compressed.)
//
// Revision 1.1 1998/04/22 13:22:46 curt
// C++ - ifing the code a bit.
//
// Revision 1.11 1998/04/18 04:14:07 curt
// Moved fg_debug.c to it's own library.
//
// Revision 1.10 1998/04/14 02:23:17 curt
// Code reorganizations. Added a Lib/ directory for more general libraries.
//
// Revision 1.9 1998/04/08 23:30:07 curt
// Adopted Gnu automake/autoconf system.
//
// Revision 1.8 1998/04/03 22:11:38 curt
// Converting to Gnu autoconf system.
//
// Revision 1.7 1998/02/01 03:39:55 curt
// Minor tweaks.
//
// Revision 1.6 1998/01/31 00:43:26 curt
// Added MetroWorks patches from Carmen Volpe.
//
// Revision 1.5 1998/01/29 00:51:39 curt
// First pass at tile cache, dynamic tile loading and tile unloading now works.
//
// Revision 1.4 1998/01/27 03:26:43 curt
// Playing with new fgPrintf command.
//
// Revision 1.3 1998/01/27 00:48:03 curt
// Incorporated Paul Bleisch's <pbleisch@acm.org> new debug message
// system and commandline/config file processing code.
//
// Revision 1.2 1998/01/26 15:55:24 curt
// Progressing on building dynamic scenery system.
//
// Revision 1.1 1998/01/24 00:03:29 curt
// Initial revision.