1 /**************************************************************************
2 * GLmain.c -- top level sim routines
4 * Written by Curtis Olson for OpenGL, started May 1997.
6 * Copyright (C) 1997 Curtis L. Olson - curt@infoplane.com
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License as
10 * published by the Free Software Foundation; either version 2 of the
11 * License, or (at your option) any later version.
13 * This program is distributed in the hope that it will be useful, but
14 * WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * General Public License for more details.
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
23 * (Log is kept at end of this file)
24 **************************************************************************/
38 #include "../constants.h"
40 #include "../Aircraft/aircraft.h"
41 #include "../Scenery/mesh.h"
42 #include "../Scenery/scenery.h"
43 #include "../Math/fg_random.h"
44 #include "../Math/mat3.h"
45 #include "../Math/polar.h"
46 #include "../Time/fg_timer.h"
47 #include "../Weather/weather.h"
50 /* This is a record containing all the info for the aircraft currently
52 struct aircraft_params current_aircraft;
55 static GLfloat win_ratio = 1.0;
58 static GLfloat sun_vec[4] = {0.2948, 0.7816, -0.5498, 0.0 };
61 /* extern struct mesh *mesh_ptr; */
62 /* Function prototypes */
63 /* GLint fgSceneryCompile_OLD(); */
64 /* static void fgSceneryDraw_OLD(); */
66 /* pointer to scenery structure */
67 /* static GLint scenery, runway; */
70 double fogDensity = 60000.0; /* in meters */
71 double view_offset = 0.0;
72 double goal_view_offset = 0.0;
75 #define DEFAULT_TIMER_HZ 20
76 #define DEFAULT_MULTILOOP 6
77 #define DEFAULT_MODEL_HZ (DEFAULT_TIMER_HZ * DEFAULT_MULTILOOP)
85 /**************************************************************************
86 * fgInitVisuals() -- Initialize various GL/view parameters
87 **************************************************************************/
89 static void fgInitVisuals() {
90 /* if the 4th field is 0.0, this specifies a direction ... */
91 static GLfloat fogColor[4] = {0.65, 0.65, 0.85, 1.0};
93 glEnable( GL_DEPTH_TEST );
94 /* glFrontFace(GL_CW); */
95 glEnable( GL_CULL_FACE );
97 /* If enabled, normal vectors specified with glNormal are scaled
98 to unit length after transformation. See glNormal. */
99 glEnable( GL_NORMALIZE );
101 glLightfv( GL_LIGHT0, GL_POSITION, sun_vec );
102 glEnable( GL_LIGHTING );
103 glEnable( GL_LIGHT0 );
105 glShadeModel( GL_FLAT ); /* glShadeModel( GL_SMOOTH ); */
108 glFogi (GL_FOG_MODE, GL_LINEAR);
109 /* glFogf (GL_FOG_START, 1.0); */
110 glFogf (GL_FOG_END, fogDensity);
111 glFogfv (GL_FOG_COLOR, fogColor);
112 /* glFogf (GL_FOG_DENSITY, fogDensity); */
113 /* glHint (GL_FOG_HINT, GL_FASTEST); */
115 glClearColor(0.6, 0.6, 0.9, 1.0);
119 /**************************************************************************
120 * Update the view volume, position, and orientation
121 **************************************************************************/
123 static void fgUpdateViewParams() {
124 struct fgCartesianPoint view_pos /*, alt_up */;
125 struct flight_params *f;
126 MAT3mat R, TMP, UP, LOCAL, VIEW;
127 MAT3vec vec, view_up, forward, view_forward, local_up;
129 f = ¤t_aircraft.flight;
131 /* Tell GL we are about to modify the projection parameters */
132 glMatrixMode(GL_PROJECTION);
134 gluPerspective(45.0, 1.0/win_ratio, 1.0, 200000.0);
136 glMatrixMode(GL_MODELVIEW);
139 /* calculate view position in current FG view coordinate system */
140 view_pos = fgPolarToCart(FG_Longitude, FG_Lat_geocentric,
141 FG_Radius_to_vehicle * FEET_TO_METER + 1.0);
142 printf("View pos = %.4f, %.4f, %.4f\n", view_pos.x, view_pos.y, view_pos.z);
144 /* Derive the LOCAL aircraft rotation matrix (roll, pitch, yaw) */
145 MAT3_SET_VEC(vec, 0.0, 0.0, 1.0);
146 MAT3rotate(R, vec, FG_Phi);
147 /* printf("Roll matrix\n"); */
148 /* MAT3print(R, stdout); */
150 MAT3_SET_VEC(vec, 0.0, 1.0, 0.0);
151 /* MAT3mult_vec(vec, vec, R); */
152 MAT3rotate(TMP, vec, FG_Theta);
153 /* printf("Pitch matrix\n"); */
154 /* MAT3print(TMP, stdout); */
157 MAT3_SET_VEC(vec, 1.0, 0.0, 0.0);
158 /* MAT3mult_vec(vec, vec, R); */
159 /* MAT3rotate(TMP, vec, FG_Psi - FG_PI_2); */
160 MAT3rotate(TMP, vec, -FG_Psi);
161 /* printf("Yaw matrix\n");
162 MAT3print(TMP, stdout); */
163 MAT3mult(LOCAL, R, TMP);
164 /* printf("LOCAL matrix\n"); */
165 /* MAT3print(LOCAL, stdout); */
167 /* Derive the local UP transformation matrix based on *geodetic*
169 MAT3_SET_VEC(vec, 0.0, 0.0, 1.0);
170 MAT3rotate(R, vec, FG_Longitude); /* R = rotate about Z axis */
171 /* printf("Longitude matrix\n"); */
172 /* MAT3print(R, stdout); */
174 MAT3_SET_VEC(vec, 0.0, 1.0, 0.0);
175 MAT3mult_vec(vec, vec, R);
176 MAT3rotate(TMP, vec, -FG_Latitude); /* TMP = rotate about X axis */
177 /* printf("Latitude matrix\n"); */
178 /* MAT3print(TMP, stdout); */
180 MAT3mult(UP, R, TMP);
181 /* printf("Local up matrix\n"); */
182 /* MAT3print(UP, stdout); */
184 MAT3_SET_VEC(local_up, 1.0, 0.0, 0.0);
185 MAT3mult_vec(local_up, local_up, UP);
187 printf(" Local Up = (%.4f, %.4f, %.4f)\n", local_up[0], local_up[1],
190 /* Alternative method to Derive local up vector based on
191 * *geodetic* coordinates */
192 /* alt_up = fgPolarToCart(FG_Longitude, FG_Latitude, 1.0); */
193 /* printf(" Alt Up = (%.4f, %.4f, %.4f)\n",
194 alt_up.x, alt_up.y, alt_up.z); */
196 /* Derive the VIEW matrix */
197 MAT3mult(VIEW, LOCAL, UP);
198 /* printf("VIEW matrix\n"); */
199 /* MAT3print(VIEW, stdout); */
201 /* generate the current up, forward, and fwrd-view vectors */
202 MAT3_SET_VEC(vec, 1.0, 0.0, 0.0);
203 MAT3mult_vec(view_up, vec, VIEW);
205 MAT3_SET_VEC(vec, 0.0, 0.0, 1.0);
206 MAT3mult_vec(forward, vec, VIEW);
207 printf("Forward vector is (%.2f,%.2f,%.2f)\n", forward[0], forward[1],
210 MAT3rotate(TMP, view_up, view_offset);
211 MAT3mult_vec(view_forward, forward, TMP);
213 gluLookAt(view_pos.x, view_pos.y, view_pos.z,
214 view_pos.x + view_forward[0], view_pos.y + view_forward[1],
215 view_pos.z + view_forward[2],
216 view_up[0], view_up[1], view_up[2]);
218 glLightfv( GL_LIGHT0, GL_POSITION, sun_vec );
222 /**************************************************************************
223 * Update all Visuals (redraws anything graphics related)
224 **************************************************************************/
226 static void fgUpdateVisuals( void ) {
227 /* update view volume parameters */
228 fgUpdateViewParams();
230 glClear( GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT );
232 /* Tell GL we are switching to model view parameters */
233 glMatrixMode(GL_MODELVIEW);
234 /* glLoadIdentity(); */
245 /**************************************************************************
246 * Update internal time dependent calculations (i.e. flight model)
247 **************************************************************************/
249 void fgUpdateTimeDepCalcs(int multi_loop) {
250 struct flight_params *f;
253 f = ¤t_aircraft.flight;
255 /* update the flight model */
256 if ( multi_loop < 0 ) {
257 multi_loop = DEFAULT_MULTILOOP;
260 /* printf("updating flight model x %d\n", multi_loop); */
261 fgFlightModelUpdate(FG_LARCSIM, f, multi_loop);
263 for ( i = 0; i < multi_loop; i++ ) {
264 if ( fabs(goal_view_offset - view_offset) < 0.05 ) {
265 view_offset = goal_view_offset;
268 /* move view_offset towards goal_view_offset */
269 if ( goal_view_offset > view_offset ) {
270 if ( goal_view_offset - view_offset < FG_PI ) {
276 if ( view_offset - goal_view_offset < FG_PI ) {
282 if ( view_offset > FG_2PI ) {
283 view_offset -= FG_2PI;
284 } else if ( view_offset < 0 ) {
285 view_offset += FG_2PI;
292 void fgInitTimeDepCalcs() {
293 /* initialize timer */
296 fgTimerInit( 1.0 / DEFAULT_TIMER_HZ, fgUpdateTimeDepCalcs );
302 /**************************************************************************
303 * Scenery management routines
304 **************************************************************************/
306 /* static void fgSceneryInit_OLD() { */
308 /* scenery = fgSceneryCompile_OLD();
309 runway = fgRunwayHack_OLD(0.69, 53.07);
313 /* create the scenery */
314 /* GLint fgSceneryCompile_OLD() {
317 scenery = mesh2GL(mesh_ptr_OLD);
323 /* hack in a runway */
324 /* GLint fgRunwayHack_OLD(double width, double length) {
325 static GLfloat concrete[4] = { 0.5, 0.5, 0.5, 1.0 };
326 static GLfloat line[4] = { 0.9, 0.9, 0.9, 1.0 };
329 float line_len, line_width_2, cur_pos;
331 runway = glGenLists(1);
332 glNewList(runway, GL_COMPILE);
335 /* glBegin(GL_POLYGON);
336 glMaterialfv( GL_FRONT, GL_AMBIENT_AND_DIFFUSE, concrete );
337 glNormal3f(0.0, 0.0, 1.0);
339 glVertex3d( 0.0, -width/2.0, 0.0);
340 glVertex3d( 0.0, width/2.0, 0.0);
341 glVertex3d(length, width/2.0, 0.0);
342 glVertex3d(length, -width/2.0, 0.0);
345 /* draw center line */
346 /* glMaterialfv( GL_FRONT, GL_AMBIENT_AND_DIFFUSE, line );
347 line_len = length / ( 2 * num_lines + 1);
348 printf("line_len = %.3f\n", line_len);
351 for ( i = 0; i < num_lines; i++ ) {
353 glVertex3d( cur_pos, -line_width_2, 0.005);
354 glVertex3d( cur_pos, line_width_2, 0.005);
356 glVertex3d( cur_pos, line_width_2, 0.005);
357 glVertex3d( cur_pos, -line_width_2, 0.005);
368 /* draw the scenery */
369 /*static void fgSceneryDraw_OLD() {
370 static float z = 32.35;
376 printf("*** Drawing runway at %.2f\n", z);
378 glTranslatef( -398391.28, 120070.41, 32.35);
379 glRotatef(170.0, 0.0, 0.0, 1.0);
386 /* What should we do when we have nothing else to do? How about get
387 * ready for the next move and update the display? */
388 static void fgMainLoop( void ) {
389 static int remainder = 0;
390 int elapsed, multi_loop;
392 struct flight_params *f;
394 f = ¤t_aircraft.flight;
396 elapsed = fgGetTimeInterval();
397 printf("Time interval is = %d, previous remainder is = %d\n", elapsed,
399 printf("--> Frame rate is = %.2f\n", 1000.0 / (float)elapsed);
400 elapsed += remainder;
402 multi_loop = ((float)elapsed * 0.001) * DEFAULT_MODEL_HZ;
403 remainder = elapsed - ((multi_loop*1000) / DEFAULT_MODEL_HZ);
404 printf("Model iterations needed = %d, new remainder = %d\n", multi_loop,
410 if ( ! use_signals ) {
412 fgUpdateTimeDepCalcs(multi_loop);
415 /* I'm just sticking this here for now, it should probably move
417 rough_elev = mesh_altitude(FG_Longitude * RAD_TO_ARCSEC,
418 FG_Latitude * RAD_TO_ARCSEC);
419 printf("Ground elevation is %.2f meters here.\n", rough_elev);
420 /* FG_Runway_altitude = rough_elev * METER_TO_FEET; */
422 if ( FG_Altitude * FEET_TO_METER < rough_elev + 3.758099) {
423 /* set this here, otherwise if we set runway height above our
424 current height we get a really nasty bounce. */
425 FG_Runway_altitude = FG_Altitude - 3.758099;
427 /* now set aircraft altitude above ground */
428 FG_Altitude = rough_elev * METER_TO_FEET + 3.758099;
429 printf("<*> resetting altitude to %.0f meters\n",
430 FG_Altitude * FEET_TO_METER);
433 /* update the weather for our current position */
434 fgWeatherUpdate(FG_Longitude * RAD_TO_ARCSEC,
435 FG_Latitude * RAD_TO_ARCSEC,
436 FG_Altitude * FEET_TO_METER);
440 /**************************************************************************
441 * Handle new window size or exposure
442 **************************************************************************/
444 static void fgReshape( int width, int height ) {
445 /* Do this so we can call fgReshape(0,0) ourselves without having to know
446 * what the values of width & height are. */
447 if ( (height > 0) && (width > 0) ) {
448 win_ratio = (GLfloat) height / (GLfloat) width;
451 /* Inform gl of our view window size */
452 glViewport(0, 0, (GLint)width, (GLint)height);
454 fgUpdateViewParams();
456 glClear( GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT );
460 /**************************************************************************
462 **************************************************************************/
464 int main( int argc, char *argv[] ) {
465 struct flight_params *f;
468 f = ¤t_aircraft.flight;
470 printf("Flight Gear: prototype code to test OpenGL, LaRCsim, and VRML\n\n");
473 /**********************************************************************
474 * Initialize the Window/Graphics environment.
475 **********************************************************************/
478 /* initialize GLUT */
479 glutInit(&argc, argv);
481 /* Define Display Parameters */
482 glutInitDisplayMode( GLUT_RGB | GLUT_DEPTH | GLUT_DOUBLE );
484 /* Define initial window size */
485 glutInitWindowSize(640, 480);
487 /* Initialize windows */
488 glutCreateWindow("Flight Gear");
491 /* seed the random number generater */
494 /* setup view parameters, only makes GL calls */
498 /****************************************************************
499 * The following section sets up the flight model EOM parameters and
500 * should really be read in from one or more files.
501 ****************************************************************/
503 /* Globe Aiport, AZ */
504 FG_Runway_altitude = 3234.5;
505 FG_Runway_latitude = 120070.41;
506 FG_Runway_longitude = -398391.28;
507 FG_Runway_heading = 102.0 * DEG_TO_RAD;
509 /* Initial Position */
510 FG_Latitude = ( 120070.41 / 3600.0 ) * DEG_TO_RAD;
511 FG_Longitude = ( -398391.28 / 3600.0 ) * DEG_TO_RAD;
512 FG_Altitude = FG_Runway_altitude + 3.758099;
514 /* FG_Latitude = 0.0; */
515 /* FG_Longitude = 0.0; */
516 /* FG_Altitude = 15000.0; */
518 printf("Initial position is: (%.4f, %.4f, %.2f)\n", FG_Latitude,
519 FG_Longitude, FG_Altitude);
521 /* Initial Velocity */
522 FG_V_north = 0.0 /* 7.287719E+00 */;
523 FG_V_east = 0.0 /* 1.521770E+03 */;
524 FG_V_down = 0.0 /* -1.265722E-05 */;
526 /* Initial Orientation */
527 FG_Phi = -2.658474E-06;
528 FG_Theta = 7.401790E-03;
529 /* FG_Psi = 270.0 * DEG_TO_RAD; */
530 FG_Psi = 0.0 * DEG_TO_RAD;
532 /* Initial Angular B rates */
533 FG_P_body = 7.206685E-05;
534 FG_Q_body = 0.000000E+00;
535 FG_R_body = 9.492658E-05;
537 FG_Earth_position_angle = 0.000000E+00;
539 /* Mass properties and geometry values */
540 FG_Mass = 8.547270E+01;
541 FG_I_xx = 1.048000E+03;
542 FG_I_yy = 3.000000E+03;
543 FG_I_zz = 3.530000E+03;
544 FG_I_xz = 0.000000E+00;
546 /* CG position w.r.t. ref. point */
547 FG_Dx_cg = 0.000000E+00;
548 FG_Dy_cg = 0.000000E+00;
549 FG_Dz_cg = 0.000000E+00;
551 /* Set initial position and slew parameters */
552 /* fgSlewInit(-398391.3, 120070.41, 244, 3.1415); */ /* GLOBE Airport */
553 /* fgSlewInit(-335340,162540, 15, 4.38); */
554 /* fgSlewInit(-398673.28,120625.64, 53, 4.38); */
556 /* Initialize the Scenery Management system */
559 /* Tell the Scenery Management system where we are so it can load
560 * the correct scenery data */
561 fgSceneryUpdate(FG_Latitude, FG_Longitude, FG_Altitude);
563 /* I'm just sticking this here for now, it should probably move
565 rough_elev = mesh_altitude(FG_Longitude * RAD_TO_DEG * 3600.0,
566 FG_Latitude * RAD_TO_DEG * 3600.0);
567 printf("Ground elevation is %.2f meters here.\n", rough_elev);
568 if ( rough_elev > -9990.0 ) {
569 FG_Runway_altitude = rough_elev * METER_TO_FEET;
572 if ( FG_Altitude < FG_Runway_altitude ) {
573 FG_Altitude = FG_Runway_altitude + 3.758099;
575 /* end of thing that I just stuck in that I should probably move */
577 /* Initialize the flight model data structures base on above values */
578 fgFlightModelInit( FG_LARCSIM, f, 1.0 / DEFAULT_MODEL_HZ );
581 /* init timer routines, signals, etc. Arrange for an alarm
582 signal to be generated, etc. */
583 fgInitTimeDepCalcs();
586 /* Initialize the weather modeling subsystem */
589 /**********************************************************************
590 * Initialize the Event Handlers.
591 **********************************************************************/
594 /* call fgReshape() on window resizes */
595 glutReshapeFunc( fgReshape );
597 /* call key() on keyboard event */
598 glutKeyboardFunc( GLUTkey );
599 glutSpecialFunc( GLUTspecialkey );
601 /* call fgMainLoop() whenever there is nothing else to do */
602 glutIdleFunc( fgMainLoop );
605 glutDisplayFunc( fgUpdateVisuals );
607 /* pass control off to the GLUT event handler */
617 int printf (const char *format, ...) {
623 /* Revision 1.2 1997/08/04 20:25:15 curt
624 /* Organizational tweaking.
626 * Revision 1.1 1997/08/02 18:45:00 curt
627 * Renamed GLmain.c GLUTmain.c
629 * Revision 1.43 1997/08/02 16:23:47 curt
632 * Revision 1.42 1997/08/01 19:43:33 curt
633 * Making progress with coordinate system overhaul.
635 * Revision 1.41 1997/07/31 22:52:37 curt
636 * Working on redoing internal coordinate systems & scenery transformations.
638 * Revision 1.40 1997/07/30 16:12:42 curt
639 * Moved fg_random routines from Util/ to Math/
641 * Revision 1.39 1997/07/21 14:45:01 curt
644 * Revision 1.38 1997/07/19 23:04:47 curt
645 * Added an initial weather section.
647 * Revision 1.37 1997/07/19 22:34:02 curt
648 * Moved PI definitions to ../constants.h
649 * Moved random() stuff to ../Utils/ and renamed fg_random()
651 * Revision 1.36 1997/07/18 23:41:25 curt
652 * Tweaks for building with Cygnus Win32 compiler.
654 * Revision 1.35 1997/07/18 14:28:34 curt
655 * Hacked in some support for wind/turbulence.
657 * Revision 1.34 1997/07/16 20:04:48 curt
658 * Minor tweaks to aid Win32 port.
660 * Revision 1.33 1997/07/12 03:50:20 curt
661 * Added an #include <Windows32/Base.h> to help compiling for Win32
663 * Revision 1.32 1997/07/11 03:23:18 curt
664 * Solved some scenery display/orientation problems. Still have a positioning
665 * (or transformation?) problem.
667 * Revision 1.31 1997/07/11 01:29:58 curt
668 * More tweaking of terrian floor.
670 * Revision 1.30 1997/07/10 04:26:37 curt
671 * We now can interpolated ground elevation for any position in the grid. We
672 * can use this to enforce a "hard" ground. We still need to enforce some
673 * bounds checking so that we don't try to lookup data points outside the
676 * Revision 1.29 1997/07/09 21:31:12 curt
677 * Working on making the ground "hard."
679 * Revision 1.28 1997/07/08 18:20:12 curt
680 * Working on establishing a hard ground.
682 * Revision 1.27 1997/07/07 20:59:49 curt
683 * Working on scenery transformations to enable us to fly fluidly over the
684 * poles with no discontinuity/distortion in scenery.
686 * Revision 1.26 1997/07/05 20:43:34 curt
687 * renamed mat3 directory to Math so we could add other math related routines.
689 * Revision 1.25 1997/06/29 21:19:17 curt
690 * Working on scenery management system.
692 * Revision 1.24 1997/06/26 22:14:53 curt
693 * Beginning work on a scenery management system.
695 * Revision 1.23 1997/06/26 19:08:33 curt
696 * Restructuring make, adding automatic "make dep" support.
698 * Revision 1.22 1997/06/25 15:39:47 curt
699 * Minor changes to compile with rsxnt/win32.
701 * Revision 1.21 1997/06/22 21:44:41 curt
702 * Working on intergrating the VRML (subset) parser.
704 * Revision 1.20 1997/06/21 17:12:53 curt
705 * Capitalized subdirectory names.
707 * Revision 1.19 1997/06/18 04:10:31 curt
708 * A couple more runway tweaks ...
710 * Revision 1.18 1997/06/18 02:21:24 curt
713 * Revision 1.17 1997/06/17 16:51:58 curt
714 * Timer interval stuff now uses gettimeofday() instead of ftime()
716 * Revision 1.16 1997/06/17 04:19:16 curt
717 * More timer related tweaks with respect to view direction changes.
719 * Revision 1.15 1997/06/17 03:41:10 curt
720 * Nonsignal based interval timing is now working.
721 * This would be a good time to look at cleaning up the code structure a bit.
723 * Revision 1.14 1997/06/16 19:32:51 curt
724 * Starting to add general timer support.
726 * Revision 1.13 1997/06/02 03:40:06 curt
727 * A tiny bit more view tweaking.
729 * Revision 1.12 1997/06/02 03:01:38 curt
730 * Working on views (side, front, back, transitions, etc.)
732 * Revision 1.11 1997/05/31 19:16:25 curt
733 * Elevator trim added.
735 * Revision 1.10 1997/05/31 04:13:52 curt
738 * Continuing work on the LaRCsim flight model integration.
739 * Added some MSFS-like keyboard input handling.
741 * Revision 1.9 1997/05/30 19:27:01 curt
742 * The LaRCsim flight model is starting to look like it is working.
744 * Revision 1.8 1997/05/30 03:54:10 curt
745 * Made a bit more progress towards integrating the LaRCsim flight model.
747 * Revision 1.7 1997/05/29 22:39:49 curt
748 * Working on incorporating the LaRCsim flight model.
750 * Revision 1.6 1997/05/29 12:31:39 curt
751 * Minor tweaks, moving towards general flight model integration.
753 * Revision 1.5 1997/05/29 02:33:23 curt
754 * Updated to reflect changing interfaces in other "modules."
756 * Revision 1.4 1997/05/27 17:44:31 curt
757 * Renamed & rearranged variables and routines. Added some initial simple
758 * timer/alarm routines so the flight model can be updated on a regular
761 * Revision 1.3 1997/05/23 15:40:25 curt
762 * Added GNU copyright headers.
765 * Revision 1.2 1997/05/23 00:35:12 curt
766 * Trying to get fog to work ...
768 * Revision 1.1 1997/05/21 15:57:51 curt
769 * Renamed due to added GLUT support.
771 * Revision 1.3 1997/05/19 18:22:42 curt
772 * Parameter tweaking ... starting to stub in fog support.
774 * Revision 1.2 1997/05/17 00:17:34 curt
775 * Trying to stub in support for standard OpenGL.
777 * Revision 1.1 1997/05/16 16:05:52 curt