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 **************************************************************************/
35 /* assumes -I/usr/include/mesa in compile command */
40 #include "../aircraft/aircraft.h"
41 #include "../scenery/scenery.h"
42 #include "../mat3/mat3.h"
43 #include "../timer/fg_timer.h"
46 #define DEG_TO_RAD 0.017453292
47 #define RAD_TO_DEG 57.29577951
50 #define PI2 (M_PI + M_PI)
53 /* This is a record containing all the info for the aircraft currently
55 struct aircraft_params current_aircraft;
58 static GLfloat win_ratio = 1.0;
61 static GLfloat sun_vec[4] = {-3.0, 1.0, 2.0, 0.0 };
64 extern struct mesh *mesh_ptr;
65 /* Function prototypes */
66 GLint fgSceneryCompile();
67 static void fgSceneryDraw();
68 /* pointer to terrain mesh structure */
69 static GLint terrain, runway;
72 double fogDensity = 2000.0;
73 double view_offset = 0.0;
74 double goal_view_offset = 0.0;
77 #define DEFAULT_TIMER_HZ 20
78 #define DEFAULT_MULTILOOP 6
79 #define DEFAULT_MODEL_HZ (DEFAULT_TIMER_HZ * DEFAULT_MULTILOOP)
87 /**************************************************************************
88 * fgInitVisuals() -- Initialize various GL/view parameters
89 **************************************************************************/
91 static void fgInitVisuals() {
92 /* if the 4th field is 0.0, this specifies a direction ... */
93 static GLfloat fogColor[4] = {0.65, 0.65, 0.85, 1.0};
95 glEnable( GL_DEPTH_TEST );
97 glEnable( GL_CULL_FACE );
99 /* If enabled, normal vectors specified with glNormal are scaled
100 to unit length after transformation. See glNormal. */
101 glEnable( GL_NORMALIZE );
103 glLightfv( GL_LIGHT0, GL_POSITION, sun_vec );
104 glEnable( GL_LIGHTING );
105 glEnable( GL_LIGHT0 );
107 glShadeModel( GL_FLAT ); /* glShadeModel( GL_SMOOTH ); */
110 glFogi (GL_FOG_MODE, GL_LINEAR);
111 /* glFogf (GL_FOG_START, 1.0); */
112 glFogf (GL_FOG_END, fogDensity);
113 glFogfv (GL_FOG_COLOR, fogColor);
114 /* glFogf (GL_FOG_DENSITY, fogDensity); */
115 /* glHint (GL_FOG_HINT, GL_FASTEST); */
117 glClearColor(0.6, 0.6, 0.9, 1.0);
121 /**************************************************************************
122 * Update the view volume, position, and orientation
123 **************************************************************************/
125 static void fgUpdateViewParams() {
126 double pos_x, pos_y, pos_z;
127 struct flight_params *f;
129 MAT3vec vec, up, forward, fwrd_view;
131 f = ¤t_aircraft.flight;
133 /* Tell GL we are about to modify the projection parameters */
134 glMatrixMode(GL_PROJECTION);
136 gluPerspective(45.0, 1.0/win_ratio, 0.01, 6000.0);
138 glMatrixMode(GL_MODELVIEW);
141 /* calculate position in arc seconds */
142 pos_x = (FG_Longitude * RAD_TO_DEG) * 3600.0;
143 pos_y = (FG_Latitude * RAD_TO_DEG) * 3600.0;
144 pos_z = FG_Altitude * 0.01; /* (Convert feet to aproximate arcsecs) */
146 printf("*** pos_z = %.2f\n", pos_z);
148 /* build current rotation matrix */
149 MAT3_SET_VEC(vec, 1.0, 0.0, 0.0);
150 MAT3rotate(R, vec, FG_Phi);
151 /* printf("Roll matrix\n"); */
152 /* MAT3print(R, stdout); */
154 MAT3_SET_VEC(vec, 0.0, 1.0, 0.0);
155 /* MAT3mult_vec(vec, vec, R); */
156 MAT3rotate(TMP, vec, -FG_Theta);
157 /* printf("Pitch matrix\n"); */
158 /* MAT3print(TMP, stdout); */
161 MAT3_SET_VEC(vec, 0.0, 0.0, -1.0);
162 /* MAT3mult_vec(vec, vec, R); */
163 /* MAT3rotate(TMP, vec, M_PI + M_PI_2 + FG_Psi + view_offset); */
164 MAT3rotate(TMP, vec, FG_Psi - M_PI_2);
165 /* printf("Yaw matrix\n");
166 MAT3print(TMP, stdout); */
169 /* MAT3print(R, stdout); */
171 /* generate the current up, forward, and fwrd-view vectors */
172 MAT3_SET_VEC(vec, 0.0, 0.0, 1.0);
173 MAT3mult_vec(up, vec, R);
175 MAT3_SET_VEC(vec, 1.0, 0.0, 0.0);
176 MAT3mult_vec(forward, vec, R);
177 printf("Forward vector is (%.2f,%.2f,%.2f)\n", forward[0], forward[1],
180 MAT3rotate(TMP, up, view_offset);
181 MAT3mult_vec(fwrd_view, forward, TMP);
183 gluLookAt(pos_x, pos_y, pos_z,
184 pos_x + fwrd_view[0], pos_y + fwrd_view[1], pos_z + fwrd_view[2],
185 up[0], up[1], up[2]);
187 glLightfv( GL_LIGHT0, GL_POSITION, sun_vec );
191 /**************************************************************************
192 * Update all Visuals (redraws anything graphics related)
193 **************************************************************************/
195 static void fgUpdateVisuals( void ) {
196 /* update view volume parameters */
197 fgUpdateViewParams();
199 glClear( GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT );
201 /* Tell GL we are switching to model view parameters */
202 glMatrixMode(GL_MODELVIEW);
203 /* glLoadIdentity(); */
205 /* draw terrain mesh */
216 /**************************************************************************
217 * Update internal time dependent calculations (i.e. flight model)
218 **************************************************************************/
220 void fgUpdateTimeDepCalcs(int multi_loop) {
221 struct flight_params *f;
224 f = ¤t_aircraft.flight;
226 /* update the flight model */
227 if ( multi_loop < 0 ) {
228 multi_loop = DEFAULT_MULTILOOP;
231 /* printf("updating flight model x %d\n", multi_loop); */
232 fgFlightModelUpdate(FG_LARCSIM, f, multi_loop);
234 for ( i = 0; i < multi_loop; i++ ) {
235 if ( fabs(goal_view_offset - view_offset) < 0.05 ) {
236 view_offset = goal_view_offset;
239 /* move view_offset towards goal_view_offset */
240 if ( goal_view_offset > view_offset ) {
241 if ( goal_view_offset - view_offset < M_PI ) {
247 if ( view_offset - goal_view_offset < M_PI ) {
253 if ( view_offset > PI2 ) {
255 } else if ( view_offset < 0 ) {
263 void fgInitTimeDepCalcs() {
264 /* initialize timer */
265 fgTimerInit( 1.0 / DEFAULT_TIMER_HZ, fgUpdateTimeDepCalcs );
269 /**************************************************************************
270 * Scenery management routines
271 **************************************************************************/
273 static void fgSceneryInit() {
274 /* make terrain mesh */
275 terrain = fgSceneryCompile();
276 runway = fgRunwayHack(0.69, 53.07);
280 /* create the terrain mesh */
281 GLint fgSceneryCompile() {
284 terrain = mesh2GL(mesh_ptr);
290 /* hack in a runway */
291 GLint fgRunwayHack(double width, double length) {
292 static GLfloat concrete[4] = { 0.5, 0.5, 0.5, 1.0 };
293 static GLfloat line[4] = { 0.9, 0.9, 0.9, 1.0 };
296 float line_len, line_width_2, cur_pos;
298 runway = glGenLists(1);
299 glNewList(runway, GL_COMPILE);
303 glMaterialfv( GL_FRONT, GL_AMBIENT_AND_DIFFUSE, concrete );
304 glNormal3f(0.0, 0.0, 1.0);
306 glVertex3d( 0.0, -width/2.0, 0.0);
307 glVertex3d( 0.0, width/2.0, 0.0);
308 glVertex3d(length, width/2.0, 0.0);
309 glVertex3d(length, -width/2.0, 0.0);
312 /* draw center line */
313 glMaterialfv( GL_FRONT, GL_AMBIENT_AND_DIFFUSE, line );
314 line_len = length / ( 2 * num_lines + 1);
315 printf("line_len = %.3f\n", line_len);
318 for ( i = 0; i < num_lines; i++ ) {
320 glVertex3d( cur_pos, -line_width_2, 0.005);
321 glVertex3d( cur_pos, line_width_2, 0.005);
323 glVertex3d( cur_pos, line_width_2, 0.005);
324 glVertex3d( cur_pos, -line_width_2, 0.005);
335 /* draw the terrain mesh */
336 static void fgSceneryDraw() {
337 static float z = 32.35;
342 printf("*** Drawing runway at %.2f\n", z);
344 glTranslatef( -398391.28, 120070.41, z);
345 glRotatef(170.0, 0.0, 0.0, 1.0);
350 /* What should we do when we have nothing else to do? How about get
351 * ready for the next move?*/
352 static void fgMainLoop( void ) {
353 static int remainder = 0;
354 int elapsed, multi_loop;
356 elapsed = fgGetTimeInterval();
357 printf("Time interval is = %d, previous remainder is = %d\n", elapsed,
359 printf("--> Frame rate is = %.2f\n", 1000.0 / (float)elapsed);
360 elapsed += remainder;
362 multi_loop = ((float)elapsed * 0.001) * DEFAULT_MODEL_HZ;
363 remainder = elapsed - ((multi_loop*1000) / DEFAULT_MODEL_HZ);
364 printf("Model iterations needed = %d, new remainder = %d\n", multi_loop,
370 if ( ! use_signals ) {
371 fgUpdateTimeDepCalcs(multi_loop);
376 /**************************************************************************
377 * Handle new window size or exposure
378 **************************************************************************/
380 static void fgReshape( int width, int height ) {
381 /* Do this so we can call fgReshape(0,0) ourselves without having to know
382 * what the values of width & height are. */
383 if ( (height > 0) && (width > 0) ) {
384 win_ratio = (GLfloat) height / (GLfloat) width;
387 /* Inform gl of our view window size */
388 glViewport(0, 0, (GLint)width, (GLint)height);
390 fgUpdateViewParams();
392 glClear( GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT );
396 /**************************************************************************
398 **************************************************************************/
400 int main( int argc, char *argv[] ) {
401 struct flight_params *f;
403 f = ¤t_aircraft.flight;
405 /* parse the scenery file */
406 parse_scenery(argv[1]);
409 /* initialize GLUT */
410 glutInit(&argc, argv);
412 /* Define Display Parameters */
413 glutInitDisplayMode( GLUT_RGB | GLUT_DEPTH | GLUT_DOUBLE );
415 /* Define initial window size */
416 glutInitWindowSize(640, 480);
418 /* Initialize the main window */
419 glutCreateWindow("Terrain Demo");
421 /* Define initial window size */
422 tkInitPosition(0, 0, 640, 480);
424 /* Define Display Parameters */
425 tkInitDisplayMode( TK_RGB | TK_DEPTH | TK_DOUBLE | TK_DIRECT );
427 /* Initialize the main window */
428 if (tkInitWindow("Terrain Demo") == GL_FALSE) {
433 /* setup view parameters, only makes GL calls */
436 /* Globe Aiport, AZ */
437 FG_Runway_altitude = 3234.5;
438 FG_Runway_latitude = 120070.41;
439 FG_Runway_longitude = -398391.28;
440 FG_Runway_heading = 102.0 * DEG_TO_RAD;
442 /* Initial Position */
443 FG_Latitude = ( 120070.41 / 3600.0 ) * DEG_TO_RAD;
444 FG_Longitude = ( -398391.28 / 3600.0 ) * DEG_TO_RAD;
445 FG_Altitude = FG_Runway_altitude + 3.758099;
447 printf("Initial position is: (%.4f, %.4f, %.2f)\n", FG_Latitude,
448 FG_Longitude, FG_Altitude);
451 /* Initial Velocity */
452 FG_V_north = 0.0 /* 7.287719E+00 */;
453 FG_V_east = 0.0 /* 1.521770E+03 */;
454 FG_V_down = 0.0 /* -1.265722E-05 */;
456 /* Initial Orientation */
457 FG_Phi = -2.658474E-06;
458 FG_Theta = 7.401790E-03;
459 FG_Psi = 282.0 * DEG_TO_RAD;
461 /* Initial Angular B rates */
462 FG_P_body = 7.206685E-05;
463 FG_Q_body = 0.000000E+00;
464 FG_R_body = 9.492658E-05;
466 FG_Earth_position_angle = 0.000000E+00;
468 /* Mass properties and geometry values */
469 FG_Mass = 8.547270E+01;
470 FG_I_xx = 1.048000E+03;
471 FG_I_yy = 3.000000E+03;
472 FG_I_zz = 3.530000E+03;
473 FG_I_xz = 0.000000E+00;
475 /* CG position w.r.t. ref. point */
476 FG_Dx_cg = 0.000000E+00;
477 FG_Dy_cg = 0.000000E+00;
478 FG_Dz_cg = 0.000000E+00;
480 /* Set initial position and slew parameters */
481 /* fgSlewInit(-398391.3, 120070.41, 244, 3.1415); */ /* GLOBE Airport */
482 /* fgSlewInit(-335340,162540, 15, 4.38); */
483 /* fgSlewInit(-398673.28,120625.64, 53, 4.38); */
485 fgFlightModelInit( FG_LARCSIM, f, 1.0 / DEFAULT_MODEL_HZ );
488 /* init timer routines, signals, etc. Arrange for an alarm
489 signal to be generated, etc. */
490 fgInitTimeDepCalcs();
493 /* build all objects */
497 /* call fgReshape() on window resizes */
498 glutReshapeFunc( fgReshape );
500 /* call key() on keyboard event */
501 glutKeyboardFunc( GLUTkey );
502 glutSpecialFunc( GLUTspecialkey );
504 /* call fgMainLoop() whenever there is nothing else to do */
505 glutIdleFunc( fgMainLoop );
508 glutDisplayFunc( fgUpdateVisuals );
510 /* pass control off to the GLUT event handler */
513 /* call fgReshape() on expose events */
514 tkExposeFunc( fgReshape );
516 /* call fgReshape() on window resizes */
517 tkReshapeFunc( fgReshape );
519 /* call key() on keyboard event */
520 tkKeyDownFunc( GLTKkey );
522 /* call fgMainLoop() whenever there is nothing else to do */
523 tkIdleFunc( fgMainLoop );
526 tkDisplayFunc( fgUpdateVisuals );
528 /* pass control off to the tk event handler */
537 /* Revision 1.19 1997/06/18 04:10:31 curt
538 /* A couple more runway tweaks ...
540 * Revision 1.18 1997/06/18 02:21:24 curt
543 * Revision 1.17 1997/06/17 16:51:58 curt
544 * Timer interval stuff now uses gettimeofday() instead of ftime()
546 * Revision 1.16 1997/06/17 04:19:16 curt
547 * More timer related tweaks with respect to view direction changes.
549 * Revision 1.15 1997/06/17 03:41:10 curt
550 * Nonsignal based interval timing is now working.
551 * This would be a good time to look at cleaning up the code structure a bit.
553 * Revision 1.14 1997/06/16 19:32:51 curt
554 * Starting to add general timer support.
556 * Revision 1.13 1997/06/02 03:40:06 curt
557 * A tiny bit more view tweaking.
559 * Revision 1.12 1997/06/02 03:01:38 curt
560 * Working on views (side, front, back, transitions, etc.)
562 * Revision 1.11 1997/05/31 19:16:25 curt
563 * Elevator trim added.
565 * Revision 1.10 1997/05/31 04:13:52 curt
568 * Continuing work on the LaRCsim flight model integration.
569 * Added some MSFS-like keyboard input handling.
571 * Revision 1.9 1997/05/30 19:27:01 curt
572 * The LaRCsim flight model is starting to look like it is working.
574 * Revision 1.8 1997/05/30 03:54:10 curt
575 * Made a bit more progress towards integrating the LaRCsim flight model.
577 * Revision 1.7 1997/05/29 22:39:49 curt
578 * Working on incorporating the LaRCsim flight model.
580 * Revision 1.6 1997/05/29 12:31:39 curt
581 * Minor tweaks, moving towards general flight model integration.
583 * Revision 1.5 1997/05/29 02:33:23 curt
584 * Updated to reflect changing interfaces in other "modules."
586 * Revision 1.4 1997/05/27 17:44:31 curt
587 * Renamed & rearranged variables and routines. Added some initial simple
588 * timer/alarm routines so the flight model can be updated on a regular
591 * Revision 1.3 1997/05/23 15:40:25 curt
592 * Added GNU copyright headers.
595 * Revision 1.2 1997/05/23 00:35:12 curt
596 * Trying to get fog to work ...
598 * Revision 1.1 1997/05/21 15:57:51 curt
599 * Renamed due to added GLUT support.
601 * Revision 1.3 1997/05/19 18:22:42 curt
602 * Parameter tweaking ... starting to stub in fog support.
604 * Revision 1.2 1997/05/17 00:17:34 curt
605 * Trying to stub in support for standard OpenGL.
607 * Revision 1.1 1997/05/16 16:05:52 curt