1 // views.cxx -- data structures and routines for managing and view
4 // Written by Curtis Olson, started August 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)
30 #include <Debug/fg_debug.h>
31 #include <Flight/flight.h>
32 #include <Include/fg_constants.h>
33 #include <Math/mat3.h>
34 #include <Math/polar3d.hxx>
35 #include <Math/vector.hxx>
36 #include <Scenery/scenery.hxx>
37 #include <Time/fg_time.hxx>
39 #include "options.hxx"
43 // This is a record containing current view parameters
48 fgVIEW::fgVIEW( void ) {
52 // Initialize a view structure
53 void fgVIEW::Init( void ) {
54 fgPrintf( FG_VIEW, FG_INFO, "Initializing View parameters\n");
57 goal_view_offset = 0.0;
59 winWidth = 640; // FG_DEFAULT_WIN_WIDTH
60 winHeight = 480; // FG_DEFAULT_WIN_HEIGHT
61 win_ratio = (double) winWidth / (double) winHeight;
66 // Update the field of view parameters
67 void fgVIEW::UpdateFOV( fgOPTIONS *o ) {
68 double fov, theta_x, theta_y;
72 // printf("win_ratio = %.2f\n", win_ratio);
73 // calculate sin() and cos() of fov / 2 in X direction;
74 theta_x = (fov * win_ratio * DEG_TO_RAD) / 2.0;
75 // printf("theta_x = %.2f\n", theta_x);
76 sin_fov_x = sin(theta_x);
77 cos_fov_x = cos(theta_x);
78 slope_x = - cos_fov_x / sin_fov_x;
79 // printf("slope_x = %.2f\n", slope_x);
81 // calculate sin() and cos() of fov / 2 in Y direction;
82 theta_y = (fov * DEG_TO_RAD) / 2.0;
83 // printf("theta_y = %.2f\n", theta_y);
84 sin_fov_y = sin(theta_y);
85 cos_fov_y = cos(theta_y);
86 slope_y = cos_fov_y / sin_fov_y;
87 // printf("slope_y = %.2f\n", slope_y);
91 // Update the view parameters
92 void fgVIEW::Update( fgFLIGHT *f ) {
94 MAT3vec vec, forward, v0, minus_z;
95 MAT3mat R, TMP, UP, LOCAL, VIEW;
98 if(update_fov == TRUE) {
99 // printf("Updating fov\n");
100 UpdateFOV(¤t_options);
104 scenery.center.x = scenery.next_center.x;
105 scenery.center.y = scenery.next_center.y;
106 scenery.center.z = scenery.next_center.z;
108 // printf("scenery center = %.2f %.2f %.2f\n", scenery.center.x,
109 // scenery.center.y, scenery.center.z);
111 // calculate the cartesion coords of the current lat/lon/0 elev
112 p.lon = FG_Longitude;
113 p.lat = FG_Lat_geocentric;
114 p.radius = FG_Sea_level_radius * FEET_TO_METER;
116 cur_zero_elev = fgPolarToCart3d(p);
118 cur_zero_elev.x -= scenery.center.x;
119 cur_zero_elev.y -= scenery.center.y;
120 cur_zero_elev.z -= scenery.center.z;
122 // calculate view position in current FG view coordinate system
123 // p.lon & p.lat are already defined earlier, p.radius was set to
124 // the sea level radius, so now we add in our altitude.
125 if ( FG_Altitude * FEET_TO_METER >
126 (scenery.cur_elev + 3.758099 * METER_TO_FEET) ) {
127 p.radius += FG_Altitude * FEET_TO_METER;
129 p.radius += scenery.cur_elev + 3.758099 * METER_TO_FEET;
132 abs_view_pos = fgPolarToCart3d(p);
134 view_pos.x = abs_view_pos.x - scenery.center.x;
135 view_pos.y = abs_view_pos.y - scenery.center.y;
136 view_pos.z = abs_view_pos.z - scenery.center.z;
138 fgPrintf( FG_VIEW, FG_DEBUG, "Absolute view pos = %.4f, %.4f, %.4f\n",
139 abs_view_pos.x, abs_view_pos.y, abs_view_pos.z);
140 fgPrintf( FG_VIEW, FG_DEBUG, "Relative view pos = %.4f, %.4f, %.4f\n",
141 view_pos.x, view_pos.y, view_pos.z);
143 // Derive the LOCAL aircraft rotation matrix (roll, pitch, yaw)
144 // from FG_T_local_to_body[3][3]
146 // Question: Why is the LaRCsim matrix arranged so differently
147 // than the one we need???
148 LOCAL[0][0] = FG_T_local_to_body_33;
149 LOCAL[0][1] = -FG_T_local_to_body_32;
150 LOCAL[0][2] = -FG_T_local_to_body_31;
152 LOCAL[1][0] = -FG_T_local_to_body_23;
153 LOCAL[1][1] = FG_T_local_to_body_22;
154 LOCAL[1][2] = FG_T_local_to_body_21;
156 LOCAL[2][0] = -FG_T_local_to_body_13;
157 LOCAL[2][1] = FG_T_local_to_body_12;
158 LOCAL[2][2] = FG_T_local_to_body_11;
160 LOCAL[3][0] = LOCAL[3][1] = LOCAL[3][2] = LOCAL[3][3] = 0.0;
162 // printf("LaRCsim LOCAL matrix\n");
163 // MAT3print(LOCAL, stdout);
165 #ifdef OLD_LOCAL_TO_BODY_CODE
166 // old code to calculate LOCAL matrix calculated from Phi,
167 // Theta, and Psi (roll, pitch, yaw)
169 MAT3_SET_VEC(vec, 0.0, 0.0, 1.0);
170 MAT3rotate(R, vec, FG_Phi);
171 /* printf("Roll 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_Theta);
177 /* printf("Pitch matrix\n"); */
178 /* MAT3print(TMP, stdout); */
181 MAT3_SET_VEC(vec, 1.0, 0.0, 0.0);
182 /* MAT3mult_vec(vec, vec, R); */
183 /* MAT3rotate(TMP, vec, FG_Psi - FG_PI_2); */
184 MAT3rotate(TMP, vec, -FG_Psi);
185 /* printf("Yaw matrix\n");
186 MAT3print(TMP, stdout); */
187 MAT3mult(LOCAL, R, TMP);
188 // printf("FG derived LOCAL matrix\n");
189 // MAT3print(LOCAL, stdout);
190 #endif // OLD_LOCAL_TO_BODY_CODE
192 // Derive the local UP transformation matrix based on *geodetic*
194 MAT3_SET_VEC(vec, 0.0, 0.0, 1.0);
195 MAT3rotate(R, vec, FG_Longitude); // R = rotate about Z axis
196 // printf("Longitude matrix\n");
197 // MAT3print(R, stdout);
199 MAT3_SET_VEC(vec, 0.0, 1.0, 0.0);
200 MAT3mult_vec(vec, vec, R);
201 MAT3rotate(TMP, vec, -FG_Latitude); // TMP = rotate about X axis
202 // printf("Latitude matrix\n");
203 // MAT3print(TMP, stdout);
205 MAT3mult(UP, R, TMP);
206 // printf("Local up matrix\n");
207 // MAT3print(UP, stdout);
209 MAT3_SET_VEC(local_up, 1.0, 0.0, 0.0);
210 MAT3mult_vec(local_up, local_up, UP);
212 // printf( "Local Up = (%.4f, %.4f, %.4f)\n",
213 // local_up[0], local_up[1], local_up[2]);
215 // Alternative method to Derive local up vector based on
216 // *geodetic* coordinates
217 // alt_up = fgPolarToCart(FG_Longitude, FG_Latitude, 1.0);
218 // printf( " Alt Up = (%.4f, %.4f, %.4f)\n",
219 // alt_up.x, alt_up.y, alt_up.z);
221 // Calculate the VIEW matrix
222 MAT3mult(VIEW, LOCAL, UP);
223 // printf("VIEW matrix\n");
224 // MAT3print(VIEW, stdout);
226 // generate the current up, forward, and fwrd-view vectors
227 MAT3_SET_VEC(vec, 1.0, 0.0, 0.0);
228 MAT3mult_vec(view_up, vec, VIEW);
230 MAT3_SET_VEC(vec, 0.0, 0.0, 1.0);
231 MAT3mult_vec(forward, vec, VIEW);
232 // printf( "Forward vector is (%.2f,%.2f,%.2f)\n", forward[0], forward[1],
235 MAT3rotate(TMP, view_up, view_offset);
236 MAT3mult_vec(view_forward, forward, TMP);
238 // make a vector to the current view position
239 MAT3_SET_VEC(v0, view_pos.x, view_pos.y, view_pos.z);
241 // Given a vector pointing straight down (-Z), map into onto the
242 // local plane representing "horizontal". This should give us the
243 // local direction for moving "south".
244 MAT3_SET_VEC(minus_z, 0.0, 0.0, -1.0);
245 map_vec_onto_cur_surface_plane(local_up, v0, minus_z, surface_south);
246 MAT3_NORMALIZE_VEC(surface_south, ntmp);
247 // printf( "Surface direction directly south %.2f %.2f %.2f\n",
248 // surface_south[0], surface_south[1], surface_south[2]);
250 // now calculate the surface east vector
251 MAT3rotate(TMP, view_up, FG_PI_2);
252 MAT3mult_vec(surface_east, surface_south, TMP);
253 // printf( "Surface direction directly east %.2f %.2f %.2f\n",
254 // surface_east[0], surface_east[1], surface_east[2]);
255 // printf( "Should be close to zero = %.2f\n",
256 // MAT3_DOT_PRODUCT(surface_south, surface_east));
260 // Update the "World to Eye" transformation matrix
261 // This is most useful for view frustum culling
262 void fgVIEW::UpdateWorldToEye( fgFLIGHT *f ) {
263 MAT3mat R_Phi, R_Theta, R_Psi, R_Lat, R_Lon, T_view;
267 // if we have a view offset use slow way for now
268 if(fabs(view_offset)>FG_EPSILON){
270 MAT3_SET_HVEC(vec, 0.0, 0.0, -1.0, 1.0);
271 MAT3rotate(R_Phi, vec, FG_Phi);
272 // printf("Roll matrix (Phi)\n");
273 // MAT3print(R_Phi, stdout);
276 MAT3_SET_HVEC(vec, 1.0, 0.0, 0.0, 1.0);
277 MAT3rotate(R_Theta, vec, FG_Theta);
278 // printf("\nPitch matrix (Theta)\n");
279 // MAT3print(R_Theta, stdout);
282 MAT3_SET_HVEC(vec, 0.0, -1.0, 0.0, 1.0);
283 MAT3rotate(R_Psi, vec, FG_Psi + FG_PI - view_offset );
284 // printf("\nYaw matrix (Psi)\n");
285 // MAT3print(R_Psi, stdout);
287 // aircraft roll/pitch/yaw
288 MAT3mult(TMP, R_Phi, R_Theta);
289 MAT3mult(AIRCRAFT, TMP, R_Psi);
291 } else { // JUST USE LOCAL_TO_BODY NHV 5/25/98
292 // hey this is even different then LOCAL[][] above ??
294 AIRCRAFT[0][0] = -FG_T_local_to_body_22;
295 AIRCRAFT[0][1] = -FG_T_local_to_body_23;
296 AIRCRAFT[0][2] = FG_T_local_to_body_21;
297 AIRCRAFT[0][3] = 0.0;
298 AIRCRAFT[1][0] = FG_T_local_to_body_32;
299 AIRCRAFT[1][1] = FG_T_local_to_body_33;
300 AIRCRAFT[1][2] = -FG_T_local_to_body_31;
301 AIRCRAFT[1][3] = 0.0;
302 AIRCRAFT[2][0] = FG_T_local_to_body_12;
303 AIRCRAFT[2][1] = FG_T_local_to_body_13;
304 AIRCRAFT[2][2] = -FG_T_local_to_body_11;
305 AIRCRAFT[2][3] = 0.0;
306 AIRCRAFT[3][0] = AIRCRAFT[3][1] = AIRCRAFT[3][2] = AIRCRAFT[3][3] = 0.0;
307 AIRCRAFT[3][3] = 1.0;
309 // ??? SOMETHING LIKE THIS SHOULD WORK NHV
310 // Rotate about LOCAL_UP (AIRCRAFT[2][])
311 // MAT3_SET_HVEC(vec, AIRCRAFT[2][0], AIRCRAFT[2][1],
312 // AIRCRAFT[2][2], AIRCRAFT[2][3]);
313 // MAT3rotate(TMP, vec, FG_PI - view_offset );
314 // MAT3mult(AIRCRAFT, AIRCRAFT, TMP);
316 // printf("\naircraft roll pitch yaw\n");
317 // MAT3print(AIRCRAFT, stdout);
319 // View position in scenery centered coordinates
320 MAT3_SET_HVEC(vec, view_pos.x, view_pos.y, view_pos.z, 1.0);
321 MAT3translate(T_view, vec);
322 // printf("\nTranslation matrix\n");
323 // MAT3print(T_view, stdout);
326 MAT3_SET_HVEC(vec, 1.0, 0.0, 0.0, 1.0);
327 // R_Lat = rotate about X axis
328 MAT3rotate(R_Lat, vec, FG_Latitude);
329 // printf("\nLatitude matrix\n");
330 // MAT3print(R_Lat, stdout);
333 MAT3_SET_HVEC(vec, 0.0, 0.0, 1.0, 1.0);
334 // R_Lon = rotate about Z axis
335 MAT3rotate(R_Lon, vec, FG_Longitude - FG_PI_2 );
336 // printf("\nLongitude matrix\n");
337 // MAT3print(R_Lon, stdout);
339 #ifdef THIS_IS_OLD_CODE
340 // View position in scenery centered coordinates
341 MAT3_SET_HVEC(vec, view_pos.x, view_pos.y, view_pos.z, 1.0);
342 MAT3translate(T_view, vec);
343 // printf("\nTranslation matrix\n");
344 // MAT3print(T_view, stdout);
346 // aircraft roll/pitch/yaw
347 MAT3mult(TMP, R_Phi, R_Theta);
348 MAT3mult(AIRCRAFT, TMP, R_Psi);
349 // printf("\naircraft roll pitch yaw\n");
350 // MAT3print(AIRCRAFT, stdout);
351 #endif THIS_IS_OLD_CODE
354 MAT3mult(WORLD, R_Lat, R_Lon);
355 // printf("\nworld\n");
356 // MAT3print(WORLD, stdout);
358 MAT3mult(EYE_TO_WORLD, AIRCRAFT, WORLD);
359 MAT3mult(EYE_TO_WORLD, EYE_TO_WORLD, T_view);
360 // printf("\nEye to world\n");
361 // MAT3print(EYE_TO_WORLD, stdout);
363 MAT3invert(WORLD_TO_EYE, EYE_TO_WORLD);
364 // printf("\nWorld to eye\n");
365 // MAT3print(WORLD_TO_EYE, stdout);
367 // printf( "\nview_pos = %.2f %.2f %.2f\n",
368 // view_pos.x, view_pos.y, view_pos.z );
370 // MAT3_SET_HVEC(eye, 0.0, 0.0, 0.0, 1.0);
371 // MAT3mult_vec(vec, eye, EYE_TO_WORLD);
372 // printf("\neye -> world = %.2f %.2f %.2f\n", vec[0], vec[1], vec[2]);
374 // MAT3_SET_HVEC(vec1, view_pos.x, view_pos.y, view_pos.z, 1.0);
375 // MAT3mult_vec(vec, vec1, WORLD_TO_EYE);
376 // printf( "\nabs_view_pos -> eye = %.2f %.2f %.2f\n",
377 // vec[0], vec[1], vec[2]);
382 fgVIEW::~fgVIEW( void ) {
386 // Basically, this is a modified version of the Mesa gluLookAt()
387 // function that's been modified slightly so we can capture the result
388 // before sending it off to OpenGL land.
389 void fg_gluLookAt( GLdouble eyex, GLdouble eyey, GLdouble eyez,
390 GLdouble centerx, GLdouble centery, GLdouble centerz,
391 GLdouble upx, GLdouble upy, GLdouble upz )
394 GLdouble x[3], y[3], z[3];
397 m = current_view.MODEL_VIEW;
399 /* Make rotation matrix */
402 z[0] = eyex - centerx;
403 z[1] = eyey - centery;
404 z[2] = eyez - centerz;
405 mag = sqrt( z[0]*z[0] + z[1]*z[1] + z[2]*z[2] );
406 if (mag) { /* mpichler, 19950515 */
417 /* X vector = Y cross Z */
418 x[0] = y[1]*z[2] - y[2]*z[1];
419 x[1] = -y[0]*z[2] + y[2]*z[0];
420 x[2] = y[0]*z[1] - y[1]*z[0];
422 /* Recompute Y = Z cross X */
423 y[0] = z[1]*x[2] - z[2]*x[1];
424 y[1] = -z[0]*x[2] + z[2]*x[0];
425 y[2] = z[0]*x[1] - z[1]*x[0];
427 /* mpichler, 19950515 */
428 /* cross product gives area of parallelogram, which is < 1.0 for
429 * non-perpendicular unit-length vectors; so normalize x, y here
432 mag = sqrt( x[0]*x[0] + x[1]*x[1] + x[2]*x[2] );
439 mag = sqrt( y[0]*y[0] + y[1]*y[1] + y[2]*y[2] );
446 #define M(row,col) m[col*4+row]
447 M(0,0) = x[0]; M(0,1) = x[1]; M(0,2) = x[2]; M(0,3) = 0.0;
448 M(1,0) = y[0]; M(1,1) = y[1]; M(1,2) = y[2]; M(1,3) = 0.0;
449 M(2,0) = z[0]; M(2,1) = z[1]; M(2,2) = z[2]; M(2,3) = 0.0;
450 // the following is part of the original gluLookAt(), but we are
451 // commenting it out because we know we are going to be doing a
452 // translation below which will set these values anyways
453 // M(3,0) = 0.0; M(3,1) = 0.0; M(3,2) = 0.0; M(3,3) = 1.0;
456 // Translate Eye to Origin
457 // replaces: glTranslated( -eyex, -eyey, -eyez );
459 // this has been slightly modified from the original glTranslate()
460 // code because we know that coming into this m[12] = m[13] =
461 // m[14] = 0.0, and m[15] = 1.0;
462 m[12] = m[0] * -eyex + m[4] * -eyey + m[8] * -eyez /* + m[12] */;
463 m[13] = m[1] * -eyex + m[5] * -eyey + m[9] * -eyez /* + m[13] */;
464 m[14] = m[2] * -eyex + m[6] * -eyey + m[10] * -eyez /* + m[14] */;
465 m[15] = 1.0 /* m[3] * -eyex + m[7] * -eyey + m[11] * -eyez + m[15] */;
467 // xglMultMatrixd( m );
473 // Revision 1.17 1998/07/24 21:39:12 curt
474 // Debugging output tweaks.
475 // Cast glGetString to (char *) to avoid compiler errors.
476 // Optimizations to fgGluLookAt() by Norman Vine.
478 // Revision 1.16 1998/07/13 21:01:41 curt
479 // Wrote access functions for current fgOPTIONS.
481 // Revision 1.15 1998/07/12 03:14:43 curt
482 // Added ground collision detection.
483 // Did some serious horsing around to be able to "hug" the ground properly
484 // and still be able to take off.
485 // Set the near clip plane to 1.0 meters when less than 10 meters above the
487 // Did some serious horsing around getting the initial airplane position to be
488 // correct based on rendered terrain elevation.
489 // Added a little cheat/hack that will prevent the view position from ever
490 // dropping below the terrain, even when the flight model doesn't quite
491 // put you as high as you'd like.
493 // Revision 1.14 1998/07/08 14:45:08 curt
494 // polar3d.h renamed to polar3d.hxx
495 // vector.h renamed to vector.hxx
496 // updated audio support so it waits to create audio classes (and tie up
497 // /dev/dsp) until the mpg123 player is finished.
499 // Revision 1.13 1998/07/04 00:52:27 curt
500 // Add my own version of gluLookAt() (which is nearly identical to the
501 // Mesa/glu version.) But, by calculating the Model View matrix our selves
502 // we can save this matrix without having to read it back in from the video
503 // card. This hopefully allows us to save a few cpu cycles when rendering
504 // out the fragments because we can just use glLoadMatrixd() with the
505 // precalculated matrix for each tile rather than doing a push(), translate(),
506 // pop() for every fragment.
508 // Panel status defaults to off for now until it gets a bit more developed.
510 // Extract OpenGL driver info on initialization.
512 // Revision 1.12 1998/06/03 00:47:15 curt
513 // Updated to compile in audio support if OSS available.
514 // Updated for new version of Steve's audio library.
515 // STL includes don't use .h
516 // Small view optimizations.
518 // Revision 1.11 1998/05/27 02:24:05 curt
519 // View optimizations by Norman Vine.
521 // Revision 1.10 1998/05/17 16:59:03 curt
522 // First pass at view frustum culling now operational.
524 // Revision 1.9 1998/05/16 13:08:37 curt
525 // C++ - ified views.[ch]xx
526 // Shuffled some additional view parameters into the fgVIEW class.
527 // Changed tile-radius to tile-diameter because it is a much better
529 // Added a WORLD_TO_EYE transformation to views.cxx. This allows us
530 // to transform world space to eye space for view frustum culling.
532 // Revision 1.8 1998/05/02 01:51:01 curt
533 // Updated polartocart conversion routine.
535 // Revision 1.7 1998/04/30 12:34:20 curt
536 // Added command line rendering options:
537 // enable/disable fog/haze
538 // specify smooth/flat shading
539 // disable sky blending and just use a solid color
540 // enable wireframe drawing mode
542 // Revision 1.6 1998/04/28 01:20:23 curt
543 // Type-ified fgTIME and fgVIEW.
544 // Added a command line option to disable textures.
546 // Revision 1.5 1998/04/26 05:10:04 curt
547 // "struct fgLIGHT" -> "fgLIGHT" because fgLIGHT is typedef'd.
549 // Revision 1.4 1998/04/25 22:04:53 curt
550 // Use already calculated LaRCsim values to create the roll/pitch/yaw
551 // transformation matrix (we call it LOCAL)
553 // Revision 1.3 1998/04/25 20:24:02 curt
554 // Cleaned up initialization sequence to eliminate interdependencies
555 // between sun position, lighting, and view position. This creates a
556 // valid single pass initialization path.
558 // Revision 1.2 1998/04/24 00:49:22 curt
559 // Wrapped "#include <config.h>" in "#ifdef HAVE_CONFIG_H"
560 // Trying out some different option parsing code.
561 // Some code reorganization.
563 // Revision 1.1 1998/04/22 13:25:45 curt
564 // C++ - ifing the code.
565 // Starting a bit of reorganization of lighting code.
567 // Revision 1.16 1998/04/18 04:11:29 curt
568 // Moved fg_debug to it's own library, added zlib support.
570 // Revision 1.15 1998/02/20 00:16:24 curt
571 // Thursday's tweaks.
573 // Revision 1.14 1998/02/09 15:07:50 curt
576 // Revision 1.13 1998/02/07 15:29:45 curt
577 // Incorporated HUD changes and struct/typedef changes from Charlie Hotchkiss
578 // <chotchkiss@namg.us.anritsu.com>
580 // Revision 1.12 1998/01/29 00:50:28 curt
581 // Added a view record field for absolute x, y, z position.
583 // Revision 1.11 1998/01/27 00:47:58 curt
584 // Incorporated Paul Bleisch's <pbleisch@acm.org> new debug message
585 // system and commandline/config file processing code.
587 // Revision 1.10 1998/01/19 19:27:09 curt
588 // Merged in make system changes from Bob Kuehne <rpk@sgi.com>
589 // This should simplify things tremendously.
591 // Revision 1.9 1998/01/13 00:23:09 curt
592 // Initial changes to support loading and management of scenery tiles. Note,
593 // there's still a fair amount of work left to be done.
595 // Revision 1.8 1997/12/30 22:22:33 curt
596 // Further integration of event manager.
598 // Revision 1.7 1997/12/30 20:47:45 curt
599 // Integrated new event manager with subsystem initializations.
601 // Revision 1.6 1997/12/22 04:14:32 curt
602 // Aligned sky with sun so dusk/dawn effects can be correct relative to the sun.
604 // Revision 1.5 1997/12/18 04:07:02 curt
605 // Worked on properly translating and positioning the sky dome.
607 // Revision 1.4 1997/12/17 23:13:36 curt
608 // Began working on rendering a sky.
610 // Revision 1.3 1997/12/15 23:54:50 curt
611 // Add xgl wrappers for debugging.
612 // Generate terrain normals on the fly.
614 // Revision 1.2 1997/12/10 22:37:48 curt
615 // Prepended "fg" on the name of all global structures that didn't have it yet.
616 // i.e. "struct WEATHER {}" became "struct fgWEATHER {}"
618 // Revision 1.1 1997/08/27 21:31:17 curt