1 // dome.cxx -- model sky with an upside down "bowl"
3 // Written by Curtis Olson, started December 1997.
4 // SSG-ified by Curtis Olson, February 2000.
6 // Copyright (C) 1997-2000 Curtis L. Olson - http://www.flightgear.org/~curt
8 // This library is free software; you can redistribute it and/or
9 // modify it under the terms of the GNU Library General Public
10 // License as published by the Free Software Foundation; either
11 // version 2 of the License, or (at your option) any later version.
13 // This library is distributed in the hope that it will be useful,
14 // but WITHOUT ANY WARRANTY; without even the implied warranty of
15 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 // Library General Public License for more details.
18 // You should have received a copy of the GNU Library General Public
19 // License along with this library; if not, write to the
20 // Free Software Foundation, Inc., 59 Temple Place - Suite 330,
21 // Boston, MA 02111-1307, USA.
27 # include <simgear_config.h>
36 #include <simgear/compiler.h>
42 #include <simgear/debug/logstream.hxx>
48 # pragma global_optimizer off
52 // proportions of max dimensions fed to the build() routine
53 static const float center_elev = 1.0;
55 static const float upper_radius = 0.6;
56 static const float upper_elev = 0.15;
58 static const float middle_radius = 0.9;
59 static const float middle_elev = 0.08;
61 static const float lower_radius = 1.0;
62 static const float lower_elev = 0.0;
64 static const float bottom_radius = 0.8;
65 static const float bottom_elev = -0.1;
68 // Set up dome rendering callbacks
69 static int sgSkyDomePreDraw( ssgEntity *e ) {
70 /* cout << endl << "Dome Pre Draw" << endl << "----------------"
73 ssgLeaf *f = (ssgLeaf *)e;
74 if ( f -> hasState () ) f->getState()->apply() ;
76 glPushAttrib( GL_DEPTH_BUFFER_BIT | GL_FOG_BIT );
77 // cout << "push error = " << glGetError() << endl;
79 glDisable( GL_DEPTH_TEST );
85 static int sgSkyDomePostDraw( ssgEntity *e ) {
86 /* cout << endl << "Dome Post Draw" << endl << "----------------"
90 // cout << "pop error = " << glGetError() << endl;
97 SGSkyDome::SGSkyDome( void ) {
103 SGSkyDome::~SGSkyDome( void ) {
107 // initialize the sky object and connect it into our scene graph
108 ssgBranch * SGSkyDome::build( double hscale, double vscale ) {
115 dome_state = new ssgSimpleState();
116 dome_state->setShadeModel( GL_SMOOTH );
117 dome_state->disable( GL_LIGHTING );
118 dome_state->disable( GL_CULL_FACE );
119 dome_state->disable( GL_TEXTURE_2D );
120 dome_state->enable( GL_COLOR_MATERIAL );
121 dome_state->setColourMaterial( GL_AMBIENT_AND_DIFFUSE );
122 dome_state->setMaterial( GL_EMISSION, 0, 0, 0, 1 );
123 dome_state->setMaterial( GL_SPECULAR, 0, 0, 0, 1 );
124 dome_state->disable( GL_BLEND );
125 dome_state->disable( GL_ALPHA_TEST );
128 center_disk_vl = new ssgVertexArray( 14 );
129 center_disk_cl = new ssgColourArray( 14 );
131 upper_ring_vl = new ssgVertexArray( 26 );
132 upper_ring_cl = new ssgColourArray( 26 );
134 middle_ring_vl = new ssgVertexArray( 26 );
135 middle_ring_cl = new ssgColourArray( 26 );
137 lower_ring_vl = new ssgVertexArray( 26 );
138 lower_ring_cl = new ssgColourArray( 26 );
140 // initially seed to all blue
141 sgSetVec4( color, 0.0, 0.0, 1.0, 1.0 );
143 // generate the raw vertex data
144 sgVec3 center_vertex;
145 sgVec3 upper_vertex[12];
146 sgVec3 middle_vertex[12];
147 sgVec3 lower_vertex[12];
148 sgVec3 bottom_vertex[12];
150 sgSetVec3( center_vertex, 0.0, 0.0, center_elev * vscale );
152 for ( i = 0; i < 12; i++ ) {
153 theta = (i * 30.0) * SGD_DEGREES_TO_RADIANS;
155 sgSetVec3( upper_vertex[i],
156 cos(theta) * upper_radius * hscale,
157 sin(theta) * upper_radius * hscale,
158 upper_elev * vscale );
160 sgSetVec3( middle_vertex[i],
161 cos(theta) * middle_radius * hscale,
162 sin(theta) * middle_radius * hscale,
163 middle_elev * vscale );
165 sgSetVec3( lower_vertex[i],
166 cos(theta) * lower_radius * hscale,
167 sin(theta) * lower_radius * hscale,
168 lower_elev * vscale );
170 sgSetVec3( bottom_vertex[i],
171 cos(theta) * bottom_radius * hscale,
172 sin(theta) * bottom_radius * hscale,
173 bottom_elev * vscale );
176 // generate the center disk vertex/color arrays
177 center_disk_vl->add( center_vertex );
178 center_disk_cl->add( color );
179 for ( i = 11; i >= 0; i-- ) {
180 center_disk_vl->add( upper_vertex[i] );
181 center_disk_cl->add( color );
183 center_disk_vl->add( upper_vertex[11] );
184 center_disk_cl->add( color );
186 // generate the upper ring
187 for ( i = 0; i < 12; i++ ) {
188 upper_ring_vl->add( middle_vertex[i] );
189 upper_ring_cl->add( color );
191 upper_ring_vl->add( upper_vertex[i] );
192 upper_ring_cl->add( color );
194 upper_ring_vl->add( middle_vertex[0] );
195 upper_ring_cl->add( color );
197 upper_ring_vl->add( upper_vertex[0] );
198 upper_ring_cl->add( color );
200 // generate middle ring
201 for ( i = 0; i < 12; i++ ) {
202 middle_ring_vl->add( lower_vertex[i] );
203 middle_ring_cl->add( color );
205 middle_ring_vl->add( middle_vertex[i] );
206 middle_ring_cl->add( color );
208 middle_ring_vl->add( lower_vertex[0] );
209 middle_ring_cl->add( color );
211 middle_ring_vl->add( middle_vertex[0] );
212 middle_ring_cl->add( color );
214 // generate lower ring
215 for ( i = 0; i < 12; i++ ) {
216 lower_ring_vl->add( bottom_vertex[i] );
217 lower_ring_cl->add( color );
219 lower_ring_vl->add( lower_vertex[i] );
220 lower_ring_cl->add( color );
222 lower_ring_vl->add( bottom_vertex[0] );
223 lower_ring_cl->add( color );
225 lower_ring_vl->add( lower_vertex[0] );
226 lower_ring_cl->add( color );
228 // force a repaint of the sky colors with ugly defaults
230 sgSetVec4( fog_color, 1.0, 1.0, 1.0, 1.0 );
231 repaint( color, fog_color, 0.0, 5000.0 );
233 // build the ssg scene graph sub tree for the sky and connected
234 // into the provide scene graph branch
235 ssgVtxTable *center_disk, *upper_ring, *middle_ring, *lower_ring;
237 center_disk = new ssgVtxTable( GL_TRIANGLE_FAN,
238 center_disk_vl, NULL, NULL, center_disk_cl );
240 upper_ring = new ssgVtxTable( GL_TRIANGLE_STRIP,
241 upper_ring_vl, NULL, NULL, upper_ring_cl );
243 middle_ring = new ssgVtxTable( GL_TRIANGLE_STRIP,
244 middle_ring_vl, NULL, NULL, middle_ring_cl );
246 lower_ring = new ssgVtxTable( GL_TRIANGLE_STRIP,
247 lower_ring_vl, NULL, NULL, lower_ring_cl );
249 center_disk->setState( dome_state );
250 upper_ring->setState( dome_state );
251 middle_ring->setState( dome_state );
252 lower_ring->setState( dome_state );
254 dome_transform = new ssgTransform;
255 dome_transform->addKid( center_disk );
256 dome_transform->addKid( upper_ring );
257 dome_transform->addKid( middle_ring );
258 dome_transform->addKid( lower_ring );
260 // not entirely satisfying. We are depending here that the first
261 // thing we add to a parent is the first drawn
262 center_disk->setCallback( SSG_CALLBACK_PREDRAW, sgSkyDomePreDraw );
263 center_disk->setCallback( SSG_CALLBACK_POSTDRAW, sgSkyDomePostDraw );
265 upper_ring->setCallback( SSG_CALLBACK_PREDRAW, sgSkyDomePreDraw );
266 upper_ring->setCallback( SSG_CALLBACK_POSTDRAW, sgSkyDomePostDraw );
268 middle_ring->setCallback( SSG_CALLBACK_PREDRAW, sgSkyDomePreDraw );
269 middle_ring->setCallback( SSG_CALLBACK_POSTDRAW, sgSkyDomePostDraw );
271 lower_ring->setCallback( SSG_CALLBACK_PREDRAW, sgSkyDomePreDraw );
272 lower_ring->setCallback( SSG_CALLBACK_POSTDRAW, sgSkyDomePostDraw );
274 return dome_transform;
277 static void fade_to_black( sgVec4 sky_color[], float asl, int count) {
278 const float ref_asl = 10000.0f;
279 const sgVec3 space_color = {0.0f, 0.0f, 0.0f};
280 float d = exp( - asl / ref_asl );
281 for(int i = 0; i < count ; i++)
282 sgLerpVec3( sky_color[i], sky_color[i], space_color, 1.0 - d);
285 // repaint the sky colors based on current value of sun_angle, sky,
286 // and fog colors. This updates the color arrays for ssgVtxTable.
287 // sun angle in degrees relative to verticle
288 // 0 degrees = high noon
289 // 90 degrees = sun rise/set
290 // 180 degrees = darkest midnight
291 bool SGSkyDome::repaint( sgVec4 sky_color, sgVec4 fog_color, double sun_angle,
294 double diff, prev_sun_angle = 999.0;
295 sgVec3 outer_param, outer_amt, outer_diff;
296 sgVec3 middle_param, middle_amt, middle_diff;
299 if (prev_sun_angle == sun_angle)
302 prev_sun_angle = sun_angle;
304 // Check for sunrise/sunset condition
305 if (sun_angle > 80.0) // && (sun_angle < 100.0) )
308 sgSetVec3( outer_param,
309 (10.0 - fabs(90.0 - sun_angle)) / 20.0,
310 (10.0 - fabs(90.0 - sun_angle)) / 40.0,
311 -(10.0 - fabs(90.0 - sun_angle)) / 30.0 );
313 sgSetVec3( middle_param,
314 (10.0 - fabs(90.0 - sun_angle)) / 40.0,
315 (10.0 - fabs(90.0 - sun_angle)) / 80.0,
318 sgScaleVec3( outer_diff, outer_param, 1.0 / 6.0 );
320 sgScaleVec3( middle_diff, middle_param, 1.0 / 6.0 );
322 sgSetVec3( outer_param, 0.0, 0.0, 0.0 );
323 sgSetVec3( middle_param, 0.0, 0.0, 0.0 );
325 sgSetVec3( outer_diff, 0.0, 0.0, 0.0 );
326 sgSetVec3( middle_diff, 0.0, 0.0, 0.0 );
328 // printf(" outer_red_param = %.2f outer_red_diff = %.2f\n",
329 // outer_red_param, outer_red_diff);
331 // calculate transition colors between sky and fog
332 sgCopyVec3( outer_amt, outer_param );
333 sgCopyVec3( middle_amt, middle_param );
336 // First, recalulate the basic colors
340 sgVec4 upper_color[12];
341 sgVec4 middle_color[12];
342 sgVec4 lower_color[12];
343 sgVec4 bottom_color[12];
345 double vis_factor, cvf = vis;
350 vis_factor = (vis - 1000.0) / 2000.0;
351 if ( vis_factor < 0.0 ) {
353 } else if ( vis_factor > 1.0) {
357 for ( j = 0; j < 3; j++ ) {
358 diff = sky_color[j] - fog_color[j];
359 center_color[j] = sky_color[j]; // - diff * ( 1.0 - vis_factor );
361 center_color[3] = 1.0;
363 for ( i = 0; i < 6; i++ ) {
364 for ( j = 0; j < 3; j++ ) {
365 double saif = sun_angle/SG_PI;
366 diff = (sky_color[j] - fog_color[j]) * (0.8 + j * 0.2) * (0.8 + saif - ((6-i)/10));
368 // printf("sky = %.2f fog = %.2f diff = %.2f\n",
369 // l->sky_color[j], l->fog_color[j], diff);
371 upper_color[i][j] = sky_color[j] - diff *
372 ( 1.0 - vis_factor * (0.7 + 0.3 * cvf/45000) );
373 middle_color[i][j] = sky_color[j] - diff *
374 ( 1.0 - vis_factor * (0.1 + 0.85 * cvf/45000) )
376 lower_color[i][j] = fog_color[j] + outer_amt[j];
378 if ( upper_color[i][j] > 1.0 ) { upper_color[i][j] = 1.0; }
379 if ( upper_color[i][j] < 0.0 ) { upper_color[i][j] = 0.0; }
380 if ( middle_color[i][j] > 1.0 ) { middle_color[i][j] = 1.0; }
381 if ( middle_color[i][j] < 0.0 ) { middle_color[i][j] = 0.0; }
382 if ( lower_color[i][j] > 1.0 ) { lower_color[i][j] = 1.0; }
383 if ( lower_color[i][j] < 0.0 ) { lower_color[i][j] = 0.0; }
385 upper_color[i][3] = middle_color[i][3] = lower_color[i][3] = 1.0;
387 for ( j = 0; j < 3; j++ ) {
388 outer_amt[j] -= outer_diff[j];
389 middle_amt[j] -= middle_diff[j];
393 printf("upper_color[%d] = %.2f %.2f %.2f %.2f\n", i, upper_color[i][0],
394 upper_color[i][1], upper_color[i][2], upper_color[i][3]);
395 printf("middle_color[%d] = %.2f %.2f %.2f %.2f\n", i,
396 middle_color[i][0], middle_color[i][1], middle_color[i][2],
398 printf("lower_color[%d] = %.2f %.2f %.2f %.2f\n", i,
399 lower_color[i][0], lower_color[i][1], lower_color[i][2],
404 sgSetVec3( outer_amt, 0.0, 0.0, 0.0 );
405 sgSetVec3( middle_amt, 0.0, 0.0, 0.0 );
407 for ( i = 6; i < 12; i++ ) {
408 for ( j = 0; j < 3; j++ ) {
409 double saif = sun_angle/SG_PI;
410 diff = (sky_color[j] - fog_color[j]) * (0.8 + j * 0.2) * (0.8 + saif - ((-i+12)/10));
412 // printf("sky = %.2f fog = %.2f diff = %.2f\n",
413 // sky_color[j], fog_color[j], diff);
415 upper_color[i][j] = sky_color[j] - diff *
416 ( 1.0 - vis_factor * (0.7 + 0.3 * cvf/45000) );
417 middle_color[i][j] = sky_color[j] - diff *
418 ( 1.0 - vis_factor * (0.1 + 0.85 * cvf/45000) )
420 lower_color[i][j] = fog_color[j] + outer_amt[j];
422 if ( upper_color[i][j] > 1.0 ) { upper_color[i][j] = 1.0; }
423 if ( upper_color[i][j] < 0.0 ) { upper_color[i][j] = 0.0; }
424 if ( middle_color[i][j] > 1.0 ) { middle_color[i][j] = 1.0; }
425 if ( middle_color[i][j] < 0.0 ) { middle_color[i][j] = 0.0; }
426 if ( lower_color[i][j] > 1.0 ) { lower_color[i][j] = 1.0; }
427 if ( lower_color[i][j] < 0.0 ) { lower_color[i][j] = 0.0; }
429 upper_color[i][3] = middle_color[i][3] = lower_color[i][3] = 1.0;
431 for ( j = 0; j < 3; j++ ) {
432 outer_amt[j] += outer_diff[j];
433 middle_amt[j] += middle_diff[j];
437 printf("upper_color[%d] = %.2f %.2f %.2f %.2f\n", i, upper_color[i][0],
438 upper_color[i][1], upper_color[i][2], upper_color[i][3]);
439 printf("middle_color[%d] = %.2f %.2f %.2f %.2f\n", i,
440 middle_color[i][0], middle_color[i][1], middle_color[i][2],
442 printf("lower_color[%d] = %.2f %.2f %.2f %.2f\n", i,
443 lower_color[i][0], lower_color[i][1], lower_color[i][2],
448 fade_to_black( (sgVec4 *) center_color, asl * center_elev, 1);
449 fade_to_black( upper_color, (asl+0.05f) * upper_elev, 12);
450 fade_to_black( middle_color, (asl+0.05f) * middle_elev, 12);
451 fade_to_black( lower_color, (asl+0.05f) * lower_elev, 12);
453 for ( i = 0; i < 12; i++ ) {
454 sgCopyVec4( bottom_color[i], fog_color );
458 // Second, assign the basic colors to the object color arrays
464 // update the center disk color arrays
466 slot = center_disk_cl->get( counter++ );
468 // sgSetVec4( red, 1.0, 0.0, 0.0, 1.0 );
469 sgCopyVec4( slot, center_color );
470 for ( i = 11; i >= 0; i-- ) {
471 slot = center_disk_cl->get( counter++ );
472 sgCopyVec4( slot, upper_color[i] );
474 slot = center_disk_cl->get( counter++ );
475 sgCopyVec4( slot, upper_color[11] );
477 // generate the upper ring
479 for ( i = 0; i < 12; i++ ) {
480 slot = upper_ring_cl->get( counter++ );
481 sgCopyVec4( slot, middle_color[i] );
483 slot = upper_ring_cl->get( counter++ );
484 sgCopyVec4( slot, upper_color[i] );
486 slot = upper_ring_cl->get( counter++ );
487 sgCopyVec4( slot, middle_color[0] );
489 slot = upper_ring_cl->get( counter++ );
490 sgCopyVec4( slot, upper_color[0] );
492 // generate middle ring
494 for ( i = 0; i < 12; i++ ) {
495 slot = middle_ring_cl->get( counter++ );
496 sgCopyVec4( slot, lower_color[i] );
498 slot = middle_ring_cl->get( counter++ );
499 sgCopyVec4( slot, middle_color[i] );
501 slot = middle_ring_cl->get( counter++ );
502 sgCopyVec4( slot, lower_color[0] );
504 slot = middle_ring_cl->get( counter++ );
505 sgCopyVec4( slot, middle_color[0] );
507 // generate lower ring
509 for ( i = 0; i < 12; i++ ) {
510 slot = lower_ring_cl->get( counter++ );
511 sgCopyVec4( slot, bottom_color[i] );
513 slot = lower_ring_cl->get( counter++ );
514 sgCopyVec4( slot, lower_color[i] );
516 slot = lower_ring_cl->get( counter++ );
517 sgCopyVec4( slot, bottom_color[0] );
519 slot = lower_ring_cl->get( counter++ );
520 sgCopyVec4( slot, lower_color[0] );
526 // reposition the sky at the specified origin and orientation
527 // lon specifies a rotation about the Z axis
528 // lat specifies a rotation about the new Y axis
529 // spin specifies a rotation about the new Z axis (and orients the
530 // sunrise/set effects
531 bool SGSkyDome::reposition( sgVec3 p, double lon, double lat, double spin ) {
532 sgMat4 T, LON, LAT, SPIN;
535 // Translate to view position
536 // Point3D zero_elev = current_view.get_cur_zero_elev();
537 // xglTranslatef( zero_elev.x(), zero_elev.y(), zero_elev.z() );
538 sgMakeTransMat4( T, p );
540 // printf(" Translated to %.2f %.2f %.2f\n",
541 // zero_elev.x, zero_elev.y, zero_elev.z );
543 // Rotate to proper orientation
544 // printf(" lon = %.2f lat = %.2f\n",
545 // lon * SGD_RADIANS_TO_DEGREES,
546 // lat * SGD_RADIANS_TO_DEGREES);
547 // xglRotatef( lon * SGD_RADIANS_TO_DEGREES, 0.0, 0.0, 1.0 );
548 sgSetVec3( axis, 0.0, 0.0, 1.0 );
549 sgMakeRotMat4( LON, lon * SGD_RADIANS_TO_DEGREES, axis );
551 // xglRotatef( 90.0 - f->get_Latitude() * SGD_RADIANS_TO_DEGREES,
553 sgSetVec3( axis, 0.0, 1.0, 0.0 );
554 sgMakeRotMat4( LAT, 90.0 - lat * SGD_RADIANS_TO_DEGREES, axis );
556 // xglRotatef( l->sun_rotation * SGD_RADIANS_TO_DEGREES, 0.0, 0.0, 1.0 );
557 sgSetVec3( axis, 0.0, 0.0, 1.0 );
558 sgMakeRotMat4( SPIN, spin * SGD_RADIANS_TO_DEGREES, axis );
562 sgCopyMat4( TRANSFORM, T );
563 sgPreMultMat4( TRANSFORM, LON );
564 sgPreMultMat4( TRANSFORM, LAT );
565 sgPreMultMat4( TRANSFORM, SPIN );
568 sgSetCoord( &skypos, TRANSFORM );
570 dome_transform->setTransform( &skypos );
571 asl = - skypos.xyz[2];