src/Environment/fgclouds.cxx

   1 // Build a cloud layer based on metar
   2 //
   3 // Written by Harald JOHNSEN, started April 2005.
   4 //
   5 // Copyright (C) 2005  Harald JOHNSEN - hjohnsen@evc.net
   6 //
   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.
  11 //
  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.
  16 //
  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, 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA
  20 //
  21 //
  22
  23 #include <Main/fg_props.hxx>
  24
  25 #include <simgear/constants.h>
  26 #include <simgear/sound/soundmgr_openal.hxx>
  27 #include <simgear/scene/sky/sky.hxx>
  28 #include <simgear/environment/visual_enviro.hxx>
  29 #include <simgear/scene/sky/cloudfield.hxx>
  30 #include <simgear/scene/sky/newcloud.hxx>
  31 #include <simgear/math/sg_random.h>
  32 #include <Main/globals.hxx>
  33 #include <Airports/simple.hxx>
  34 #include <Main/util.hxx>
  35
  36 #include "environment_ctrl.hxx"
  37 #include "environment_mgr.hxx"
  38 #include "fgmetar.hxx"
  39 #include "fgclouds.hxx"
  40
  41 extern SGSky *thesky;
  42
  43
  44 FGClouds::FGClouds(FGEnvironmentCtrl * controller) :
  45         station_elevation_ft(0.0),
  46         _controller( controller ),
  47         snd_lightning(NULL),
  48     last_scenario( "none" ),
  49     last_env_config( new SGPropertyNode() ),
  50     last_env_clouds( new SGPropertyNode() )
  51 {
  52         update_event = 0;
  53         fgSetString("/environment/weather-scenario", last_scenario.c_str());
  54 }
  55 FGClouds::~FGClouds() {
  56 }
  57
  58 int FGClouds::get_update_event(void) const {
  59         return update_event;
  60 }
  61 void FGClouds::set_update_event(int count) {
  62         update_event = count;
  63         build();
  64 }
  65
  66 void FGClouds::init(void) {
  67         if( snd_lightning == NULL ) {
  68                 snd_lightning = new SGSoundSample(globals->get_fg_root().c_str(), "Sounds/thunder.wav", true);
  69                 snd_lightning->set_max_dist(7000.0f);
  70                 snd_lightning->set_reference_dist(3000.0f);
  71                 SGSoundMgr *soundMgr = globals->get_soundmgr();
  72                 soundMgr->add( snd_lightning, "thunder" );
  73                 sgEnviro.set_soundMgr( soundMgr );
  74         }
  75 }
  76
  77 SGNewCloud *FGClouds::buildCloud(SGPropertyNode *cloud_def_root, const string& name) {
  78         SGPropertyNode *cld_def=NULL;
  79
  80         cld_def = cloud_def_root->getChild(name.c_str());
  81         string base_name = name.substr(0,2);
  82         if( !cld_def ) {
  83                 if( name[2] == '-' ) {
  84                         cld_def = cloud_def_root->getChild(base_name.c_str());
  85                 }
  86                 if( !cld_def )
  87                         return NULL;
  88         }
  89         string familly = cld_def->getStringValue("familly", base_name.c_str());
  90         SGNewCloud *cld = new SGNewCloud(familly);
  91         for(int i = 0; i < cld_def->nChildren() ; i++) {
  92                 SGPropertyNode *abox = cld_def->getChild(i);
  93                 if( strcmp(abox->getName(), "box") == 0) {
  94                         double x = abox->getDoubleValue("x");
  95                         double y = abox->getDoubleValue("y");
  96                         double z = abox->getDoubleValue("z");
  97                         double size = abox->getDoubleValue("size");
  98                         int type = abox->getIntValue("type", SGNewCloud::CLbox_standard);
  99                         cld->addContainer(x, y, z, size, (SGNewCloud::CLbox_type) type);
 100                 }
 101         }
 102         cld->genSprites();
 103         return cld;
 104 }
 105
 106 void FGClouds::buildLayer(SGCloudField *layer, const string& name, double alt, double coverage) {
 107         struct {
 108                 string name;
 109                 double count;
 110         } tCloudVariety[20];
 111         int CloudVarietyCount = 0;
 112         double totalCount = 0.0;
 113
 114         SGPropertyNode *cloud_def_root = fgGetNode("/environment/cloudlayers/clouds", false);
 115         SGPropertyNode *layer_def_root = fgGetNode("/environment/cloudlayers/layers", false);
 116
 117         layer->clear();
 118         // when we don't generate clouds the layer is rendered in 2D
 119         if( coverage == 0.0 )
 120                 return;
 121         if( layer_def_root == NULL || cloud_def_root == NULL)
 122                 return;
 123         if( name == "ci" || name == "sc" || name == "st")
 124                 return;
 125
 126         SGPropertyNode *layer_def=NULL;
 127
 128         layer_def = layer_def_root->getChild(name.c_str());
 129         if( !layer_def ) {
 130                 if( name[2] == '-' ) {
 131                         string base_name = name.substr(0,2);
 132                         layer_def = layer_def_root->getChild(base_name.c_str());
 133                 }
 134                 if( !layer_def )
 135                         return;
 136         }
 137
 138         double grid_x_size = layer_def->getDoubleValue("grid-x-size", 1000.0);
 139         double grid_y_size = layer_def->getDoubleValue("grid-y-size", 1000.0);
 140         double grid_x_rand = layer_def->getDoubleValue("grid-x-rand", grid_x_size);
 141         double grid_y_rand = layer_def->getDoubleValue("grid-y-rand", grid_y_size);
 142         double grid_z_rand = layer_def->getDoubleValue("grid-z-rand");
 143
 144         for(int i = 0; i < layer_def->nChildren() ; i++) {
 145                 SGPropertyNode *acloud = layer_def->getChild(i);
 146                 if( strcmp(acloud->getName(), "cloud") == 0) {
 147                         string cloud_name = acloud->getStringValue("name");
 148                         tCloudVariety[CloudVarietyCount].name = cloud_name;
 149                         double count = acloud->getDoubleValue("count", 1.0);
 150                         tCloudVariety[CloudVarietyCount].count = count;
 151                         int variety = 0;
 152                         cloud_name = cloud_name + "-%d";
 153                         char variety_name[50];
 154                         do {
 155                                 variety++;
 156                                 snprintf(variety_name, sizeof(variety_name), cloud_name.c_str(), variety);
 157                         } while( cloud_def_root->getChild(variety_name, 0, false) );
 158
 159                         totalCount += count;
 160                         if( CloudVarietyCount < 20 )
 161                                 CloudVarietyCount++;
 162                 }
 163         }
 164         totalCount = 1.0 / totalCount;
 165         double currCoverage = 0.0;
 166
 167         for(double px = 0.0; px < SGCloudField::fieldSize; px += grid_x_size) {
 168                 for(double py = 0.0; py < SGCloudField::fieldSize; py += grid_y_size) {
 169                         double x = px + grid_x_rand * (sg_random() - 0.5);
 170                         double y = py + grid_y_rand * (sg_random() - 0.5);
 171                         double z = alt + grid_z_rand * (sg_random() - 0.5);
 172                         double choice = sg_random();
 173                         currCoverage += coverage;
 174                         if( currCoverage < 1.0 )
 175                                 continue;
 176                         currCoverage -= 1.0;
 177
 178                         for(int i = 0; i < CloudVarietyCount ; i ++) {
 179                                 choice -= tCloudVariety[i].count * totalCount;
 180                                 if( choice <= 0.0 ) {
 181                                         SGNewCloud *cld = buildCloud(cloud_def_root, tCloudVariety[i].name);
 182                                         sgVec3 pos={x,z,y};
 183                                         if( cld )
 184                                                 layer->addCloud(pos, cld);
 185
 186                                         break;
 187                                 }
 188                         }
 189                 }
 190         }
 191
 192 }
 193
 194 // TODO:call this after real metar updates
 195 void FGClouds::buildMETAR(void) {
 196         SGPropertyNode *metar_root = fgGetNode("/environment", true);
 197
 198         double wind_speed_kt     = metar_root->getDoubleValue("wind-speed-kt");
 199         double temperature_degc  = metar_root->getDoubleValue("temperature-sea-level-degc");
 200         double dewpoint_degc     = metar_root->getDoubleValue("dewpoint-sea-level-degc");
 201         double pressure_mb              = metar_root->getDoubleValue("pressure-sea-level-inhg") * SG_INHG_TO_PA / 100.0;
 202
 203         double dewp = pow(10.0, 7.5 * dewpoint_degc / (237.7 + dewpoint_degc));
 204         double temp = pow(10.0, 7.5 * temperature_degc / (237.7 + temperature_degc));
 205         double rel_humidity = dewp * 100 / temp;
 206
 207         // formule d'Epsy, base d'un cumulus
 208         double cumulus_base = 122.0 * (temperature_degc - dewpoint_degc);
 209         double stratus_base = 100.0 * (100.0 - rel_humidity) * SG_FEET_TO_METER;
 210
 211         bool cu_seen = false;
 212
 213         for(int iLayer = 0 ; iLayer < thesky->get_cloud_layer_count(); iLayer++) {
 214                 SGPropertyNode *cloud_root = fgGetNode("/environment/clouds/layer", iLayer, true);
 215
 216                 double alt_ft = cloud_root->getDoubleValue("elevation-ft");
 217                 double alt_m = alt_ft * SG_FEET_TO_METER;
 218                 string coverage = cloud_root->getStringValue("coverage");
 219                 double coverage_norm = 0.0;
 220                 if( coverage == "few" )
 221                         coverage_norm = 2.0/8.0;        // <1-2
 222                 else if( coverage == "scattered" )
 223                         coverage_norm = 4.0/8.0;        // 3-4
 224                 else if( coverage == "broken" )
 225                         coverage_norm = 6.0/8.0;        // 5-7
 226                 else if( coverage == "overcast" )
 227                         coverage_norm = 8.0/8.0;        // 8
 228
 229                 string layer_type = "nn";
 230                 if( coverage == "cirrus" ) {
 231                         layer_type = "ci";
 232                 } else if( alt_ft > 16500 ) {
 233 //                      layer_type = "ci|cs|cc";
 234                         layer_type = "ci";
 235                 } else if( alt_ft > 6500 ) {
 236 //                      layer_type = "as|ac|ns";
 237                         layer_type = "ac";
 238                         if( pressure_mb < 1005.0 && coverage_norm >= 5.5 )
 239                                 layer_type = "ns";
 240                 } else {
 241 //                      layer_type = "st|cu|cb|sc";
 242                         // +/- 20% from stratus probable base
 243                         if( stratus_base * 0.80 < alt_m && stratus_base * 1.40 > alt_m )
 244                                 layer_type = "st";
 245                         // +/- 20% from cumulus probable base
 246                         else if( cumulus_base * 0.80 < alt_m && cumulus_base * 1.20 > alt_m )
 247                                 layer_type = "cu";
 248                         else {
 249                                 // above formulae is far from perfect
 250                                 if ( alt_ft < 2000 )
 251                                         layer_type = "st";
 252                                 else if( alt_ft < 4500 )
 253                                         layer_type = "cu";
 254                                 else
 255                                         layer_type = "sc";
 256                         }
 257                 }
 258
 259                 SGCloudField *layer3D = thesky->get_cloud_layer(iLayer)->get_layer3D();
 260                 buildLayer(layer3D, layer_type, alt_m, coverage_norm);
 261         }
 262 }
 263
 264 // copy from FGMetarEnvironmentCtrl until better
 265 void
 266 FGClouds::update_metar_properties( FGMetar *m )
 267 {
 268     int i;
 269     double d;
 270     char s[128];
 271
 272     fgSetString("/environment/metar/station-id", m->getId());
 273     fgSetDouble("/environment/metar/min-visibility-m",
 274                 m->getMinVisibility().getVisibility_m() );
 275     fgSetDouble("/environment/metar/max-visibility-m",
 276                 m->getMaxVisibility().getVisibility_m() );
 277
 278     const SGMetarVisibility *dirvis = m->getDirVisibility();
 279     for (i = 0; i < 8; i++, dirvis++) {
 280         const char *min = "/environment/metar/visibility[%d]/min-m";
 281         const char *max = "/environment/metar/visibility[%d]/max-m";
 282
 283         d = dirvis->getVisibility_m();
 284
 285         snprintf(s, 128, min, i);
 286         fgSetDouble(s, d);
 287         snprintf(s, 128, max, i);
 288         fgSetDouble(s, d);
 289     }
 290
 291     fgSetInt("/environment/metar/base-wind-range-from",
 292              m->getWindRangeFrom() );
 293     fgSetInt("/environment/metar/base-wind-range-to",
 294              m->getWindRangeTo() );
 295     fgSetDouble("/environment/metar/base-wind-speed-kt",
 296                 m->getWindSpeed_kt() );
 297     fgSetDouble("/environment/metar/gust-wind-speed-kt",
 298                 m->getGustSpeed_kt() );
 299     fgSetDouble("/environment/metar/temperature-degc",
 300                 m->getTemperature_C() );
 301     fgSetDouble("/environment/metar/dewpoint-degc",
 302                 m->getDewpoint_C() );
 303     fgSetDouble("/environment/metar/rel-humidity-norm",
 304                 m->getRelHumidity() );
 305     fgSetDouble("/environment/metar/pressure-inhg",
 306                 m->getPressure_inHg() );
 307
 308     vector<SGMetarCloud> cv = m->getClouds();
 309     vector<SGMetarCloud>::const_iterator cloud;
 310
 311     const char *cl = "/environment/clouds/layer[%i]";
 312     for (i = 0, cloud = cv.begin(); cloud != cv.end(); cloud++, i++) {
 313         const char *coverage_string[5] =
 314             { "clear", "few", "scattered", "broken", "overcast" };
 315         const double thickness[5] = { 0, 65, 600,750, 1000};
 316         int q;
 317
 318         snprintf(s, 128, cl, i);
 319         strncat(s, "/coverage", 128);
 320         q = cloud->getCoverage();
 321         fgSetString(s, coverage_string[q] );
 322
 323         snprintf(s, 128, cl, i);
 324         strncat(s, "/elevation-ft", 128);
 325         fgSetDouble(s, cloud->getAltitude_ft() + station_elevation_ft);
 326
 327         snprintf(s, 128, cl, i);
 328         strncat(s, "/thickness-ft", 128);
 329         fgSetDouble(s, thickness[q]);
 330
 331         snprintf(s, 128, cl, i);
 332         strncat(s, "/span-m", 128);
 333         fgSetDouble(s, 40000.0);
 334     }
 335
 336     for (; i < FGEnvironmentMgr::MAX_CLOUD_LAYERS; i++) {
 337         snprintf(s, 128, cl, i);
 338         strncat(s, "/coverage", 128);
 339         fgSetString(s, "clear");
 340
 341         snprintf(s, 128, cl, i);
 342         strncat(s, "/elevation-ft", 128);
 343         fgSetDouble(s, -9999);
 344
 345         snprintf(s, 128, cl, i);
 346         strncat(s, "/thickness-ft", 128);
 347         fgSetDouble(s, 0);
 348
 349         snprintf(s, 128, cl, i);
 350         strncat(s, "/span-m", 128);
 351         fgSetDouble(s, 40000.0);
 352     }
 353
 354     fgSetDouble("/environment/metar/rain-norm", m->getRain());
 355     fgSetDouble("/environment/metar/hail-norm", m->getHail());
 356     fgSetDouble("/environment/metar/snow-norm", m->getSnow());
 357     fgSetBool("/environment/metar/snow-cover", m->getSnowCover());
 358 }
 359
 360 void
 361 FGClouds::update_env_config ()
 362 {
 363     fgSetupWind( fgGetDouble("/environment/metar/base-wind-range-from"),
 364                  fgGetDouble("/environment/metar/base-wind-range-to"),
 365                  fgGetDouble("/environment/metar/base-wind-speed-kt"),
 366                  fgGetDouble("/environment/metar/gust-wind-speed-kt") );
 367
 368     fgDefaultWeatherValue( "visibility-m",
 369                            fgGetDouble("/environment/metar/min-visibility-m") );
 370 #if 0
 371     set_temp_at_altitude( fgGetDouble("/environment/metar/temperature-degc"),
 372                           station_elevation_ft );
 373     set_dewpoint_at_altitude( fgGetDouble("/environment/metar/dewpoint-degc"),
 374                               station_elevation_ft );
 375 #endif
 376     fgDefaultWeatherValue( "pressure-sea-level-inhg",
 377                            fgGetDouble("/environment/metar/pressure-inhg") );
 378 }
 379
 380
 381 void FGClouds::setLayer( int iLayer, float alt_ft, const string& coverage, const string& layer_type ) {
 382         double coverage_norm = 0.0;
 383         if( coverage == "few" )
 384                 coverage_norm = 2.0/8.0;        // <1-2
 385         else if( coverage == "scattered" )
 386                 coverage_norm = 4.0/8.0;        // 3-4
 387         else if( coverage == "broken" )
 388                 coverage_norm = 6.0/8.0;        // 5-7
 389         else if( coverage == "overcast" )
 390                 coverage_norm = 8.0/8.0;        // 8
 391
 392         SGCloudField *layer3D = thesky->get_cloud_layer(iLayer)->get_layer3D();
 393         buildLayer(layer3D, layer_type, station_elevation_ft + alt_ft * SG_FEET_TO_METER, coverage_norm);
 394 }
 395
 396 void FGClouds::buildScenario( const string& scenario ) {
 397         string fakeMetar="";
 398         string station = fgGetString("/environment/metar/station-id", "XXXX");
 399
 400         // fetch station elevation if exists
 401     if( station == "XXXX" )
 402         station_elevation_ft = fgGetDouble("/position/ground-elev-m", 0.0);
 403     else {
 404         const FGAirport* a = globals->get_airports()->search( station );
 405         station_elevation_ft = (a ? a->getElevation() : 0.0);
 406     }
 407
 408         for(int iLayer = 0 ; iLayer < thesky->get_cloud_layer_count(); iLayer++) {
 409                 thesky->get_cloud_layer(iLayer)->get_layer3D()->clear();
 410         }
 411
 412         station += " 011000Z ";
 413         if( scenario == "Fair weather" ) {
 414                 fakeMetar = "15003KT 12SM SCT033 FEW200 20/08 Q1015 NOSIG";
 415                 setLayer(0, 3300.0, "scattered", "cu");
 416         } else if( scenario == "Thunderstorm" ) {
 417                 fakeMetar = "15012KT 08SM TSRA SCT040 BKN070 20/12 Q0995";
 418                 setLayer(0, 4000.0, "scattered", "cb");
 419                 setLayer(1, 7000.0, "scattered", "ns");
 420         } else
 421                 return;
 422         FGMetar *m = new FGMetar( station + fakeMetar );
 423         update_metar_properties( m );
 424         update_env_config();
 425         // propagate aloft tables
 426         _controller->reinit();
 427
 428         fgSetString("/environment/metar/last-metar", m->getData());
 429         // TODO:desactivate real metar updates
 430         if( scenario == "Fair weather" ) {
 431                 fgSetString("/environment/clouds/layer[1]/coverage", "cirrus");
 432         }
 433 }
 434
 435
 436 void FGClouds::build(void) {
 437         string scenario = fgGetString("/environment/weather-scenario", "METAR");
 438
 439     if( scenario == last_scenario)
 440         return;
 441     if( last_scenario == "none" ) {
 442         // save clouds and weather conditions
 443         SGPropertyNode *param = fgGetNode("/environment/config", true);
 444         copyProperties( param, last_env_config );
 445         param = fgGetNode("/environment/clouds", true);
 446         copyProperties( param, last_env_clouds );
 447     }
 448         if( scenario == "METAR" ) {
 449                 string realMetar = fgGetString("/environment/metar/real-metar", "");
 450                 if( realMetar != "" ) {
 451                         fgSetString("/environment/metar/last-metar", realMetar.c_str());
 452                         FGMetar *m = new FGMetar( realMetar );
 453                         update_metar_properties( m );
 454                         update_env_config();
 455                         // propagate aloft tables
 456                         _controller->reinit();
 457                 }
 458                 buildMETAR();
 459         }
 460     else if( scenario == "none" ) {
 461         // restore clouds and weather conditions
 462         SGPropertyNode *param = fgGetNode("/environment/config", true);
 463         copyProperties( last_env_config, param );
 464         param = fgGetNode("/environment/clouds", true);
 465         copyProperties( last_env_clouds, param );
 466         fgSetDouble("/environment/metar/rain-norm", 0.0);
 467         fgSetDouble("/environment/metar/snow-norm", 0.0);
 468 //          update_env_config();
 469             // propagate aloft tables
 470             _controller->reinit();
 471                 buildMETAR();
 472     }
 473         else
 474                 buildScenario( scenario );
 475     last_scenario = scenario;
 476
 477         // ...
 478         if( snd_lightning == NULL )
 479                 init();
 480 }