1 // sky.cxx -- model sky with an upside down "bowl"
3 // Written by Curtis Olson, started December 1997.
5 // Copyright (C) 1997 Curtis L. Olson - curt@infoplane.com
7 // This program is free software; you can redistribute it and/or
8 // modify it under the terms of the GNU General Public License as
9 // published by the Free Software Foundation; either version 2 of the
10 // License, or (at your option) any later version.
12 // This program is distributed in the hope that it will be useful, but
13 // WITHOUT ANY WARRANTY; without even the implied warranty of
14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 // General Public License for more details.
17 // You should have received a copy of the GNU General Public License
18 // along with this program; if not, write to the Free Software
19 // Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
22 // (Log is kept at end of this file)
38 #include <Aircraft/aircraft.hxx>
39 #include <Debug/fg_debug.h>
40 #include <Flight/flight.hxx>
41 #include <Include/fg_constants.h>
42 #include <Main/views.hxx>
43 #include <Math/fg_random.h>
44 #include <Time/event.hxx>
45 #include <Time/fg_time.hxx>
50 // in meters of course
51 #define CENTER_ELEV 25000.0
53 #define INNER_RADIUS 50000.0
54 #define INNER_ELEV 20000.0
56 #define MIDDLE_RADIUS 70000.0
57 #define MIDDLE_ELEV 8000.0
59 #define OUTER_RADIUS 80000.0
60 #define OUTER_ELEV 0.0
62 #define BOTTOM_RADIUS 50000.0
63 #define BOTTOM_ELEV -2000.0
66 static float inner_vertex[12][3];
67 static float middle_vertex[12][3];
68 static float outer_vertex[12][3];
69 static float bottom_vertex[12][3];
71 static float inner_color[12][4];
72 static float middle_color[12][4];
73 static float outer_color[12][4];
76 // Calculate the sky structure vertices
77 void fgSkyVerticesInit( void ) {
81 fgPrintf(FG_ASTRO, FG_INFO, " Generating the sky dome vertices.\n");
83 for ( i = 0; i < 12; i++ ) {
84 theta = (i * 30.0) * DEG_TO_RAD;
86 inner_vertex[i][0] = cos(theta) * INNER_RADIUS;
87 inner_vertex[i][1] = sin(theta) * INNER_RADIUS;
88 inner_vertex[i][2] = INNER_ELEV;
90 // printf(" %.2f %.2f\n", cos(theta) * INNER_RADIUS,
91 // sin(theta) * INNER_RADIUS);
93 middle_vertex[i][0] = cos((double)theta) * MIDDLE_RADIUS;
94 middle_vertex[i][1] = sin((double)theta) * MIDDLE_RADIUS;
95 middle_vertex[i][2] = MIDDLE_ELEV;
97 outer_vertex[i][0] = cos((double)theta) * OUTER_RADIUS;
98 outer_vertex[i][1] = sin((double)theta) * OUTER_RADIUS;
99 outer_vertex[i][2] = OUTER_ELEV;
101 bottom_vertex[i][0] = cos((double)theta) * BOTTOM_RADIUS;
102 bottom_vertex[i][1] = sin((double)theta) * BOTTOM_RADIUS;
103 bottom_vertex[i][2] = BOTTOM_ELEV;
108 // (Re)calculate the sky colors at each vertex
109 void fgSkyColorsInit( void ) {
111 double sun_angle, diff;
112 double outer_param[3], outer_amt[3], outer_diff[3];
113 double middle_param[3], middle_amt[3], middle_diff[3];
116 l = &cur_light_params;
118 fgPrintf( FG_ASTRO, FG_INFO,
119 " Generating the sky colors for each vertex.\n" );
121 // setup for the possibility of sunset effects
122 sun_angle = l->sun_angle * RAD_TO_DEG;
123 // fgPrintf( FG_ASTRO, FG_INFO,
124 // " Sun angle in degrees = %.2f\n", sun_angle);
126 if ( (sun_angle > 80.0) && (sun_angle < 100.0) ) {
128 outer_param[0] = (10.0 - fabs(90.0 - sun_angle)) / 20.0;
129 outer_param[1] = (10.0 - fabs(90.0 - sun_angle)) / 40.0;
130 outer_param[2] = -(10.0 - fabs(90.0 - sun_angle)) / 30.0;
131 // outer_param[2] = 0.0;
133 middle_param[0] = (10.0 - fabs(90.0 - sun_angle)) / 40.0;
134 middle_param[1] = (10.0 - fabs(90.0 - sun_angle)) / 80.0;
135 middle_param[2] = 0.0;
137 outer_diff[0] = outer_param[0] / 6.0;
138 outer_diff[1] = outer_param[1] / 6.0;
139 outer_diff[2] = outer_param[2] / 6.0;
141 middle_diff[0] = middle_param[0] / 6.0;
142 middle_diff[1] = middle_param[1] / 6.0;
143 middle_diff[2] = middle_param[2] / 6.0;
145 outer_param[0] = outer_param[1] = outer_param[2] = 0.0;
146 middle_param[0] = middle_param[1] = middle_param[2] = 0.0;
148 outer_diff[0] = outer_diff[1] = outer_diff[2] = 0.0;
149 middle_diff[0] = middle_diff[1] = middle_diff[2] = 0.0;
151 // printf(" outer_red_param = %.2f outer_red_diff = %.2f\n",
152 // outer_red_param, outer_red_diff);
154 // calculate transition colors between sky and fog
155 for ( j = 0; j < 3; j++ ) {
156 outer_amt[j] = outer_param[j];
157 middle_amt[j] = middle_param[j];
160 for ( i = 0; i < 6; i++ ) {
161 for ( j = 0; j < 3; j++ ) {
162 diff = l->sky_color[j] - l->fog_color[j];
164 // printf("sky = %.2f fog = %.2f diff = %.2f\n",
165 // l->sky_color[j], l->fog_color[j], diff);
167 inner_color[i][j] = l->sky_color[j] - diff * 0.3;
168 middle_color[i][j] = l->sky_color[j] - diff * 0.9 + middle_amt[j];
169 outer_color[i][j] = l->fog_color[j] + outer_amt[j];
171 if ( inner_color[i][j] > 1.00 ) { inner_color[i][j] = 1.00; }
172 if ( inner_color[i][j] < 0.10 ) { inner_color[i][j] = 0.10; }
173 if ( middle_color[i][j] > 1.00 ) { middle_color[i][j] = 1.00; }
174 if ( middle_color[i][j] < 0.10 ) { middle_color[i][j] = 0.10; }
175 if ( outer_color[i][j] > 1.00 ) { outer_color[i][j] = 1.00; }
176 if ( outer_color[i][j] < 0.10 ) { outer_color[i][j] = 0.10; }
178 inner_color[i][3] = middle_color[i][3] = outer_color[i][3] =
181 for ( j = 0; j < 3; j++ ) {
182 outer_amt[j] -= outer_diff[j];
183 middle_amt[j] -= middle_diff[j];
187 printf("inner_color[%d] = %.2f %.2f %.2f %.2f\n", i, inner_color[i][0],
188 inner_color[i][1], inner_color[i][2], inner_color[i][3]);
189 printf("middle_color[%d] = %.2f %.2f %.2f %.2f\n", i,
190 middle_color[i][0], middle_color[i][1], middle_color[i][2],
192 printf("outer_color[%d] = %.2f %.2f %.2f %.2f\n", i,
193 outer_color[i][0], outer_color[i][1], outer_color[i][2],
198 for ( j = 0; j < 3; j++ ) {
203 for ( i = 6; i < 12; i++ ) {
205 for ( j = 0; j < 3; j++ ) {
206 diff = l->sky_color[j] - l->fog_color[j];
208 // printf("sky = %.2f fog = %.2f diff = %.2f\n",
209 // l->sky_color[j], l->fog_color[j], diff);
211 inner_color[i][j] = l->sky_color[j] - diff * 0.3;
212 middle_color[i][j] = l->sky_color[j] - diff * 0.9 + middle_amt[j];
213 outer_color[i][j] = l->fog_color[j] + outer_amt[j];
215 if ( inner_color[i][j] > 1.00 ) { inner_color[i][j] = 1.00; }
216 if ( inner_color[i][j] < 0.10 ) { inner_color[i][j] = 0.10; }
217 if ( middle_color[i][j] > 1.00 ) { middle_color[i][j] = 1.00; }
218 if ( middle_color[i][j] < 0.10 ) { middle_color[i][j] = 0.10; }
219 if ( outer_color[i][j] > 1.00 ) { outer_color[i][j] = 1.00; }
220 if ( outer_color[i][j] < 0.15 ) { outer_color[i][j] = 0.15; }
222 inner_color[i][3] = middle_color[i][3] = outer_color[i][3] =
225 for ( j = 0; j < 3; j++ ) {
226 outer_amt[j] += outer_diff[j];
227 middle_amt[j] += middle_diff[j];
231 printf("inner_color[%d] = %.2f %.2f %.2f %.2f\n", i, inner_color[i][0],
232 inner_color[i][1], inner_color[i][2], inner_color[i][3]);
233 printf("middle_color[%d] = %.2f %.2f %.2f %.2f\n", i,
234 middle_color[i][0], middle_color[i][1], middle_color[i][2],
236 printf("outer_color[%d] = %.2f %.2f %.2f %.2f\n", i,
237 outer_color[i][0], outer_color[i][1], outer_color[i][2],
244 // Initialize the sky structure and colors
245 void fgSkyInit( void ) {
246 fgPrintf(FG_ASTRO, FG_INFO, "Initializing the sky\n");
250 // regester fgSkyColorsInit() as an event to be run periodically
251 global_events.Register( "fgSkyColorsInit()", fgSkyColorsInit,
252 fgEVENT::FG_EVENT_READY, 30000);
257 void fgSkyRender( void ) {
261 float inner_color[4];
262 float middle_color[4];
263 float outer_color[4];
267 f = current_aircraft.flight;
268 l = &cur_light_params;
271 // printf("Rendering the sky.\n");
273 // calculate the proper colors
274 for ( i = 0; i < 3; i++ ) {
275 diff = l->sky_color[i] - l->adj_fog_color[i];
277 // printf("sky = %.2f fog = %.2f diff = %.2f\n",
278 // l->sky_color[j], l->adj_fog_color[j], diff);
280 inner_color[i] = l->sky_color[i] - diff * 0.3;
281 middle_color[i] = l->sky_color[i] - diff * 0.9;
282 outer_color[i] = l->adj_fog_color[i];
284 inner_color[3] = middle_color[3] = outer_color[3] = l->adj_fog_color[3];
288 // Translate to view position
289 xglTranslatef( v->cur_zero_elev.x(),
290 v->cur_zero_elev.y(),
291 v->cur_zero_elev.z() );
292 // printf(" Translated to %.2f %.2f %.2f\n",
293 // v->cur_zero_elev.x, v->cur_zero_elev.y, v->cur_zero_elev.z );
295 // Rotate to proper orientation
296 // printf(" lon = %.2f lat = %.2f\n", FG_Longitude * RAD_TO_DEG,
297 // FG_Latitude * RAD_TO_DEG);
298 xglRotatef( FG_Longitude * RAD_TO_DEG, 0.0, 0.0, 1.0 );
299 xglRotatef( 90.0 - FG_Latitude * RAD_TO_DEG, 0.0, 1.0, 0.0 );
300 xglRotatef( l->sun_rotation * RAD_TO_DEG, 0.0, 0.0, 1.0 );
302 // Draw inner/center section of sky*/
303 xglBegin( GL_TRIANGLE_FAN );
304 xglColor4fv(l->sky_color);
305 xglVertex3f(0.0, 0.0, CENTER_ELEV);
306 for ( i = 0; i < 12; i++ ) {
307 xglColor4fv( inner_color );
308 xglVertex3fv( inner_vertex[i] );
310 xglColor4fv( inner_color );
311 xglVertex3fv( inner_vertex[0] );
314 // Draw the middle ring
315 xglBegin( GL_TRIANGLE_STRIP );
316 for ( i = 0; i < 12; i++ ) {
317 xglColor4fv( middle_color );
318 // printf("middle_color[%d] = %.2f %.2f %.2f %.2f\n", i,
319 // middle_color[i][0], middle_color[i][1], middle_color[i][2],
320 // middle_color[i][3]);
321 // xglColor4f(1.0, 0.0, 0.0, 1.0);
322 xglVertex3fv( middle_vertex[i] );
323 xglColor4fv( inner_color );
324 // printf("inner_color[%d] = %.2f %.2f %.2f %.2f\n", i,
325 // inner_color[i][0], inner_color[i][1], inner_color[i][2],
326 // inner_color[i][3]);
327 // xglColor4f(0.0, 0.0, 1.0, 1.0);
328 xglVertex3fv( inner_vertex[i] );
330 xglColor4fv( middle_color );
331 // xglColor4f(1.0, 0.0, 0.0, 1.0);
332 xglVertex3fv( middle_vertex[0] );
333 xglColor4fv( inner_color );
334 // xglColor4f(0.0, 0.0, 1.0, 1.0);
335 xglVertex3fv( inner_vertex[0] );
338 // Draw the outer ring
339 xglBegin( GL_TRIANGLE_STRIP );
340 for ( i = 0; i < 12; i++ ) {
341 xglColor4fv( outer_color );
342 xglVertex3fv( outer_vertex[i] );
343 xglColor4fv( middle_color );
344 xglVertex3fv( middle_vertex[i] );
346 xglColor4fv( outer_color );
347 xglVertex3fv( outer_vertex[0] );
348 xglColor4fv( middle_color );
349 xglVertex3fv( middle_vertex[0] );
352 // Draw the bottom skirt
353 xglBegin( GL_TRIANGLE_STRIP );
354 xglColor4fv( outer_color );
355 for ( i = 0; i < 12; i++ ) {
356 xglVertex3fv( bottom_vertex[i] );
357 xglVertex3fv( outer_vertex[i] );
359 xglVertex3fv( bottom_vertex[0] );
360 xglVertex3fv( outer_vertex[0] );
368 // Revision 1.13 1998/10/20 18:28:30 curt
369 // Tweaked sunset/sunrise colors.
371 // Revision 1.12 1998/10/16 23:27:18 curt
374 // Revision 1.11 1998/10/16 00:52:19 curt
375 // Converted to Point3D class.
377 // Revision 1.10 1998/08/29 13:07:16 curt
378 // Rewrite of event manager thanks to Bernie Bright.
380 // Revision 1.9 1998/08/22 01:18:59 curt
381 // Minor tweaks to avoid using unitialized memory.
383 // Revision 1.8 1998/08/12 21:40:44 curt
384 // Sky now tracks adjusted fog color so it blends well with terrain.
386 // Revision 1.7 1998/07/22 21:39:21 curt
387 // Lower skirt tracks adjusted fog color, not fog color.
389 // Revision 1.6 1998/05/23 14:07:14 curt
390 // Use new C++ events class.
392 // Revision 1.5 1998/04/28 01:19:02 curt
393 // Type-ified fgTIME and fgVIEW
395 // Revision 1.4 1998/04/26 05:10:01 curt
396 // "struct fgLIGHT" -> "fgLIGHT" because fgLIGHT is typedef'd.
398 // Revision 1.3 1998/04/25 22:06:25 curt
399 // Edited cvs log messages in source files ... bad bad bad!
401 // Revision 1.2 1998/04/24 00:45:03 curt
402 // Wrapped "#include <config.h>" in "#ifdef HAVE_CONFIG_H"
403 // Fixed a bug when generating sky colors.
405 // Revision 1.1 1998/04/22 13:21:32 curt
406 // C++ - ifing the code a bit.
408 // Revision 1.9 1998/04/03 21:52:50 curt
409 // Converting to Gnu autoconf system.
411 // Revision 1.8 1998/03/09 22:47:25 curt
412 // Incorporated Durk's updates.
414 // Revision 1.7 1998/02/19 13:05:49 curt
415 // Incorporated some HUD tweaks from Michelle America.
416 // Tweaked the sky's sunset/rise colors.
417 // Other misc. tweaks.
419 // Revision 1.6 1998/02/07 15:29:32 curt
420 // Incorporated HUD changes and struct/typedef changes from Charlie Hotchkiss
421 // <chotchkiss@namg.us.anritsu.com>
423 // Revision 1.5 1998/01/27 00:47:48 curt
424 // Incorporated Paul Bleisch's <pbleisch@acm.org> new debug message
425 // system and commandline/config file processing code.
427 // Revision 1.4 1998/01/26 15:54:28 curt
428 // Added a "skirt" to try to help hide gaps between scenery and sky. This will
429 // have to be revisited in the future.
431 // Revision 1.3 1998/01/19 19:26:59 curt
432 // Merged in make system changes from Bob Kuehne <rpk@sgi.com>
433 // This should simplify things tremendously.
435 // Revision 1.2 1998/01/19 18:40:17 curt
436 // Tons of little changes to clean up the code and to remove fatal errors
437 // when building with the c++ compiler.
439 // Revision 1.1 1998/01/07 03:16:19 curt
440 // Moved from .../Src/Scenery/ to .../Src/Astro/
442 // Revision 1.11 1997/12/30 22:22:38 curt
443 // Further integration of event manager.
445 // Revision 1.10 1997/12/30 20:47:53 curt
446 // Integrated new event manager with subsystem initializations.
448 // Revision 1.9 1997/12/30 13:06:57 curt
449 // A couple lighting tweaks ...
451 // Revision 1.8 1997/12/23 04:58:38 curt
452 // Tweaked the sky coloring a bit to build in structures to allow finer rgb
455 // Revision 1.7 1997/12/22 23:45:48 curt
456 // First stab at sunset/sunrise sky glow effects.
458 // Revision 1.6 1997/12/22 04:14:34 curt
459 // Aligned sky with sun so dusk/dawn effects can be correct relative to the sun.
461 // Revision 1.5 1997/12/19 23:34:59 curt
462 // Lot's of tweaking with sky rendering and lighting.
464 // Revision 1.4 1997/12/19 16:45:02 curt
465 // Working on scene rendering order and options.
467 // Revision 1.3 1997/12/18 23:32:36 curt
468 // First stab at sky dome actually starting to look reasonable. :-)
470 // Revision 1.2 1997/12/18 04:07:03 curt
471 // Worked on properly translating and positioning the sky dome.
473 // Revision 1.1 1997/12/17 23:14:30 curt
475 // Begin work on rendering the sky. (Rather than just using a clear screen.)