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 General Public License
19 // along with this program; if not, write to the Free Software
20 // Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
26 # include <simgear_config.h>
35 #include <simgear/compiler.h>
41 #include <simgear/debug/logstream.hxx>
47 # pragma global_optimizer off
51 // proportions of max dimensions fed to the build() routine
52 static const float center_elev = 1.0;
54 static const float upper_radius = 0.6;
55 static const float upper_elev = 0.15;
57 static const float middle_radius = 0.9;
58 static const float middle_elev = 0.08;
60 static const float lower_radius = 1.0;
61 static const float lower_elev = 0.0;
63 static const float bottom_radius = 0.8;
64 static const float bottom_elev = -0.1;
67 // Set up dome rendering callbacks
68 static int sgSkyDomePreDraw( ssgEntity *e ) {
69 /* cout << endl << "Dome Pre Draw" << endl << "----------------"
72 ssgLeaf *f = (ssgLeaf *)e;
73 if ( f -> hasState () ) f->getState()->apply() ;
75 glPushAttrib( GL_DEPTH_BUFFER_BIT | GL_FOG_BIT );
76 // cout << "push error = " << glGetError() << endl;
78 glDisable( GL_DEPTH_TEST );
84 static int sgSkyDomePostDraw( ssgEntity *e ) {
85 /* cout << endl << "Dome Post Draw" << endl << "----------------"
89 // cout << "pop error = " << glGetError() << endl;
96 SGSkyDome::SGSkyDome( void ) {
102 SGSkyDome::~SGSkyDome( void ) {
106 // initialize the sky object and connect it into our scene graph
107 ssgBranch * SGSkyDome::build( double hscale, double vscale ) {
114 dome_state = new ssgSimpleState();
115 dome_state->setShadeModel( GL_SMOOTH );
116 dome_state->disable( GL_LIGHTING );
117 dome_state->disable( GL_CULL_FACE );
118 dome_state->disable( GL_TEXTURE_2D );
119 dome_state->enable( GL_COLOR_MATERIAL );
120 dome_state->setColourMaterial( GL_AMBIENT_AND_DIFFUSE );
121 dome_state->setMaterial( GL_EMISSION, 0, 0, 0, 1 );
122 dome_state->setMaterial( GL_SPECULAR, 0, 0, 0, 1 );
123 dome_state->disable( GL_BLEND );
124 dome_state->disable( GL_ALPHA_TEST );
127 center_disk_vl = new ssgVertexArray( 14 );
128 center_disk_cl = new ssgColourArray( 14 );
130 upper_ring_vl = new ssgVertexArray( 26 );
131 upper_ring_cl = new ssgColourArray( 26 );
133 middle_ring_vl = new ssgVertexArray( 26 );
134 middle_ring_cl = new ssgColourArray( 26 );
136 lower_ring_vl = new ssgVertexArray( 26 );
137 lower_ring_cl = new ssgColourArray( 26 );
139 // initially seed to all blue
140 sgSetVec4( color, 0.0, 0.0, 1.0, 1.0 );
142 // generate the raw vertex data
143 sgVec3 center_vertex;
144 sgVec3 upper_vertex[12];
145 sgVec3 middle_vertex[12];
146 sgVec3 lower_vertex[12];
147 sgVec3 bottom_vertex[12];
149 sgSetVec3( center_vertex, 0.0, 0.0, center_elev * vscale );
151 for ( i = 0; i < 12; i++ ) {
152 theta = (i * 30.0) * SGD_DEGREES_TO_RADIANS;
154 sgSetVec3( upper_vertex[i],
155 cos(theta) * upper_radius * hscale,
156 sin(theta) * upper_radius * hscale,
157 upper_elev * vscale );
159 sgSetVec3( middle_vertex[i],
160 cos(theta) * middle_radius * hscale,
161 sin(theta) * middle_radius * hscale,
162 middle_elev * vscale );
164 sgSetVec3( lower_vertex[i],
165 cos(theta) * lower_radius * hscale,
166 sin(theta) * lower_radius * hscale,
167 lower_elev * vscale );
169 sgSetVec3( bottom_vertex[i],
170 cos(theta) * bottom_radius * hscale,
171 sin(theta) * bottom_radius * hscale,
172 bottom_elev * vscale );
175 // generate the center disk vertex/color arrays
176 center_disk_vl->add( center_vertex );
177 center_disk_cl->add( color );
178 for ( i = 11; i >= 0; i-- ) {
179 center_disk_vl->add( upper_vertex[i] );
180 center_disk_cl->add( color );
182 center_disk_vl->add( upper_vertex[11] );
183 center_disk_cl->add( color );
185 // generate the upper ring
186 for ( i = 0; i < 12; i++ ) {
187 upper_ring_vl->add( middle_vertex[i] );
188 upper_ring_cl->add( color );
190 upper_ring_vl->add( upper_vertex[i] );
191 upper_ring_cl->add( color );
193 upper_ring_vl->add( middle_vertex[0] );
194 upper_ring_cl->add( color );
196 upper_ring_vl->add( upper_vertex[0] );
197 upper_ring_cl->add( color );
199 // generate middle ring
200 for ( i = 0; i < 12; i++ ) {
201 middle_ring_vl->add( lower_vertex[i] );
202 middle_ring_cl->add( color );
204 middle_ring_vl->add( middle_vertex[i] );
205 middle_ring_cl->add( color );
207 middle_ring_vl->add( lower_vertex[0] );
208 middle_ring_cl->add( color );
210 middle_ring_vl->add( middle_vertex[0] );
211 middle_ring_cl->add( color );
213 // generate lower ring
214 for ( i = 0; i < 12; i++ ) {
215 lower_ring_vl->add( bottom_vertex[i] );
216 lower_ring_cl->add( color );
218 lower_ring_vl->add( lower_vertex[i] );
219 lower_ring_cl->add( color );
221 lower_ring_vl->add( bottom_vertex[0] );
222 lower_ring_cl->add( color );
224 lower_ring_vl->add( lower_vertex[0] );
225 lower_ring_cl->add( color );
227 // force a repaint of the sky colors with ugly defaults
229 sgSetVec4( fog_color, 1.0, 1.0, 1.0, 1.0 );
230 repaint( color, fog_color, 0.0, 5000.0 );
232 // build the ssg scene graph sub tree for the sky and connected
233 // into the provide scene graph branch
234 ssgVtxTable *center_disk, *upper_ring, *middle_ring, *lower_ring;
236 center_disk = new ssgVtxTable( GL_TRIANGLE_FAN,
237 center_disk_vl, NULL, NULL, center_disk_cl );
239 upper_ring = new ssgVtxTable( GL_TRIANGLE_STRIP,
240 upper_ring_vl, NULL, NULL, upper_ring_cl );
242 middle_ring = new ssgVtxTable( GL_TRIANGLE_STRIP,
243 middle_ring_vl, NULL, NULL, middle_ring_cl );
245 lower_ring = new ssgVtxTable( GL_TRIANGLE_STRIP,
246 lower_ring_vl, NULL, NULL, lower_ring_cl );
248 center_disk->setState( dome_state );
249 upper_ring->setState( dome_state );
250 middle_ring->setState( dome_state );
251 lower_ring->setState( dome_state );
253 dome_transform = new ssgTransform;
254 dome_transform->addKid( center_disk );
255 dome_transform->addKid( upper_ring );
256 dome_transform->addKid( middle_ring );
257 dome_transform->addKid( lower_ring );
259 // not entirely satisfying. We are depending here that the first
260 // thing we add to a parent is the first drawn
261 center_disk->setCallback( SSG_CALLBACK_PREDRAW, sgSkyDomePreDraw );
262 center_disk->setCallback( SSG_CALLBACK_POSTDRAW, sgSkyDomePostDraw );
264 upper_ring->setCallback( SSG_CALLBACK_PREDRAW, sgSkyDomePreDraw );
265 upper_ring->setCallback( SSG_CALLBACK_POSTDRAW, sgSkyDomePostDraw );
267 middle_ring->setCallback( SSG_CALLBACK_PREDRAW, sgSkyDomePreDraw );
268 middle_ring->setCallback( SSG_CALLBACK_POSTDRAW, sgSkyDomePostDraw );
270 lower_ring->setCallback( SSG_CALLBACK_PREDRAW, sgSkyDomePreDraw );
271 lower_ring->setCallback( SSG_CALLBACK_POSTDRAW, sgSkyDomePostDraw );
273 return dome_transform;
276 static void fade_to_black( sgVec4 sky_color[], float asl, int count) {
277 const float ref_asl = 10000.0f;
278 const sgVec3 space_color = {0.0f, 0.0f, 0.0f};
279 float d = exp( - asl / ref_asl );
280 for(int i = 0; i < count ; i++)
281 sgLerpVec3( sky_color[i], sky_color[i], space_color, 1.0 - d);
284 // repaint the sky colors based on current value of sun_angle, sky,
285 // and fog colors. This updates the color arrays for ssgVtxTable.
286 // sun angle in degrees relative to verticle
287 // 0 degrees = high noon
288 // 90 degrees = sun rise/set
289 // 180 degrees = darkest midnight
290 bool SGSkyDome::repaint( sgVec4 sky_color, sgVec4 fog_color, double sun_angle,
293 double diff, prev_sun_angle = 999.0;
294 sgVec3 outer_param, outer_amt, outer_diff;
295 sgVec3 middle_param, middle_amt, middle_diff;
298 if (prev_sun_angle == sun_angle)
301 prev_sun_angle = sun_angle;
303 // Check for sunrise/sunset condition
304 if (sun_angle > 80.0) // && (sun_angle < 100.0) )
307 sgSetVec3( outer_param,
308 (10.0 - fabs(90.0 - sun_angle)) / 20.0,
309 (10.0 - fabs(90.0 - sun_angle)) / 40.0,
310 -(10.0 - fabs(90.0 - sun_angle)) / 30.0 );
312 sgSetVec3( middle_param,
313 (10.0 - fabs(90.0 - sun_angle)) / 40.0,
314 (10.0 - fabs(90.0 - sun_angle)) / 80.0,
317 sgScaleVec3( outer_diff, outer_param, 1.0 / 6.0 );
319 sgScaleVec3( middle_diff, middle_param, 1.0 / 6.0 );
321 sgSetVec3( outer_param, 0.0, 0.0, 0.0 );
322 sgSetVec3( middle_param, 0.0, 0.0, 0.0 );
324 sgSetVec3( outer_diff, 0.0, 0.0, 0.0 );
325 sgSetVec3( middle_diff, 0.0, 0.0, 0.0 );
327 // printf(" outer_red_param = %.2f outer_red_diff = %.2f\n",
328 // outer_red_param, outer_red_diff);
330 // calculate transition colors between sky and fog
331 sgCopyVec3( outer_amt, outer_param );
332 sgCopyVec3( middle_amt, middle_param );
335 // First, recalulate the basic colors
339 sgVec4 upper_color[12];
340 sgVec4 middle_color[12];
341 sgVec4 lower_color[12];
342 sgVec4 bottom_color[12];
344 double vis_factor, cvf = vis;
349 vis_factor = (vis - 1000.0) / 2000.0;
350 if ( vis_factor < 0.0 ) {
352 } else if ( vis_factor > 1.0) {
356 for ( j = 0; j < 3; j++ ) {
357 diff = sky_color[j] - fog_color[j];
358 center_color[j] = sky_color[j]; // - diff * ( 1.0 - vis_factor );
360 center_color[3] = 1.0;
362 for ( i = 0; i < 6; i++ ) {
363 for ( j = 0; j < 3; j++ ) {
364 double saif = sun_angle/SG_PI;
365 diff = (sky_color[j] - fog_color[j]) * (0.8 + j * 0.2) * (0.8 + saif - ((6-i)/10));
367 // printf("sky = %.2f fog = %.2f diff = %.2f\n",
368 // l->sky_color[j], l->fog_color[j], diff);
370 upper_color[i][j] = sky_color[j] - diff *
371 ( 1.0 - vis_factor * (0.7 + 0.3 * cvf/45000) );
372 middle_color[i][j] = sky_color[j] - diff *
373 ( 1.0 - vis_factor * (0.1 + 0.85 * cvf/45000) )
375 lower_color[i][j] = fog_color[j] + outer_amt[j];
377 if ( upper_color[i][j] > 1.0 ) { upper_color[i][j] = 1.0; }
378 if ( upper_color[i][j] < 0.0 ) { upper_color[i][j] = 0.0; }
379 if ( middle_color[i][j] > 1.0 ) { middle_color[i][j] = 1.0; }
380 if ( middle_color[i][j] < 0.0 ) { middle_color[i][j] = 0.0; }
381 if ( lower_color[i][j] > 1.0 ) { lower_color[i][j] = 1.0; }
382 if ( lower_color[i][j] < 0.0 ) { lower_color[i][j] = 0.0; }
384 upper_color[i][3] = middle_color[i][3] = lower_color[i][3] = 1.0;
386 for ( j = 0; j < 3; j++ ) {
387 outer_amt[j] -= outer_diff[j];
388 middle_amt[j] -= middle_diff[j];
392 printf("upper_color[%d] = %.2f %.2f %.2f %.2f\n", i, upper_color[i][0],
393 upper_color[i][1], upper_color[i][2], upper_color[i][3]);
394 printf("middle_color[%d] = %.2f %.2f %.2f %.2f\n", i,
395 middle_color[i][0], middle_color[i][1], middle_color[i][2],
397 printf("lower_color[%d] = %.2f %.2f %.2f %.2f\n", i,
398 lower_color[i][0], lower_color[i][1], lower_color[i][2],
403 sgSetVec3( outer_amt, 0.0, 0.0, 0.0 );
404 sgSetVec3( middle_amt, 0.0, 0.0, 0.0 );
406 for ( i = 6; i < 12; i++ ) {
407 for ( j = 0; j < 3; j++ ) {
408 double saif = sun_angle/SG_PI;
409 diff = (sky_color[j] - fog_color[j]) * (0.8 + j * 0.2) * (0.8 + saif - ((-i+12)/10));
411 // printf("sky = %.2f fog = %.2f diff = %.2f\n",
412 // sky_color[j], fog_color[j], diff);
414 upper_color[i][j] = sky_color[j] - diff *
415 ( 1.0 - vis_factor * (0.7 + 0.3 * cvf/45000) );
416 middle_color[i][j] = sky_color[j] - diff *
417 ( 1.0 - vis_factor * (0.1 + 0.85 * cvf/45000) )
419 lower_color[i][j] = fog_color[j] + outer_amt[j];
421 if ( upper_color[i][j] > 1.0 ) { upper_color[i][j] = 1.0; }
422 if ( upper_color[i][j] < 0.0 ) { upper_color[i][j] = 0.0; }
423 if ( middle_color[i][j] > 1.0 ) { middle_color[i][j] = 1.0; }
424 if ( middle_color[i][j] < 0.0 ) { middle_color[i][j] = 0.0; }
425 if ( lower_color[i][j] > 1.0 ) { lower_color[i][j] = 1.0; }
426 if ( lower_color[i][j] < 0.0 ) { lower_color[i][j] = 0.0; }
428 upper_color[i][3] = middle_color[i][3] = lower_color[i][3] = 1.0;
430 for ( j = 0; j < 3; j++ ) {
431 outer_amt[j] += outer_diff[j];
432 middle_amt[j] += middle_diff[j];
436 printf("upper_color[%d] = %.2f %.2f %.2f %.2f\n", i, upper_color[i][0],
437 upper_color[i][1], upper_color[i][2], upper_color[i][3]);
438 printf("middle_color[%d] = %.2f %.2f %.2f %.2f\n", i,
439 middle_color[i][0], middle_color[i][1], middle_color[i][2],
441 printf("lower_color[%d] = %.2f %.2f %.2f %.2f\n", i,
442 lower_color[i][0], lower_color[i][1], lower_color[i][2],
447 fade_to_black( (sgVec4 *) center_color, asl * center_elev, 1);
448 fade_to_black( upper_color, (asl+0.05f) * upper_elev, 12);
449 fade_to_black( middle_color, (asl+0.05f) * middle_elev, 12);
450 fade_to_black( lower_color, (asl+0.05f) * lower_elev, 12);
452 for ( i = 0; i < 12; i++ ) {
453 sgCopyVec4( bottom_color[i], fog_color );
457 // Second, assign the basic colors to the object color arrays
463 // update the center disk color arrays
465 slot = center_disk_cl->get( counter++ );
467 // sgSetVec4( red, 1.0, 0.0, 0.0, 1.0 );
468 sgCopyVec4( slot, center_color );
469 for ( i = 11; i >= 0; i-- ) {
470 slot = center_disk_cl->get( counter++ );
471 sgCopyVec4( slot, upper_color[i] );
473 slot = center_disk_cl->get( counter++ );
474 sgCopyVec4( slot, upper_color[11] );
476 // generate the upper ring
478 for ( i = 0; i < 12; i++ ) {
479 slot = upper_ring_cl->get( counter++ );
480 sgCopyVec4( slot, middle_color[i] );
482 slot = upper_ring_cl->get( counter++ );
483 sgCopyVec4( slot, upper_color[i] );
485 slot = upper_ring_cl->get( counter++ );
486 sgCopyVec4( slot, middle_color[0] );
488 slot = upper_ring_cl->get( counter++ );
489 sgCopyVec4( slot, upper_color[0] );
491 // generate middle ring
493 for ( i = 0; i < 12; i++ ) {
494 slot = middle_ring_cl->get( counter++ );
495 sgCopyVec4( slot, lower_color[i] );
497 slot = middle_ring_cl->get( counter++ );
498 sgCopyVec4( slot, middle_color[i] );
500 slot = middle_ring_cl->get( counter++ );
501 sgCopyVec4( slot, lower_color[0] );
503 slot = middle_ring_cl->get( counter++ );
504 sgCopyVec4( slot, middle_color[0] );
506 // generate lower ring
508 for ( i = 0; i < 12; i++ ) {
509 slot = lower_ring_cl->get( counter++ );
510 sgCopyVec4( slot, bottom_color[i] );
512 slot = lower_ring_cl->get( counter++ );
513 sgCopyVec4( slot, lower_color[i] );
515 slot = lower_ring_cl->get( counter++ );
516 sgCopyVec4( slot, bottom_color[0] );
518 slot = lower_ring_cl->get( counter++ );
519 sgCopyVec4( slot, lower_color[0] );
525 // reposition the sky at the specified origin and orientation
526 // lon specifies a rotation about the Z axis
527 // lat specifies a rotation about the new Y axis
528 // spin specifies a rotation about the new Z axis (and orients the
529 // sunrise/set effects
530 bool SGSkyDome::reposition( sgVec3 p, double lon, double lat, double spin ) {
531 sgMat4 T, LON, LAT, SPIN;
534 // Translate to view position
535 // Point3D zero_elev = current_view.get_cur_zero_elev();
536 // xglTranslatef( zero_elev.x(), zero_elev.y(), zero_elev.z() );
537 sgMakeTransMat4( T, p );
539 // printf(" Translated to %.2f %.2f %.2f\n",
540 // zero_elev.x, zero_elev.y, zero_elev.z );
542 // Rotate to proper orientation
543 // printf(" lon = %.2f lat = %.2f\n",
544 // lon * SGD_RADIANS_TO_DEGREES,
545 // lat * SGD_RADIANS_TO_DEGREES);
546 // xglRotatef( lon * SGD_RADIANS_TO_DEGREES, 0.0, 0.0, 1.0 );
547 sgSetVec3( axis, 0.0, 0.0, 1.0 );
548 sgMakeRotMat4( LON, lon * SGD_RADIANS_TO_DEGREES, axis );
550 // xglRotatef( 90.0 - f->get_Latitude() * SGD_RADIANS_TO_DEGREES,
552 sgSetVec3( axis, 0.0, 1.0, 0.0 );
553 sgMakeRotMat4( LAT, 90.0 - lat * SGD_RADIANS_TO_DEGREES, axis );
555 // xglRotatef( l->sun_rotation * SGD_RADIANS_TO_DEGREES, 0.0, 0.0, 1.0 );
556 sgSetVec3( axis, 0.0, 0.0, 1.0 );
557 sgMakeRotMat4( SPIN, spin * SGD_RADIANS_TO_DEGREES, axis );
561 sgCopyMat4( TRANSFORM, T );
562 sgPreMultMat4( TRANSFORM, LON );
563 sgPreMultMat4( TRANSFORM, LAT );
564 sgPreMultMat4( TRANSFORM, SPIN );
567 sgSetCoord( &skypos, TRANSFORM );
569 dome_transform->setTransform( &skypos );
570 asl = - skypos.xyz[2];