1115 lines
35 KiB
C++
1115 lines
35 KiB
C++
// tilemgr.cxx -- routines to handle dynamic management of scenery tiles
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//
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// Written by Curtis Olson, started January 1998.
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//
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// Copyright (C) 1997 Curtis L. Olson - curt@infoplane.com
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//
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// This program is free software; you can redistribute it and/or
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// modify it under the terms of the GNU General Public License as
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// published by the Free Software Foundation; either version 2 of the
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// License, or (at your option) any later version.
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//
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// This program is distributed in the hope that it will be useful, but
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// WITHOUT ANY WARRANTY; without even the implied warranty of
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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// General Public License for more details.
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//
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// You should have received a copy of the GNU General Public License
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// along with this program; if not, write to the Free Software
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// Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
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//
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// $Id$
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// (Log is kept at end of this file)
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#ifdef HAVE_CONFIG_H
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# include <config.h>
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#endif
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#ifdef HAVE_WINDOWS_H
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# include <windows.h>
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#endif
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#include <GL/glut.h>
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#include <XGL/xgl.h>
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#include <Aircraft/aircraft.hxx>
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#include <Debug/logstream.hxx>
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#include <Bucket/bucketutils.hxx>
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#include <Include/fg_constants.h>
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#include <Main/options.hxx>
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#include <Main/views.hxx>
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#include <Math/fg_geodesy.hxx>
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#include <Math/mat3.h>
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#include <Math/point3d.hxx>
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#include <Math/polar3d.hxx>
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#include <Math/vector.hxx>
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#include <Objects/material.hxx>
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#include <Objects/obj.hxx>
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#include <Weather/weather.hxx>
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#include "scenery.hxx"
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#include "tile.hxx"
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#include "tilecache.hxx"
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#include "tilemgr.hxx"
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// to test clipping speedup in fgTileMgrRender()
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#if defined ( USE_FAST_FOV_CLIP )
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// #define TEST_FOV_CLIP
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// #define TEST_ELEV
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#endif
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#define FG_LOCAL_X_Y 81 // max(o->tile_diameter) ** 2
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#define FG_SQUARE( X ) ( (X) * (X) )
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#if defined(USE_MEM) || defined(WIN32)
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# define FG_MEM_COPY(to,from,n) memcpy(to, from, n)
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#else
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# define FG_MEM_COPY(to,from,n) bcopy(from, to, n)
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#endif
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// closest (potentially viewable) tiles, centered on current tile.
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// This is an array of pointers to cache indexes.
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int tiles[FG_LOCAL_X_Y];
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// Initialize the Tile Manager subsystem
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int fgTileMgrInit( void ) {
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FG_LOG( FG_TERRAIN, FG_INFO, "Initializing Tile Manager subsystem." );
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// load default material library
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material_mgr.load_lib();
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return 1;
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}
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// load a tile
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void fgTileMgrLoadTile( const fgBUCKET& p, int *index) {
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fgTILECACHE *c;
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c = &global_tile_cache;
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FG_LOG( FG_TERRAIN, FG_DEBUG, "Updating for bucket " << p );
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// if not in cache, load tile into the next available slot
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*index = c->exists(p);
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if ( *index < 0 ) {
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*index = c->next_avail();
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c->fill_in(*index, p);
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}
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FG_LOG( FG_TERRAIN, FG_DEBUG, "Selected cache index: " << *index );
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}
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// Calculate shortest distance from point to line
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static double point_line_dist_squared( const Point3D& tc, const Point3D& vp,
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MAT3vec d )
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{
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MAT3vec p, p0;
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double dist;
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p[0] = tc.x(); p[1] = tc.y(); p[2] = tc.z();
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p0[0] = vp.x(); p0[1] = vp.y(); p0[2] = vp.z();
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dist = fgPointLineSquared(p, p0, d);
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// cout << "dist = " << dist << endl;
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return(dist);
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}
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// Determine scenery altitude. Normally this just happens when we
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// render the scene, but we'd also like to be able to do this
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// explicitely. lat & lon are in radians. abs_view_pos in meters.
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// Returns result in meters.
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double
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fgTileMgrCurElevNEW( const fgBUCKET& p ) {
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fgTILE *t;
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fgFRAGMENT *frag_ptr;
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Point3D abs_view_pos = current_view.get_abs_view_pos();
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Point3D earth_center(0.0);
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Point3D result;
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MAT3vec local_up;
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double dist, lat_geod, alt, sea_level_r;
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int index;
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local_up[0] = abs_view_pos.x();
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local_up[1] = abs_view_pos.y();
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local_up[2] = abs_view_pos.z();
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// Find current translation offset
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// fgBucketFind(lon * RAD_TO_DEG, lat * RAD_TO_DEG, &p);
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index = global_tile_cache.exists(p);
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if ( index < 0 ) {
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FG_LOG( FG_TERRAIN, FG_WARN, "Tile not found" );
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return 0.0;
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}
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t = global_tile_cache.get_tile(index);
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scenery.next_center = t->center;
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FG_LOG( FG_TERRAIN, FG_DEBUG,
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"Current bucket = " << p << " Index = " << fgBucketGenIndex(&p) );
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FG_LOG( FG_TERRAIN, FG_DEBUG,
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"abs_view_pos = " << abs_view_pos );
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// calculate tile offset
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// x = (t->offset.x = t->center.x - scenery.center.x);
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// y = (t->offset.y = t->center.y - scenery.center.y);
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// z = (t->offset.z = t->center.z - scenery.center.z);
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// calc current terrain elevation calculate distance from
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// vertical tangent line at current position to center of
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// tile.
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/* printf("distance squared = %.2f, bounding radius = %.2f\n",
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point_line_dist_squared(&(t->offset), &(v->view_pos),
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v->local_up), t->bounding_radius); */
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dist = point_line_dist_squared( t->center, abs_view_pos, local_up );
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if ( dist < FG_SQUARE(t->bounding_radius) ) {
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// traverse fragment list for tile
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fgTILE::FragmentIterator current = t->begin();
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fgTILE::FragmentIterator last = t->end();
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for ( ; current != last; ++current ) {
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frag_ptr = &(*current);
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/* printf("distance squared = %.2f, bounding radius = %.2f\n",
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point_line_dist_squared( &(frag_ptr->center),
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&abs_view_pos), local_up),
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frag_ptr->bounding_radius); */
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dist = point_line_dist_squared( frag_ptr->center,
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abs_view_pos,
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local_up);
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if ( dist <= FG_SQUARE(frag_ptr->bounding_radius) ) {
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if ( frag_ptr->intersect( abs_view_pos,
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earth_center, 0, result ) ) {
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FG_LOG( FG_TERRAIN, FG_DEBUG, "intersection point " <<
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result );
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// compute geocentric coordinates of tile center
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Point3D pp = fgCartToPolar3d(result);
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FG_LOG( FG_TERRAIN, FG_DEBUG, " polar form = " << pp );
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// convert to geodetic coordinates
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fgGeocToGeod(pp.lat(), pp.radius(), &lat_geod,
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&alt, &sea_level_r);
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// printf("alt = %.2f\n", alt);
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// exit since we found an intersection
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if ( alt > -9999.0 ) {
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// printf("returning alt\n");
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return alt;
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} else {
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// printf("returning 0\n");
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return 0.0;
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}
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}
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}
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}
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}
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FG_LOG( FG_TERRAIN, FG_INFO, "(new) no terrain intersection found" );
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return 0.0;
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}
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// Determine scenery altitude. Normally this just happens when we
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// render the scene, but we'd also like to be able to do this
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// explicitely. lat & lon are in radians. abs_view_pos in meters.
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// Returns result in meters.
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double
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fgTileMgrCurElev( double lon, double lat, const Point3D& abs_view_pos ) {
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fgTILECACHE *c;
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fgTILE *t;
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// fgVIEW *v;
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fgFRAGMENT *frag_ptr;
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fgBUCKET p;
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Point3D earth_center(0.0);
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Point3D result;
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MAT3vec local_up;
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double dist, lat_geod, alt, sea_level_r;
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// double x, y, z;
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int index;
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c = &global_tile_cache;
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// v = ¤t_view;
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local_up[0] = abs_view_pos.x();
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local_up[1] = abs_view_pos.y();
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local_up[2] = abs_view_pos.z();
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FG_LOG( FG_TERRAIN, FG_DEBUG, "Absolute view pos = " << abs_view_pos );
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// Find current translation offset
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fgBucketFind(lon * RAD_TO_DEG, lat * RAD_TO_DEG, &p);
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index = c->exists(p);
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if ( index < 0 ) {
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FG_LOG( FG_TERRAIN, FG_WARN, "Tile not found" );
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return 0.0;
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}
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t = c->get_tile(index);
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scenery.next_center = t->center;
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FG_LOG( FG_TERRAIN, FG_DEBUG,
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"Pos = (" << lon * RAD_TO_DEG << ", " << lat * RAD_TO_DEG
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<< ") Current bucket = " << p
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<< " Index = " << fgBucketGenIndex(&p) );
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// calculate tile offset
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// x = (t->offset.x = t->center.x - scenery.center.x);
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// y = (t->offset.y = t->center.y - scenery.center.y);
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// z = (t->offset.z = t->center.z - scenery.center.z);
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// calc current terrain elevation calculate distance from
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// vertical tangent line at current position to center of
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// tile.
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/* printf("distance squared = %.2f, bounding radius = %.2f\n",
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point_line_dist_squared(&(t->offset), &(v->view_pos),
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v->local_up), t->bounding_radius); */
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dist = point_line_dist_squared( t->center, abs_view_pos, local_up );
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if ( dist < FG_SQUARE(t->bounding_radius) ) {
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// traverse fragment list for tile
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fgTILE::FragmentIterator current = t->begin();
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fgTILE::FragmentIterator last = t->end();
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for ( ; current != last; ++current ) {
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frag_ptr = &(*current);
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/* printf("distance squared = %.2f, bounding radius = %.2f\n",
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point_line_dist_squared( &(frag_ptr->center),
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&abs_view_pos), local_up),
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frag_ptr->bounding_radius); */
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dist = point_line_dist_squared( frag_ptr->center,
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abs_view_pos,
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local_up);
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if ( dist <= FG_SQUARE(frag_ptr->bounding_radius) ) {
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if ( frag_ptr->intersect( abs_view_pos,
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earth_center, 0, result ) ) {
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FG_LOG( FG_TERRAIN, FG_DEBUG, "intersection point " <<
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result );
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// compute geocentric coordinates of tile center
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Point3D pp = fgCartToPolar3d(result);
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FG_LOG( FG_TERRAIN, FG_DEBUG, " polar form = " << pp );
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// convert to geodetic coordinates
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fgGeocToGeod(pp.lat(), pp.radius(), &lat_geod,
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&alt, &sea_level_r);
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// printf("alt = %.2f\n", alt);
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// exit since we found an intersection
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if ( alt > -9999.0 ) {
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// printf("returning alt\n");
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return alt;
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} else {
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// printf("returning 0\n");
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return 0.0;
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}
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}
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}
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}
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}
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FG_LOG( FG_TERRAIN, FG_INFO, "(old) no terrain intersection found" );
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return 0.0;
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}
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// given the current lon/lat, fill in the array of local chunks. If
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// the chunk isn't already in the cache, then read it from disk.
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int fgTileMgrUpdate( void ) {
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fgTILECACHE *c;
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FGInterface *f;
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fgBUCKET p1, p2;
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static fgBUCKET p_last = {-1000, 0, 0, 0};
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int tile_diameter;
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int i, j, dw, dh;
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c = &global_tile_cache;
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f = current_aircraft.fdm_state;
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tile_diameter = current_options.get_tile_diameter();
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fgBucketFind( f->get_Longitude() * RAD_TO_DEG,
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f->get_Latitude() * RAD_TO_DEG, &p1);
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dw = tile_diameter / 2;
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dh = tile_diameter / 2;
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if ( p1 == p_last ) {
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// same bucket as last time
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FG_LOG( FG_TERRAIN, FG_DEBUG, "Same bucket as last time" );
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} else if ( p_last.lon == -1000 ) {
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// First time through, initialize the system and load all
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// relavant tiles
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FG_LOG( FG_TERRAIN, FG_INFO, "Updating Tile list for " << p1 );
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FG_LOG( FG_TERRAIN, FG_INFO, " First time through ... " );
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FG_LOG( FG_TERRAIN, FG_INFO, " Updating Tile list for " << p1 );
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FG_LOG( FG_TERRAIN, FG_INFO, " Loading "
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<< tile_diameter * tile_diameter << " tiles" );
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// wipe/initialize tile cache
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c->init();
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// build the local area list and update cache
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for ( j = 0; j < tile_diameter; j++ ) {
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for ( i = 0; i < tile_diameter; i++ ) {
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fgBucketOffset(&p1, &p2, i - dw, j - dh);
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fgTileMgrLoadTile( p2, &tiles[(j*tile_diameter) + i]);
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}
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}
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} else {
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// We've moved to a new bucket, we need to scroll our
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// structures, and load in the new tiles
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// CURRENTLY THIS ASSUMES WE CAN ONLY MOVE TO ADJACENT TILES.
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// AT ULTRA HIGH SPEEDS THIS ASSUMPTION MAY NOT BE VALID IF
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// THE AIRCRAFT CAN SKIP A TILE IN A SINGLE ITERATION.
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FG_LOG( FG_TERRAIN, FG_INFO, "Updating Tile list for " << p1 );
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if ( (p1.lon > p_last.lon) ||
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( (p1.lon == p_last.lon) && (p1.x > p_last.x) ) ) {
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FG_LOG( FG_TERRAIN, FG_INFO,
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" Loading " << tile_diameter << "tiles" );
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for ( j = 0; j < tile_diameter; j++ ) {
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// scrolling East
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for ( i = 0; i < tile_diameter - 1; i++ ) {
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tiles[(j*tile_diameter) + i] =
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tiles[(j*tile_diameter) + i + 1];
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}
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// load in new column
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fgBucketOffset(&p_last, &p2, dw + 1, j - dh);
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fgTileMgrLoadTile( p2, &tiles[(j*tile_diameter) +
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tile_diameter - 1]);
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}
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} else if ( (p1.lon < p_last.lon) ||
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( (p1.lon == p_last.lon) && (p1.x < p_last.x) ) ) {
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FG_LOG( FG_TERRAIN, FG_INFO,
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" Loading " << tile_diameter << "tiles" );
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for ( j = 0; j < tile_diameter; j++ ) {
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// scrolling West
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for ( i = tile_diameter - 1; i > 0; i-- ) {
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tiles[(j*tile_diameter) + i] =
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tiles[(j*tile_diameter) + i - 1];
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}
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// load in new column
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fgBucketOffset(&p_last, &p2, -dw - 1, j - dh);
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fgTileMgrLoadTile( p2, &tiles[(j*tile_diameter) + 0]);
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}
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}
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if ( (p1.lat > p_last.lat) ||
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( (p1.lat == p_last.lat) && (p1.y > p_last.y) ) ) {
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FG_LOG( FG_TERRAIN, FG_INFO,
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" Loading " << tile_diameter << "tiles" );
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for ( i = 0; i < tile_diameter; i++ ) {
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// scrolling North
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for ( j = 0; j < tile_diameter - 1; j++ ) {
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tiles[(j * tile_diameter) + i] =
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tiles[((j+1) * tile_diameter) + i];
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}
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// load in new column
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fgBucketOffset(&p_last, &p2, i - dw, dh + 1);
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fgTileMgrLoadTile( p2, &tiles[((tile_diameter-1) *
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tile_diameter) + i]);
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}
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} else if ( (p1.lat < p_last.lat) ||
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( (p1.lat == p_last.lat) && (p1.y < p_last.y) ) ) {
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FG_LOG( FG_TERRAIN, FG_INFO,
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" Loading " << tile_diameter << "tiles" );
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for ( i = 0; i < tile_diameter; i++ ) {
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// scrolling South
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for ( j = tile_diameter - 1; j > 0; j-- ) {
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tiles[(j * tile_diameter) + i] =
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tiles[((j-1) * tile_diameter) + i];
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}
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// load in new column
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fgBucketOffset(&p_last, &p2, i - dw, -dh - 1);
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fgTileMgrLoadTile( p2, &tiles[0 + i]);
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}
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}
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}
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// find our current elevation (feed in the current bucket to save work)
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Point3D geod_pos = Point3D( f->get_Longitude(), f->get_Latitude(), 0.0);
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Point3D tmp_abs_view_pos = fgGeodToCart(geod_pos);
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scenery.cur_elev =
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fgTileMgrCurElev( f->get_Longitude(), f->get_Latitude(),
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tmp_abs_view_pos );
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p_last.lon = p1.lon;
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p_last.lat = p1.lat;
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p_last.x = p1.x;
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p_last.y = p1.y;
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return 1;
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}
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// Calculate if point/radius is inside view frustum
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static int viewable( const Point3D& cp, double radius ) {
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int viewable = 1; // start by assuming it's viewable
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double x1, y1;
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/********************************/
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#if defined( USE_FAST_FOV_CLIP ) // views.hxx
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/********************************/
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|
MAT3vec eye;
|
|
double *mat;
|
|
double x, y, z;
|
|
|
|
x = cp.x();
|
|
y = cp.y();
|
|
z = cp.z();
|
|
|
|
mat = (double *)(current_view.get_WORLD_TO_EYE());
|
|
|
|
eye[2] = x*mat[2] + y*mat[6] + z*mat[10] + mat[14];
|
|
|
|
// Check near and far clip plane
|
|
if( ( eye[2] > radius ) ||
|
|
( eye[2] + radius + current_weather.get_visibility() < 0) )
|
|
{
|
|
return(0);
|
|
}
|
|
|
|
eye[0] = (x*mat[0] + y*mat[4] + z*mat[8] + mat[12])
|
|
* current_view.get_slope_x();
|
|
|
|
// check right and left clip plane (from eye perspective)
|
|
x1 = radius * current_view.get_fov_x_clip();
|
|
if( (eye[2] > -(eye[0]+x1)) || (eye[2] > (eye[0]-x1)) )
|
|
{
|
|
return(0);
|
|
}
|
|
|
|
eye[1] = (x*mat[1] + y*mat[5] + z*mat[9] + mat[13])
|
|
* current_view.get_slope_y();
|
|
|
|
// check bottom and top clip plane (from eye perspective)
|
|
y1 = radius * current_view.get_fov_y_clip();
|
|
if( (eye[2] > -(eye[1]+y1)) || (eye[2] > (eye[1]-y1)) )
|
|
{
|
|
return(0);
|
|
}
|
|
|
|
/********************************/
|
|
#else // DO NOT USE_FAST_FOV_CLIP
|
|
/********************************/
|
|
|
|
fgVIEW *v;
|
|
MAT3hvec world, eye;
|
|
double x0, slope;
|
|
|
|
v = ¤t_view;
|
|
|
|
MAT3_SET_HVEC(world, cp->x, cp->y, cp->z, 1.0);
|
|
// MAT3mult_vec(eye, world, v->WORLD_TO_EYE);
|
|
// printf( "\nworld -> eye = %.2f %.2f %.2f radius = %.2f\n",
|
|
// eye[0], eye[1], eye[2], radius);
|
|
|
|
// Use lazy evaluation for calculating eye hvec.
|
|
#define vec world
|
|
#define mat v->WORLD_TO_EYE
|
|
eye[2] = vec[0]*mat[0][2]+vec[1]*mat[1][2]+vec[2]*mat[2][2]+mat[3][2];
|
|
|
|
// Check near clip plane
|
|
if ( eye[2] > radius ) {
|
|
return(0);
|
|
}
|
|
|
|
// Check far clip plane
|
|
if ( eye[2] + radius < -current_weather.get_visibility() ) {
|
|
return(0);
|
|
}
|
|
|
|
// check right clip plane (from eye perspective)
|
|
// y = m * (x - x0) = equation of a line intercepting X axis at x0
|
|
x1 = v->cos_fov_x * radius;
|
|
y1 = v->sin_fov_x * radius;
|
|
slope = v->slope_x;
|
|
eye[0] = vec[0]*mat[0][0]+vec[1]*mat[1][0]+vec[2]*mat[2][0]+mat[3][0];
|
|
|
|
if ( eye[2] > ((slope * (eye[0] - x1)) + y1) ) {
|
|
return( false );
|
|
}
|
|
|
|
// check left clip plane (from eye perspective)
|
|
if ( eye[2] > -((slope * (eye[0] + x1)) - y1) ) {
|
|
return( false );
|
|
}
|
|
|
|
// check bottom clip plane (from eye perspective)
|
|
x1 = -(v->cos_fov_y) * radius;
|
|
y1 = v->sin_fov_y * radius;
|
|
slope = v->slope_y;
|
|
eye[1] = vec[0]*mat[0][1]+vec[1]*mat[1][1]+vec[2]*mat[2][1]+mat[3][1];
|
|
#undef vec
|
|
#undef mat
|
|
|
|
if ( eye[2] > ((slope * (eye[1] - x1)) + y1) ) {
|
|
return( false );
|
|
}
|
|
|
|
// check top clip plane (from eye perspective)
|
|
if ( eye[2] > -((slope * (eye[1] + x1)) - y1) ) {
|
|
return( false );
|
|
}
|
|
|
|
#endif // defined( USE_FAST_FOV_CLIP )
|
|
|
|
return(viewable);
|
|
}
|
|
|
|
|
|
// NEW
|
|
|
|
// inrange() IS THIS POINT WITHIN POSSIBLE VIEWING RANGE ?
|
|
// calculate distance from vertical tangent line at
|
|
// current position to center of object.
|
|
// this is equivalent to
|
|
// dist = point_line_dist_squared( &(t->center), &(v->abs_view_pos),
|
|
// v->local_up );
|
|
// if ( dist < FG_SQUARE(t->bounding_radius) ) {
|
|
//
|
|
// the compiler should inline this for us
|
|
|
|
static int
|
|
inrange( const double radius, const Point3D& center, const Point3D& vp,
|
|
const MAT3vec up)
|
|
{
|
|
MAT3vec u, u1, v;
|
|
// double tmp;
|
|
|
|
// u = p - p0
|
|
u[0] = center.x() - vp.x();
|
|
u[1] = center.y() - vp.y();
|
|
u[2] = center.z() - vp.z();
|
|
|
|
// calculate the projection, u1, of u along d.
|
|
// u1 = ( dot_prod(u, d) / dot_prod(d, d) ) * d;
|
|
|
|
MAT3_SCALE_VEC(u1, up,
|
|
(MAT3_DOT_PRODUCT(u, up) / MAT3_DOT_PRODUCT(up, up)) );
|
|
|
|
// v = u - u1 = vector from closest point on line, p1, to the
|
|
// original point, p.
|
|
MAT3_SUB_VEC(v, u, u1);
|
|
|
|
return( FG_SQUARE(radius) >= MAT3_DOT_PRODUCT(v, v));
|
|
}
|
|
|
|
|
|
// NEW for legibility
|
|
|
|
// update this tile's geometry for current view
|
|
// The Compiler should inline this
|
|
static void
|
|
update_tile_geometry( fgTILE *t, GLdouble *MODEL_VIEW)
|
|
{
|
|
GLdouble *m;
|
|
double x, y, z;
|
|
|
|
// calculate tile offset
|
|
t->offset = t->center - scenery.center;
|
|
|
|
x = t->offset.x();
|
|
y = t->offset.y();
|
|
z = t->offset.z();
|
|
|
|
m = t->model_view;
|
|
|
|
// Calculate the model_view transformation matrix for this tile
|
|
FG_MEM_COPY( m, MODEL_VIEW, 16*sizeof(GLdouble) );
|
|
|
|
// This is equivalent to doing a glTranslatef(x, y, z);
|
|
m[12] += (m[0]*x + m[4]*y + m[8] *z);
|
|
m[13] += (m[1]*x + m[5]*y + m[9] *z);
|
|
m[14] += (m[2]*x + m[6]*y + m[10]*z);
|
|
// m[15] += (m[3]*x + m[7]*y + m[11]*z);
|
|
// m[3] m7[] m[11] are 0.0 see LookAt() in views.cxx
|
|
// so m[15] is unchanged
|
|
}
|
|
|
|
|
|
// Render the local tiles
|
|
void fgTileMgrRender( void ) {
|
|
FGInterface *f;
|
|
fgTILECACHE *c;
|
|
fgTILE *t;
|
|
FGView *v;
|
|
Point3D frag_offset;
|
|
fgFRAGMENT *frag_ptr;
|
|
fgMATERIAL *mtl_ptr;
|
|
int i;
|
|
int tile_diameter;
|
|
int index;
|
|
int culled = 0;
|
|
int drawn = 0;
|
|
|
|
c = &global_tile_cache;
|
|
f = current_aircraft.fdm_state;
|
|
v = ¤t_view;
|
|
|
|
tile_diameter = current_options.get_tile_diameter();
|
|
|
|
// moved to fgTileMgrUpdate, right after we check if we need to
|
|
// load additional tiles:
|
|
// scenery.cur_elev = fgTileMgrCurElev( FG_Longitude, FG_Latitude,
|
|
// v->abs_view_pos );
|
|
|
|
// initialize the transient per-material fragment lists
|
|
material_mgr.init_transient_material_lists();
|
|
|
|
// Pass 1
|
|
// traverse the potentially viewable tile list
|
|
for ( i = 0; i < (tile_diameter * tile_diameter); i++ ) {
|
|
index = tiles[i];
|
|
// fgPrintf( FG_TERRAIN, FG_DEBUG, "Index = %d\n", index);
|
|
t = c->get_tile(index);
|
|
|
|
// calculate tile offset
|
|
t->SetOffset( scenery.center );
|
|
|
|
// Course (tile based) culling
|
|
if ( viewable(t->offset, t->bounding_radius) ) {
|
|
// at least a portion of this tile could be viewable
|
|
|
|
// Calculate the model_view transformation matrix for this tile
|
|
// This is equivalent to doing a glTranslatef(x, y, z);
|
|
t->UpdateViewMatrix( v->get_MODEL_VIEW() );
|
|
|
|
// xglPushMatrix();
|
|
// xglTranslatef(t->offset.x, t->offset.y, t->offset.z);
|
|
|
|
// traverse fragment list for tile
|
|
fgTILE::FragmentIterator current = t->begin();
|
|
fgTILE::FragmentIterator last = t->end();
|
|
|
|
for ( ; current != last; ++current ) {
|
|
frag_ptr = &(*current);
|
|
|
|
if ( frag_ptr->display_list >= 0 ) {
|
|
// Fine (fragment based) culling
|
|
frag_offset = frag_ptr->center - scenery.center;
|
|
|
|
if ( viewable(frag_offset, frag_ptr->bounding_radius*2) ) {
|
|
// add to transient per-material property fragment list
|
|
// frag_ptr->tile_offset.x = t->offset.x;
|
|
// frag_ptr->tile_offset.y = t->offset.y;
|
|
// frag_ptr->tile_offset.z = t->offset.z;
|
|
|
|
mtl_ptr = frag_ptr->material_ptr;
|
|
// printf(" lookup = %s\n", mtl_ptr->texture_name);
|
|
if ( ! mtl_ptr->append_sort_list( frag_ptr ) ) {
|
|
FG_LOG( FG_TERRAIN, FG_ALERT,
|
|
"Overran material sorting array" );
|
|
}
|
|
|
|
// xglCallList(frag_ptr->display_list);
|
|
drawn++;
|
|
} else {
|
|
// printf("Culled a fragment %.2f %.2f %.2f %.2f\n",
|
|
// frag_ptr->center.x, frag_ptr->center.y,
|
|
// frag_ptr->center.z, frag_ptr->bounding_radius);
|
|
culled++;
|
|
}
|
|
}
|
|
}
|
|
|
|
// xglPopMatrix();
|
|
} else {
|
|
culled += t->fragment_list.size();
|
|
}
|
|
}
|
|
|
|
if ( (drawn + culled) > 0 ) {
|
|
v->set_vfc_ratio( (double)culled / (double)(drawn + culled) );
|
|
} else {
|
|
v->set_vfc_ratio( 0.0 );
|
|
}
|
|
// printf("drawn = %d culled = %d saved = %.2f\n", drawn, culled,
|
|
// v->vfc_ratio);
|
|
|
|
// Pass 2
|
|
// traverse the transient per-material fragment lists and render
|
|
// out all fragments for each material property.
|
|
xglPushMatrix();
|
|
material_mgr.render_fragments();
|
|
xglPopMatrix();
|
|
}
|
|
|
|
|
|
// $Log$
|
|
// Revision 1.54 1999/02/26 22:10:05 curt
|
|
// Added initial support for native SGI compilers.
|
|
//
|
|
// Revision 1.53 1999/02/05 21:29:16 curt
|
|
// Modifications to incorporate Jon S. Berndts flight model code.
|
|
//
|
|
// Revision 1.52 1999/01/27 04:49:48 curt
|
|
// Fixes so that the sim can start out at an airport below sea level.
|
|
//
|
|
// Revision 1.51 1998/12/09 18:50:33 curt
|
|
// Converted "class fgVIEW" to "class FGView" and updated to make data
|
|
// members private and make required accessor functions.
|
|
//
|
|
// Revision 1.50 1998/12/06 13:51:25 curt
|
|
// Turned "struct fgWEATHER" into "class FGWeather".
|
|
//
|
|
// Revision 1.49 1998/12/05 15:54:26 curt
|
|
// Renamed class fgFLIGHT to class FGState as per request by JSB.
|
|
//
|
|
// Revision 1.48 1998/12/05 14:20:21 curt
|
|
// Looking into a terrain intersection problem.
|
|
//
|
|
// Revision 1.47 1998/12/05 14:11:19 curt
|
|
// Sun portability tweak.
|
|
//
|
|
// Revision 1.46 1998/12/03 14:15:24 curt
|
|
// Actually set the current scenery elevation based on scenery intersection point
|
|
// rather than calculating the intesection point and throwing it away.
|
|
//
|
|
// Revision 1.45 1998/12/03 01:18:18 curt
|
|
// Converted fgFLIGHT to a class.
|
|
// Tweaks for Sun Portability.
|
|
// Tweaked current terrain elevation code as per NHV.
|
|
//
|
|
// Revision 1.44 1998/11/23 21:49:48 curt
|
|
// minor tweaks.
|
|
//
|
|
// Revision 1.43 1998/11/09 23:40:52 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 1.42 1998/11/06 21:18:23 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 1.41 1998/10/18 01:17:23 curt
|
|
// Point3D tweaks.
|
|
//
|
|
// Revision 1.40 1998/10/17 01:34:28 curt
|
|
// C++ ifying ...
|
|
//
|
|
// Revision 1.39 1998/10/16 00:55:50 curt
|
|
// Converted to Point3D class.
|
|
//
|
|
// Revision 1.38 1998/09/17 18:36:18 curt
|
|
// Tweaks and optimizations by Norman Vine.
|
|
//
|
|
// Revision 1.37 1998/09/15 01:36:45 curt
|
|
// cleaned up my fragment.num_faces hack :-) to use the STL (no need in
|
|
// duplicating work.)
|
|
// Tweaked fgTileMgrRender() do not calc tile matrix unless necessary.
|
|
// removed some unneeded stuff from fgTileMgrCurElev()
|
|
//
|
|
// Revision 1.36 1998/09/14 12:45:26 curt
|
|
// minor tweaks.
|
|
//
|
|
// Revision 1.35 1998/09/10 19:07:16 curt
|
|
// /Simulator/Objects/fragment.hxx
|
|
// Nested fgFACE inside fgFRAGMENT since its not used anywhere else.
|
|
//
|
|
// ./Simulator/Objects/material.cxx
|
|
// ./Simulator/Objects/material.hxx
|
|
// Made fgMATERIAL and fgMATERIAL_MGR bona fide classes with private
|
|
// data members - that should keep the rabble happy :)
|
|
//
|
|
// ./Simulator/Scenery/tilemgr.cxx
|
|
// In viewable() delay evaluation of eye[0] and eye[1] in until they're
|
|
// actually needed.
|
|
// Change to fgTileMgrRender() to call fgMATERIAL_MGR::render_fragments()
|
|
// method.
|
|
//
|
|
// ./Include/fg_stl_config.h
|
|
// ./Include/auto_ptr.hxx
|
|
// Added support for g++ 2.7.
|
|
// Further changes to other files are forthcoming.
|
|
//
|
|
// Brief summary of changes required for g++ 2.7.
|
|
// operator->() not supported by iterators: use (*i).x instead of i->x
|
|
// default template arguments not supported,
|
|
// <functional> doesn't have mem_fun_ref() needed by callbacks.
|
|
// some std include files have different names.
|
|
// template member functions not supported.
|
|
//
|
|
// Revision 1.34 1998/09/09 20:58:09 curt
|
|
// Tweaks to loop constructs with STL usage.
|
|
//
|
|
// Revision 1.33 1998/09/08 15:05:10 curt
|
|
// Optimization by Norman Vine.
|
|
//
|
|
// Revision 1.32 1998/08/25 16:52:44 curt
|
|
// material.cxx material.hxx obj.cxx obj.hxx texload.c texload.h moved to
|
|
// ../Objects
|
|
//
|
|
// Revision 1.31 1998/08/24 20:11:40 curt
|
|
// Tweaks ...
|
|
//
|
|
// Revision 1.30 1998/08/22 14:49:59 curt
|
|
// Attempting to iron out seg faults and crashes.
|
|
// Did some shuffling to fix a initialization order problem between view
|
|
// position, scenery elevation.
|
|
//
|
|
// Revision 1.29 1998/08/20 15:12:06 curt
|
|
// Used a forward declaration of classes fgTILE and fgMATERIAL to eliminate
|
|
// the need for "void" pointers and casts.
|
|
// Quick hack to count the number of scenery polygons that are being drawn.
|
|
//
|
|
// Revision 1.28 1998/08/12 21:13:06 curt
|
|
// material.cxx: don't load textures if they are disabled
|
|
// obj.cxx: optimizations from Norman Vine
|
|
// tile.cxx: minor tweaks
|
|
// tile.hxx: addition of num_faces
|
|
// tilemgr.cxx: minor tweaks
|
|
//
|
|
// Revision 1.27 1998/07/24 21:42:09 curt
|
|
// material.cxx: whups, double method declaration with no definition.
|
|
// obj.cxx: tweaks to avoid errors in SGI's CC.
|
|
// tile.cxx: optimizations by Norman Vine.
|
|
// tilemgr.cxx: optimizations by Norman Vine.
|
|
//
|
|
// Revision 1.26 1998/07/20 12:51:26 curt
|
|
// Added far clip plane to fragment clipping calculations and tie this to
|
|
// weather->visibility. This way you can increase framerates by increasing
|
|
// for and lowering visibility.
|
|
//
|
|
// Revision 1.25 1998/07/13 21:02:01 curt
|
|
// Wrote access functions for current fgOPTIONS.
|
|
//
|
|
// Revision 1.24 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 1.23 1998/07/08 14:47:23 curt
|
|
// Fix GL_MODULATE vs. GL_DECAL problem introduced by splash screen.
|
|
// polare3d.h renamed to polar3d.hxx
|
|
// fg{Cartesian,Polar}Point3d consolodated.
|
|
// Added some initial support for calculating local current ground elevation.
|
|
//
|
|
// Revision 1.22 1998/07/04 00:54:31 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 1.21 1998/06/27 16:54:59 curt
|
|
// Check for GL_VERSION_1_1 or GL_EXT_texture_object to decide whether to use
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// "EXT" versions of texture management routines.
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//
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// Revision 1.20 1998/06/17 21:36:42 curt
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// Load and manage multiple textures defined in the Materials library.
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// Boost max material fagments for each material property to 800.
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// Multiple texture support when rendering.
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//
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// Revision 1.19 1998/06/08 17:57:54 curt
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// Working first pass at material proporty sorting.
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//
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// Revision 1.18 1998/06/06 01:09:32 curt
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// I goofed on the log message in the last commit ... now fixed.
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//
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// Revision 1.17 1998/06/06 01:07:18 curt
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// Increased per material fragment list size from 100 to 400.
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// Now correctly draw viewable fragments in per material order.
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//
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// Revision 1.16 1998/06/05 22:39:55 curt
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// Working on sorting by, and rendering by material properties.
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//
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// Revision 1.15 1998/06/03 00:47:51 curt
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// No .h for STL includes.
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// Minor view culling optimizations.
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//
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// Revision 1.14 1998/06/01 17:56:20 curt
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// Incremental additions to material.cxx (not fully functional)
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// Tweaked vfc_ratio math to avoid divide by zero.
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//
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// Revision 1.13 1998/05/24 02:49:10 curt
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// Implimented fragment level view frustum culling.
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//
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// Revision 1.12 1998/05/23 14:09:23 curt
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// Added tile.cxx and tile.hxx.
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// Working on rewriting the tile management system so a tile is just a list
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// fragments, and the fragment record contains the display list for that fragment.
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//
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// Revision 1.11 1998/05/20 20:53:55 curt
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// Moved global ref point and radius (bounding sphere info, and offset) to
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// data file rather than calculating it on the fly.
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// Fixed polygon winding problem in scenery generation stage rather than
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// compensating for it on the fly.
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// Made a fgTILECACHE class.
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//
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// Revision 1.10 1998/05/17 16:59:34 curt
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// Frist pass at view frustum culling now operational.
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//
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// Revision 1.9 1998/05/16 13:09:58 curt
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// Beginning to add support for view frustum culling.
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// Added some temporary code to calculate bouding radius, until the
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// scenery generation tools and scenery can be updated.
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//
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// Revision 1.8 1998/05/07 23:15:21 curt
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// Fixed a glTexImage2D() usage bug where width and height were mis-swapped.
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// Added support for --tile-radius=n option.
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//
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// Revision 1.7 1998/05/06 03:16:42 curt
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// Added an option to control square tile radius.
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//
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// Revision 1.6 1998/05/02 01:52:18 curt
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// Playing around with texture coordinates.
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//
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// Revision 1.5 1998/04/30 12:35:32 curt
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// Added a command line rendering option specify smooth/flat shading.
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//
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// Revision 1.4 1998/04/27 03:30:14 curt
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// Minor transformation adjustments to try to keep scenery tiles closer to
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// (0, 0, 0) GLfloats run out of precision at the distances we need to model
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// the earth, but we can do a bunch of pre-transformations using double math
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// and then cast to GLfloat once everything is close in where we have less
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// precision problems.
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//
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// Revision 1.3 1998/04/25 22:06:32 curt
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// Edited cvs log messages in source files ... bad bad bad!
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//
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// Revision 1.2 1998/04/24 00:51:09 curt
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// Wrapped "#include <config.h>" in "#ifdef HAVE_CONFIG_H"
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// Tweaked the scenery file extentions to be "file.obj" (uncompressed)
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// or "file.obz" (compressed.)
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//
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// Revision 1.1 1998/04/22 13:22:48 curt
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// C++ - ifing the code a bit.
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//
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// Revision 1.25 1998/04/18 04:14:07 curt
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// Moved fg_debug.c to it's own library.
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//
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// Revision 1.24 1998/04/14 02:23:18 curt
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// Code reorganizations. Added a Lib/ directory for more general libraries.
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//
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// Revision 1.23 1998/04/08 23:30:08 curt
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// Adopted Gnu automake/autoconf system.
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//
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// Revision 1.22 1998/04/03 22:11:38 curt
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// Converting to Gnu autoconf system.
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//
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// Revision 1.21 1998/03/23 21:23:05 curt
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// Debugging output tweaks.
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//
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// Revision 1.20 1998/03/14 00:30:51 curt
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// Beginning initial terrain texturing experiments.
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//
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// Revision 1.19 1998/02/20 00:16:25 curt
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// Thursday's tweaks.
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//
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// Revision 1.18 1998/02/19 13:05:54 curt
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// Incorporated some HUD tweaks from Michelle America.
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// Tweaked the sky's sunset/rise colors.
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// Other misc. tweaks.
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//
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// Revision 1.17 1998/02/16 13:39:46 curt
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// Miscellaneous weekend tweaks. Fixed? a cache problem that caused whole
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// tiles to occasionally be missing.
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//
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// Revision 1.16 1998/02/12 21:59:53 curt
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// Incorporated code changes contributed by Charlie Hotchkiss
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// <chotchkiss@namg.us.anritsu.com>
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//
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// Revision 1.14 1998/02/09 21:30:19 curt
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// Fixed a nagging problem with terrain tiles not "quite" matching up perfectly.
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//
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// Revision 1.13 1998/02/07 15:29:46 curt
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// Incorporated HUD changes and struct/typedef changes from Charlie Hotchkiss
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// <chotchkiss@namg.us.anritsu.com>
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//
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// Revision 1.12 1998/02/01 03:39:55 curt
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// Minor tweaks.
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//
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// Revision 1.11 1998/01/31 00:43:27 curt
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// Added MetroWorks patches from Carmen Volpe.
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//
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// Revision 1.10 1998/01/29 00:51:40 curt
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// First pass at tile cache, dynamic tile loading and tile unloading now works.
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//
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// Revision 1.9 1998/01/27 03:26:44 curt
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// Playing with new fgPrintf command.
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//
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// Revision 1.8 1998/01/27 00:48:04 curt
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// Incorporated Paul Bleisch's <pbleisch@acm.org> new debug message
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// system and commandline/config file processing code.
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//
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// Revision 1.7 1998/01/26 15:55:25 curt
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// Progressing on building dynamic scenery system.
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//
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// Revision 1.6 1998/01/24 00:03:30 curt
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// Initial revision.
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//
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// Revision 1.5 1998/01/19 19:27:18 curt
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// Merged in make system changes from Bob Kuehne <rpk@sgi.com>
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// This should simplify things tremendously.
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//
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// Revision 1.4 1998/01/19 18:40:38 curt
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// Tons of little changes to clean up the code and to remove fatal errors
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// when building with the c++ compiler.
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//
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// Revision 1.3 1998/01/13 00:23:11 curt
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// Initial changes to support loading and management of scenery tiles. Note,
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// there's still a fair amount of work left to be done.
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//
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// Revision 1.2 1998/01/08 02:22:27 curt
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// Continue working on basic features.
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//
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// Revision 1.1 1998/01/07 23:50:51 curt
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// "area" renamed to "tile"
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//
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// Revision 1.2 1998/01/07 03:29:29 curt
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// Given an arbitrary lat/lon, we can now:
|
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// generate a unique index for the chunk containing the lat/lon
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// generate a path name to the chunk file
|
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// build a list of the indexes of all the nearby areas.
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//
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// Revision 1.1 1998/01/07 02:05:48 curt
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// Initial revision.
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