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flightgear/Scenery/tilemgr.cxx
curt eda1cfe31c No .h for STL includes. 
Minor view culling optimizations.
1998-06-03 00:47:50 +00:00

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// tilemgr.cxx -- routines to handle dynamic management of scenery tiles
//
// 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 <Aircraft/aircraft.h>
#include <Scenery/obj.hxx>
#include <Scenery/scenery.hxx>
#include <Scenery/tilecache.hxx>
#include <Bucket/bucketutils.h>
#include <Debug/fg_debug.h>
#include <Include/fg_constants.h>
#include <Include/fg_types.h>
#include <Main/options.hxx>
#include <Main/views.hxx>
#include <Math/mat3.h>
#define FG_LOCAL_X_Y 81 // max(o->tile_diameter) ** 2
// closest (potentially viewable) tiles, centered on current tile.
// This is an array of pointers to cache indexes.
int tiles[FG_LOCAL_X_Y];
// Initialize the Tile Manager subsystem
int fgTileMgrInit( void ) {
fgPrintf( FG_TERRAIN, FG_INFO, "Initializing Tile Manager subsystem.\n");
return 1;
}
// load a tile
void fgTileMgrLoadTile( struct fgBUCKET *p, int *index) {
fgTILECACHE *c;
c = &global_tile_cache;
fgPrintf( FG_TERRAIN, FG_DEBUG, "Updating for bucket %d %d %d %d\n",
p->lon, p->lat, p->x, p->y);
// if not in cache, load tile into the next available slot
if ( (*index = c->Exists(p)) < 0 ) {
*index = c->NextAvail();
c->EntryFillIn(*index, p);
}
fgPrintf( FG_TERRAIN, FG_DEBUG, "Selected cache index of %d\n", *index);
}
// given the current lon/lat, fill in the array of local chunks. If
// the chunk isn't already in the cache, then read it from disk.
int fgTileMgrUpdate( void ) {
fgTILECACHE *c;
fgFLIGHT *f;
fgOPTIONS *o;
struct fgBUCKET p1, p2;
static struct fgBUCKET p_last = {-1000, 0, 0, 0};
int i, j, dw, dh;
c = &global_tile_cache;
f = current_aircraft.flight;
o = &current_options;
fgBucketFind(FG_Longitude * RAD_TO_DEG, FG_Latitude * RAD_TO_DEG, &p1);
dw = o->tile_diameter / 2;
dh = o->tile_diameter / 2;
if ( (p1.lon == p_last.lon) && (p1.lat == p_last.lat) &&
(p1.x == p_last.x) && (p1.y == p_last.y) ) {
// same bucket as last time
fgPrintf( FG_TERRAIN, FG_DEBUG, "Same bucket as last time\n");
} else if ( p_last.lon == -1000 ) {
// First time through, initialize the system and load all
// relavant tiles
fgPrintf( FG_TERRAIN, FG_INFO, " First time through ... ");
fgPrintf( FG_TERRAIN, FG_INFO, " Updating Tile list for %d,%d %d,%d\n",
p1.lon, p1.lat, p1.x, p1.y);
fgPrintf( FG_TERRAIN, FG_INFO, " Loading %d tiles\n",
o->tile_diameter * o->tile_diameter);
// wipe/initialize tile cache
c->Init();
// build the local area list and update cache
for ( j = 0; j < o->tile_diameter; j++ ) {
for ( i = 0; i < o->tile_diameter; i++ ) {
fgBucketOffset(&p1, &p2, i - dw, j - dh);
fgTileMgrLoadTile(&p2, &tiles[(j*o->tile_diameter) + i]);
}
}
} else {
// We've moved to a new bucket, we need to scroll our
// structures, and load in the new tiles
// CURRENTLY THIS ASSUMES WE CAN ONLY MOVE TO ADJACENT TILES.
// AT ULTRA HIGH SPEEDS THIS ASSUMPTION MAY NOT BE VALID IF
// THE AIRCRAFT CAN SKIP A TILE IN A SINGLE ITERATION.
fgPrintf( FG_TERRAIN, FG_INFO, "Updating Tile list for %d,%d %d,%d\n",
p1.lon, p1.lat, p1.x, p1.y);
if ( (p1.lon > p_last.lon) ||
( (p1.lon == p_last.lon) && (p1.x > p_last.x) ) ) {
fgPrintf( FG_TERRAIN, FG_INFO, " Loading %d tiles\n",
o->tile_diameter);
for ( j = 0; j < o->tile_diameter; j++ ) {
// scrolling East
for ( i = 0; i < o->tile_diameter - 1; i++ ) {
tiles[(j*o->tile_diameter) + i] =
tiles[(j*o->tile_diameter) + i + 1];
}
// load in new column
fgBucketOffset(&p_last, &p2, dw + 1, j - dh);
fgTileMgrLoadTile(&p2, &tiles[(j*o->tile_diameter) +
o->tile_diameter - 1]);
}
} else if ( (p1.lon < p_last.lon) ||
( (p1.lon == p_last.lon) && (p1.x < p_last.x) ) ) {
fgPrintf( FG_TERRAIN, FG_INFO, " Loading %d tiles\n",
o->tile_diameter);
for ( j = 0; j < o->tile_diameter; j++ ) {
// scrolling West
for ( i = o->tile_diameter - 1; i > 0; i-- ) {
tiles[(j*o->tile_diameter) + i] =
tiles[(j*o->tile_diameter) + i - 1];
}
// load in new column
fgBucketOffset(&p_last, &p2, -dw - 1, j - dh);
fgTileMgrLoadTile(&p2, &tiles[(j*o->tile_diameter) + 0]);
}
}
if ( (p1.lat > p_last.lat) ||
( (p1.lat == p_last.lat) && (p1.y > p_last.y) ) ) {
fgPrintf( FG_TERRAIN, FG_INFO, " Loading %d tiles\n",
o->tile_diameter);
for ( i = 0; i < o->tile_diameter; i++ ) {
// scrolling North
for ( j = 0; j < o->tile_diameter - 1; j++ ) {
tiles[(j * o->tile_diameter) + i] =
tiles[((j+1) * o->tile_diameter) + i];
}
// load in new column
fgBucketOffset(&p_last, &p2, i - dw, dh + 1);
fgTileMgrLoadTile(&p2, &tiles[((o->tile_diameter-1) *
o->tile_diameter) + i]);
}
} else if ( (p1.lat < p_last.lat) ||
( (p1.lat == p_last.lat) && (p1.y < p_last.y) ) ) {
fgPrintf( FG_TERRAIN, FG_INFO, " Loading %d tiles\n",
o->tile_diameter);
for ( i = 0; i < o->tile_diameter; i++ ) {
// scrolling South
for ( j = o->tile_diameter - 1; j > 0; j-- ) {
tiles[(j * o->tile_diameter) + i] =
tiles[((j-1) * o->tile_diameter) + i];
}
// load in new column
fgBucketOffset(&p_last, &p2, i - dw, -dh - 1);
fgTileMgrLoadTile(&p2, &tiles[0 + i]);
}
}
}
p_last.lon = p1.lon;
p_last.lat = p1.lat;
p_last.x = p1.x;
p_last.y = p1.y;
return 1;
}
// Calculate if point/radius is inside view frustum
static int viewable( fgCartesianPoint3d *cp, double radius ) {
fgVIEW *v;
MAT3hvec world, eye;
int viewable = 1; // start by assuming it's viewable
double x0, x1, y1, slope;
v = &current_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);
// Check near clip plane
if ( eye[2] - radius > 0.0 ) {
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;
x0 = x1 - y1 / slope;
// printf("(r) x1 = %.2f y1 = %.2f\n", x1, y1);
// printf("eye[0] = %.2f eye[2] = %.2f\n", eye[0], eye[2]);
// printf("(r) x0 = %.2f slope_x = %.2f radius = %.2f\n",
// x0, slope, radius);
if ( eye[2] > slope * (eye[0] - x0) ) {
return(0);
}
// check left clip plane (from eye perspective)
x1 = -x1;
slope = -slope;
x0 = x1 - y1 / slope;
// printf("(r) x1 = %.2f y1 = %.2f\n", x1, y1);
// printf("eye[0] = %.2f eye[2] = %.2f\n", eye[0], eye[2]);
// printf("(r) x0 = %.2f slope_x = %.2f radius = %.2f\n",
// x0, slope, radius);
if ( eye[2] > slope * (eye[0] - x0) ) {
return(0);
}
// check bottom clip plane (from eye perspective)
x1 = -(v->cos_fov_y) * radius;
y1 = v->sin_fov_y * radius;
slope = v->slope_y;
x0 = x1 - y1 / slope;
// printf("(r) x1 = %.2f y1 = %.2f\n", x1, y1);
// printf("eye[1] = %.2f eye[2] = %.2f\n", eye[1], eye[2]);
// printf("(r) x0 = %.2f slope_y = %.2f radius = %.2f\n",
// x0, slope, radius);
if ( eye[2] > slope * (eye[1] - x0) ) {
return(0);
}
// check top clip plane (from eye perspective)
x1 = -x1;
slope = -slope;
x0 = x1 - y1 / slope;
// printf("(r) x1 = %.2f y1 = %.2f\n", x1, y1);
// printf("eye[1] = %.2f eye[2] = %.2f\n", eye[1], eye[2]);
// printf("(r) x0 = %.2f slope_y = %.2f radius = %.2f\n",
// x0, slope, radius);
if ( eye[2] > slope * (eye[1] - x0) ) {
return(0);
}
return(viewable);
}
// Render the local tiles
void fgTileMgrRender( void ) {
fgTILECACHE *c;
fgFLIGHT *f;
fgOPTIONS *o;
fgTILE *t;
fgVIEW *v;
struct fgBUCKET p;
fgCartesianPoint3d offset;
fgFRAGMENT fragment;
list < fgFRAGMENT > :: iterator current;
list < fgFRAGMENT > :: iterator last;
int i;
int index;
int culled = 0;
int drawn = 0;
c = &global_tile_cache;
f = current_aircraft.flight;
o = &current_options;
v = &current_view;
// Find current translation offset
fgBucketFind(FG_Longitude * RAD_TO_DEG, FG_Latitude * RAD_TO_DEG, &p);
index = c->Exists(&p);
t = c->GetTile(index);
fgPrintf( FG_TERRAIN, FG_DEBUG,
"Pos = (%.2f, %.2f) Current bucket = %d %d %d %d Index = %ld\n",
FG_Longitude * RAD_TO_DEG, FG_Latitude * RAD_TO_DEG,
p.lon, p.lat, p.x, p.y, fgBucketGenIndex(&p) );
for ( i = 0; i < (o->tile_diameter * o->tile_diameter); i++ ) {
index = tiles[i];
// fgPrintf( FG_TERRAIN, FG_DEBUG, "Index = %d\n", index);
t = c->GetTile(index);
// calculate tile offset
offset.x = t->center.x - scenery.center.x;
offset.y = t->center.y - scenery.center.y;
offset.z = t->center.z - scenery.center.z;
// Course (tile based) culling
if ( viewable(&offset, t->bounding_radius) ) {
// at least a portion of this tile is viewable
xglPushMatrix();
xglTranslatef(offset.x, offset.y, offset.z);
// traverse fragment list for tile
current = t->fragment_list.begin();
last = t->fragment_list.end();
while ( current != last ) {
fragment = *current++;
if ( fragment.display_list >= 0 ) {
// Fine (fragment based) culling
offset.x = fragment.center.x - scenery.center.x;
offset.y = fragment.center.y - scenery.center.y;
offset.z = fragment.center.z - scenery.center.z;
if ( viewable(&offset, fragment.bounding_radius * 2) ) {
xglCallList(fragment.display_list);
drawn++;
} else {
// printf("Culled a fragment %.2f %.2f %.2f %.2f\n",
// fragment.center.x, fragment.center.y,
// fragment.center.z, fragment.bounding_radius);
culled++;
}
}
}
xglPopMatrix();
} else {
culled += t->fragment_list.size();
}
}
if ( (drawn + culled) > 0 ) {
v->vfc_ratio = (double)culled / (double)(drawn + culled);
} else {
v->vfc_ratio = 0.0;
}
// printf("drawn = %d culled = %d saved = %.2f\n", drawn, culled,
// v->vfc_ratio);
}
// $Log$
// Revision 1.15 1998/06/03 00:47:51 curt
// No .h for STL includes.
// Minor view culling optimizations.
//
// Revision 1.14 1998/06/01 17:56:20 curt
// Incremental additions to material.cxx (not fully functional)
// Tweaked vfc_ratio math to avoid divide by zero.
//
// Revision 1.13 1998/05/24 02:49:10 curt
// Implimented fragment level view frustum culling.
//
// Revision 1.12 1998/05/23 14:09:23 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 1.11 1998/05/20 20:53:55 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 1.10 1998/05/17 16:59:34 curt
// Frist pass at view frustum culling now operational.
//
// Revision 1.9 1998/05/16 13:09:58 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 1.8 1998/05/07 23:15:21 curt
// Fixed a glTexImage2D() usage bug where width and height were mis-swapped.
// Added support for --tile-radius=n option.
//
// Revision 1.7 1998/05/06 03:16:42 curt
// Added an option to control square tile radius.
//
// Revision 1.6 1998/05/02 01:52:18 curt
// Playing around with texture coordinates.
//
// Revision 1.5 1998/04/30 12:35:32 curt
// Added a command line rendering option specify smooth/flat shading.
//
// Revision 1.4 1998/04/27 03:30:14 curt
// Minor transformation adjustments to try to keep scenery tiles closer to
// (0, 0, 0) GLfloats run out of precision at the distances we need to model
// the earth, but we can do a bunch of pre-transformations using double math
// and then cast to GLfloat once everything is close in where we have less
// precision problems.
//
// 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 00:51:09 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 13:22:48 curt
// C++ - ifing the code a bit.
//
// Revision 1.25 1998/04/18 04:14:07 curt
// Moved fg_debug.c to it's own library.
//
// Revision 1.24 1998/04/14 02:23:18 curt
// Code reorganizations. Added a Lib/ directory for more general libraries.
//
// Revision 1.23 1998/04/08 23:30:08 curt
// Adopted Gnu automake/autoconf system.
//
// Revision 1.22 1998/04/03 22:11:38 curt
// Converting to Gnu autoconf system.
//
// Revision 1.21 1998/03/23 21:23:05 curt
// Debugging output tweaks.
//
// Revision 1.20 1998/03/14 00:30:51 curt
// Beginning initial terrain texturing experiments.
//
// Revision 1.19 1998/02/20 00:16:25 curt
// Thursday's tweaks.
//
// Revision 1.18 1998/02/19 13:05:54 curt
// Incorporated some HUD tweaks from Michelle America.
// Tweaked the sky's sunset/rise colors.
// Other misc. tweaks.
//
// Revision 1.17 1998/02/16 13:39:46 curt
// Miscellaneous weekend tweaks. Fixed? a cache problem that caused whole
// tiles to occasionally be missing.
//
// Revision 1.16 1998/02/12 21:59:53 curt
// Incorporated code changes contributed by Charlie Hotchkiss
// <chotchkiss@namg.us.anritsu.com>
//
// Revision 1.14 1998/02/09 21:30:19 curt
// Fixed a nagging problem with terrain tiles not "quite" matching up perfectly.
//
// Revision 1.13 1998/02/07 15:29:46 curt
// Incorporated HUD changes and struct/typedef changes from Charlie Hotchkiss
// <chotchkiss@namg.us.anritsu.com>
//
// Revision 1.12 1998/02/01 03:39:55 curt
// Minor tweaks.
//
// Revision 1.11 1998/01/31 00:43:27 curt
// Added MetroWorks patches from Carmen Volpe.
//
// Revision 1.10 1998/01/29 00:51:40 curt
// First pass at tile cache, dynamic tile loading and tile unloading now works.
//
// Revision 1.9 1998/01/27 03:26:44 curt
// Playing with new fgPrintf command.
//
// Revision 1.8 1998/01/27 00:48:04 curt
// Incorporated Paul Bleisch's <pbleisch@acm.org> new debug message
// system and commandline/config file processing code.
//
// Revision 1.7 1998/01/26 15:55:25 curt
// Progressing on building dynamic scenery system.
//
// Revision 1.6 1998/01/24 00:03:30 curt
// Initial revision.
//
// Revision 1.5 1998/01/19 19:27:18 curt
// Merged in make system changes from Bob Kuehne <rpk@sgi.com>
// This should simplify things tremendously.
//
// Revision 1.4 1998/01/19 18:40:38 curt
// Tons of little changes to clean up the code and to remove fatal errors
// when building with the c++ compiler.
//
// Revision 1.3 1998/01/13 00:23:11 curt
// Initial changes to support loading and management of scenery tiles. Note,
// there's still a fair amount of work left to be done.
//
// Revision 1.2 1998/01/08 02:22:27 curt
// Continue working on basic features.
//
// Revision 1.1 1998/01/07 23:50:51 curt
// "area" renamed to "tile"
//
// Revision 1.2 1998/01/07 03:29:29 curt
// Given an arbitrary lat/lon, we can now:
// generate a unique index for the chunk containing the lat/lon
// generate a path name to the chunk file
// build a list of the indexes of all the nearby areas.
//
// Revision 1.1 1998/01/07 02:05:48 curt
// Initial revision.
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