1 // sky.cxx -- ssg based sky model
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.
25 # include <simgear_config.h>
29 #include "cloudfield.hxx"
30 #include "newcloud.hxx"
32 #include <simgear/math/sg_random.h>
33 #include <simgear/scene/util/RenderConstants.hxx>
35 #include <osg/StateSet>
39 SGSky::SGSky( void ) {
40 effective_visibility = visibility = 10000.0;
42 // near cloud visibility state variables
51 clouds_3d_enabled = false;
52 clouds_3d_density = 0.8;
54 pre_root = new osg::Group;
55 pre_root->setNodeMask(simgear::BACKGROUND_BIT);
56 osg::StateSet* preStateSet = new osg::StateSet;
57 preStateSet->setAttribute(new osg::Depth(osg::Depth::LESS, 0.0, 1.0,
59 pre_root->setStateSet(preStateSet);
60 cloud_root = new osg::Group;
61 cloud_root->setNodeMask(simgear::MODEL_BIT);
63 pre_selector = new osg::Switch;
65 pre_transform = new osg::Group;
67 _ephTransform = new osg::MatrixTransform;
77 // initialize the sky and connect the components to the scene graph at
78 // the provided branch
79 void SGSky::build( double h_radius_m, double v_radius_m,
80 double sun_size, double moon_size,
81 const SGEphemeris& eph, SGPropertyNode *property_tree_node )
84 pre_transform->addChild( dome->build( h_radius_m, v_radius_m ) );
86 pre_transform->addChild(_ephTransform.get());
87 planets = new SGStars;
88 _ephTransform->addChild( planets->build(eph.getNumPlanets(), eph.getPlanets(), h_radius_m) );
91 _ephTransform->addChild( stars->build(eph.getNumStars(), eph.getStars(), h_radius_m) );
94 _ephTransform->addChild( moon->build(tex_path, moon_size) );
97 _ephTransform->addChild( oursun->build(tex_path, sun_size, property_tree_node ) );
99 pre_selector->addChild( pre_transform.get() );
101 pre_root->addChild( pre_selector.get() );
105 // repaint the sky components based on current value of sun_angle,
106 // sky, and fog colors.
108 // sun angle in degrees relative to verticle
109 // 0 degrees = high noon
110 // 90 degrees = sun rise/set
111 // 180 degrees = darkest midnight
112 bool SGSky::repaint( const SGSkyColor &sc, const SGEphemeris& eph )
114 if ( effective_visibility > 1000.0 ) {
116 dome->repaint( sc.adj_sky_color, sc.sky_color, sc.fog_color,
117 sc.sun_angle, effective_visibility );
119 stars->repaint( sc.sun_angle, eph.getNumStars(), eph.getStars() );
120 planets->repaint( sc.sun_angle, eph.getNumPlanets(), eph.getPlanets() );
121 oursun->repaint( sc.sun_angle, effective_visibility );
122 moon->repaint( sc.moon_angle );
124 for ( unsigned i = 0; i < cloud_layers.size(); ++i ) {
125 if (cloud_layers[i]->getCoverage() != SGCloudLayer::SG_CLOUD_CLEAR){
126 cloud_layers[i]->repaint( sc.cloud_color );
133 SGCloudField::updateFog((double)effective_visibility,
134 osg::Vec4f(toOsg(sc.fog_color), 1.0f));
138 // reposition the sky at the specified origin and orientation
140 // lon specifies a rotation about the Z axis
141 // lat specifies a rotation about the new Y axis
142 // spin specifies a rotation about the new Z axis (this allows
143 // additional orientation for the sunrise/set effects and is used by
144 // the skydome and perhaps clouds.
145 bool SGSky::reposition( const SGSkyState &st, const SGEphemeris& eph, double dt )
147 double angle = st.gst * 15; // degrees
148 double angleRad = SGMiscd::deg2rad(angle);
150 SGVec3f zero_elev, view_up;
151 double lon, lat, alt;
153 SGGeod geodZeroViewPos = SGGeod::fromGeodM(st.pos_geod, 0);
154 zero_elev = toVec3f( SGVec3d::fromGeod(geodZeroViewPos) );
155 view_up = toVec3f( st.ori.backTransform(SGVec3d::e2()) );
156 lon = st.pos_geod.getLongitudeRad();
157 lat = st.pos_geod.getLatitudeRad();
158 alt = st.pos_geod.getElevationM();
160 dome->reposition( zero_elev, alt, lon, lat, st.spin );
162 osg::Matrix m = osg::Matrix::rotate(angleRad, osg::Vec3(0, 0, -1));
163 m.postMultTranslate(toOsg(st.pos));
164 _ephTransform->setMatrix(m);
166 double sun_ra = eph.getSunRightAscension();
167 double sun_dec = eph.getSunDeclination();
168 oursun->reposition( sun_ra, sun_dec, st.sun_dist, lat, alt, st.sun_angle );
170 double moon_ra = eph.getMoonRightAscension();
171 double moon_dec = eph.getMoonDeclination();
172 moon->reposition( moon_ra, moon_dec, st.moon_dist );
174 for ( unsigned i = 0; i < cloud_layers.size(); ++i ) {
175 if ( cloud_layers[i]->getCoverage() != SGCloudLayer::SG_CLOUD_CLEAR ) {
176 cloud_layers[i]->reposition( zero_elev, view_up, lon, lat, alt, dt);
178 cloud_layers[i]->getNode()->setAllChildrenOff();
185 SGSky::add_cloud_layer( SGCloudLayer * layer )
187 cloud_layers.push_back(layer);
188 cloud_root->addChild(layer->getNode());
190 layer->set_enable3dClouds(clouds_3d_enabled);
194 SGSky::get_cloud_layer (int i) const
196 return cloud_layers[i];
200 SGSky::get_cloud_layer (int i)
202 return cloud_layers[i];
206 SGSky::get_cloud_layer_count () const
208 return cloud_layers.size();
211 double SGSky::get_3dCloudDensity() const {
212 return SGNewCloud::getDensity();
215 void SGSky::set_3dCloudDensity(double density)
217 SGNewCloud::setDensity(density);
220 float SGSky::get_3dCloudVisRange() const {
221 return SGCloudField::getVisRange();
224 void SGSky::set_3dCloudVisRange(float vis)
226 SGCloudField::setVisRange(vis);
227 for ( int i = 0; i < (int)cloud_layers.size(); ++i ) {
228 cloud_layers[i]->get_layer3D()->applyVisRange();
232 void SGSky::texture_path( const string& path ) {
233 tex_path = SGPath( path );
236 // modify the current visibility based on cloud layers, thickness,
237 // transition range, and simulated "puffs".
238 void SGSky::modify_vis( float alt, float time_factor ) {
239 float effvis = visibility;
241 for ( int i = 0; i < (int)cloud_layers.size(); ++i ) {
242 float asl = cloud_layers[i]->getElevation_m();
243 float thickness = cloud_layers[i]->getThickness_m();
244 float transition = cloud_layers[i]->getTransition_m();
248 if ( cloud_layers[i]->getCoverage() == SGCloudLayer::SG_CLOUD_CLEAR ) {
249 // less than 50% coverage -- assume we're in the clear for now
251 } else if ( alt < asl - transition ) {
254 } else if ( alt < asl ) {
255 // in lower transition
256 ratio = (asl - alt) / transition;
257 } else if ( alt < asl + thickness ) {
260 } else if ( alt < asl + thickness + transition ) {
261 // in upper transition
262 ratio = (alt - (asl + thickness)) / transition;
268 if ( cloud_layers[i]->getCoverage() == SGCloudLayer::SG_CLOUD_CLEAR ||
269 cloud_layers[i]->get_layer3D()->defined3D) {
270 // do nothing, clear layers aren't drawn, don't affect
271 // visibility andn dont' need to be faded in or out.
272 } else if ( (cloud_layers[i]->getCoverage() ==
273 SGCloudLayer::SG_CLOUD_FEW)
274 || (cloud_layers[i]->getCoverage() ==
275 SGCloudLayer::SG_CLOUD_SCATTERED) )
277 // set the alpha fade value for the cloud layer. For less
278 // dense cloud layers we fade the layer to nothing as we
279 // approach it because we stay clear visibility-wise as we
281 float temp = ratio * 2.0;
282 if ( temp > 1.0 ) { temp = 1.0; }
283 cloud_layers[i]->setAlpha( temp );
285 // don't touch visibility
287 // maintain full alpha for denser cloud layer types.
288 // Let's set the value explicitly in case someone changed
290 cloud_layers[i]->setAlpha( 1.0 );
292 // lower visibility as we approach the cloud layer.
293 // accumulate effects from multiple cloud layers
300 // calc chance of entering cloud puff
301 double rnd = sg_random();
302 double chance = rnd * rnd * rnd;
303 if ( chance > 0.95 /* * (diff - 25) / 50.0 */ ) {
305 puff_length = sg_random() * 2.0; // up to 2 seconds
306 puff_progression = 0.0;
311 // modify actual_visibility based on puff envelope
313 if ( puff_progression <= ramp_up ) {
314 double x = SGD_PI_2 * puff_progression / ramp_up;
315 double factor = 1.0 - sin( x );
316 // cout << "ramp up = " << puff_progression
317 // << " factor = " << factor << endl;
318 effvis = effvis * factor;
319 } else if ( puff_progression >= ramp_up + puff_length ) {
320 double x = SGD_PI_2 *
321 (puff_progression - (ramp_up + puff_length)) /
323 double factor = sin( x );
324 // cout << "ramp down = "
325 // << puff_progression - (ramp_up + puff_length)
326 // << " factor = " << factor << endl;
327 effvis = effvis * factor;
332 /* cout << "len = " << puff_length
334 << " factor = " << factor
335 << " actual_visibility = " << actual_visibility
338 // time_factor = ( global_multi_loop *
339 // current_options.get_speed_up() ) /
340 // (double)current_options.get_model_hz();
342 puff_progression += time_factor;
343 // cout << "time factor = " << time_factor << endl;
345 /* cout << "gml = " << global_multi_loop
346 << " speed up = " << current_options.get_speed_up()
347 << " hz = " << current_options.get_model_hz() << endl;
350 if ( puff_progression > puff_length + ramp_up + ramp_down) {
357 // never let visibility drop below 25 meters
358 if ( effvis <= 25.0 ) {
364 effective_visibility = effvis;