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, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
  20 //
  21 //
  22
  23 #ifdef HAVE_CONFIG_H
  24 #  include "config.h"
  25 #endif
  26
  27 #include <Main/fg_props.hxx>
  28
  29 #include <simgear/constants.h>
  30 #include <simgear/sound/soundmgr_openal.hxx>
  31 #include <simgear/scene/sky/sky.hxx>
  32 #include <simgear/environment/visual_enviro.hxx>
  33 #include <simgear/scene/sky/cloudfield.hxx>
  34 #include <simgear/scene/sky/newcloud.hxx>
  35 #include <simgear/math/sg_random.h>
  36 #include <simgear/props/props_io.hxx>
  37
  38 #include <Main/globals.hxx>
  39 #include <Airports/simple.hxx>
  40 #include <Main/util.hxx>
  41
  42 #include "environment_ctrl.hxx"
  43 #include "environment_mgr.hxx"
  44 #include "fgmetar.hxx"
  45 #include "fgclouds.hxx"
  46
  47 extern SGSky *thesky;
  48
  49
  50 FGClouds::FGClouds(FGEnvironmentCtrl * controller) :
  51         station_elevation_ft(0.0),
  52         _controller( controller ),
  53         snd_lightning(NULL),
  54     last_scenario( "none" ),
  55     last_env_config( new SGPropertyNode() ),
  56     last_env_clouds( new SGPropertyNode() )
  57 {
  58         update_event = 0;
  59         fgSetString("/environment/weather-scenario", last_scenario.c_str());
  60 }
  61 FGClouds::~FGClouds() {
  62 }
  63
  64 int FGClouds::get_update_event(void) const {
  65         return update_event;
  66 }
  67 void FGClouds::set_update_event(int count) {
  68         update_event = count;
  69         build();
  70 }
  71
  72 void FGClouds::init(void) {
  73         if( snd_lightning == NULL ) {
  74                 snd_lightning = new SGSoundSample(globals->get_fg_root().c_str(), "Sounds/thunder.wav");
  75                 snd_lightning->set_max_dist(7000.0f);
  76                 snd_lightning->set_reference_dist(3000.0f);
  77                 SGSoundMgr *soundMgr = globals->get_soundmgr();
  78                 soundMgr->add( snd_lightning, "thunder" );
  79                 sgEnviro.set_soundMgr( soundMgr );
  80         }
  81 }
  82
  83 SGNewCloud *FGClouds::buildCloud(SGPropertyNode *cloud_def_root, const string& name) {
  84         SGPropertyNode *cld_def=NULL;
  85
  86         cld_def = cloud_def_root->getChild(name.c_str());
  87         string base_name = name.substr(0,2);
  88         if( !cld_def ) {
  89                 if( name[2] == '-' ) {
  90                         cld_def = cloud_def_root->getChild(base_name.c_str());
  91                 }
  92                 if( !cld_def )
  93                         return NULL;
  94         }
  95         string familly = cld_def->getStringValue("familly", base_name.c_str());
  96         SGNewCloud *cld = new SGNewCloud(familly);
  97         for(int i = 0; i < cld_def->nChildren() ; i++) {
  98                 SGPropertyNode *abox = cld_def->getChild(i);
  99                 if( strcmp(abox->getName(), "box") == 0) {
 100                         double x = abox->getDoubleValue("x");
 101                         double y = abox->getDoubleValue("y");
 102                         double z = abox->getDoubleValue("z");
 103                         double size = abox->getDoubleValue("size");
 104                         int type = abox->getIntValue("type", SGNewCloud::CLbox_standard);
 105                         cld->addContainer(x, y, z, size, (SGNewCloud::CLbox_type) type);
 106                 }
 107         }
 108         cld->genSprites();
 109         return cld;
 110 }
 111
 112 void FGClouds::buildLayer(SGCloudField *layer, const string& name, double alt, double coverage) {
 113         struct {
 114                 string name;
 115                 double count;
 116         } tCloudVariety[20];
 117         int CloudVarietyCount = 0;
 118         double totalCount = 0.0;
 119
 120         SGPropertyNode *cloud_def_root = fgGetNode("/environment/cloudlayers/clouds", false);
 121         SGPropertyNode *layer_def_root = fgGetNode("/environment/cloudlayers/layers", false);
 122
 123         layer->clear();
 124         // when we don't generate clouds the layer is rendered in 2D
 125         if( coverage == 0.0 )
 126                 return;
 127         if( layer_def_root == NULL || cloud_def_root == NULL)
 128                 return;
 129         if( name == "ci" || name == "sc" || name == "st")
 130                 return;
 131
 132         SGPropertyNode *layer_def=NULL;
 133
 134         layer_def = layer_def_root->getChild(name.c_str());
 135         if( !layer_def ) {
 136                 if( name[2] == '-' ) {
 137                         string base_name = name.substr(0,2);
 138                         layer_def = layer_def_root->getChild(base_name.c_str());
 139                 }
 140                 if( !layer_def )
 141                         return;
 142         }
 143
 144         double grid_x_size = layer_def->getDoubleValue("grid-x-size", 1000.0);
 145         double grid_y_size = layer_def->getDoubleValue("grid-y-size", 1000.0);
 146         double grid_x_rand = layer_def->getDoubleValue("grid-x-rand", grid_x_size);
 147         double grid_y_rand = layer_def->getDoubleValue("grid-y-rand", grid_y_size);
 148         double grid_z_rand = layer_def->getDoubleValue("grid-z-rand");
 149
 150         for(int i = 0; i < layer_def->nChildren() ; i++) {
 151                 SGPropertyNode *acloud = layer_def->getChild(i);
 152                 if( strcmp(acloud->getName(), "cloud") == 0) {
 153                         string cloud_name = acloud->getStringValue("name");
 154                         tCloudVariety[CloudVarietyCount].name = cloud_name;
 155                         double count = acloud->getDoubleValue("count", 1.0);
 156                         tCloudVariety[CloudVarietyCount].count = count;
 157                         int variety = 0;
 158                         cloud_name = cloud_name + "-%d";
 159                         char variety_name[50];
 160                         do {
 161                                 variety++;
 162                                 snprintf(variety_name, sizeof(variety_name), cloud_name.c_str(), variety);
 163                         } while( cloud_def_root->getChild(variety_name, 0, false) );
 164
 165                         totalCount += count;
 166                         if( CloudVarietyCount < 20 )
 167                                 CloudVarietyCount++;
 168                 }
 169         }
 170         totalCount = 1.0 / totalCount;
 171         double currCoverage = 0.0;
 172
 173         for(double px = 0.0; px < SGCloudField::fieldSize; px += grid_x_size) {
 174                 for(double py = 0.0; py < SGCloudField::fieldSize; py += grid_y_size) {
 175                         double x = px + grid_x_rand * (sg_random() - 0.5);
 176                         double y = py + grid_y_rand * (sg_random() - 0.5);
 177                         double z = alt + grid_z_rand * (sg_random() - 0.5);
 178                         double choice = sg_random();
 179                         currCoverage += coverage;
 180                         if( currCoverage < 1.0 )
 181                                 continue;
 182                         currCoverage -= 1.0;
 183
 184                         for(int i = 0; i < CloudVarietyCount ; i ++) {
 185                                 choice -= tCloudVariety[i].count * totalCount;
 186                                 if( choice <= 0.0 ) {
 187                                         SGNewCloud *cld = buildCloud(cloud_def_root, tCloudVariety[i].name);
 188                                         sgVec3 pos={x,z,y};
 189                                         if( cld )
 190                                                 layer->addCloud(pos, cld);
 191
 192                                         break;
 193                                 }
 194                         }
 195                 }
 196         }
 197
 198 }
 199
 200 // TODO:call this after real metar updates
 201 void FGClouds::buildMETAR(void) {
 202         SGPropertyNode *metar_root = fgGetNode("/environment", true);
 203
 204         double wind_speed_kt     = metar_root->getDoubleValue("wind-speed-kt");
 205         double temperature_degc  = metar_root->getDoubleValue("temperature-sea-level-degc");
 206         double dewpoint_degc     = metar_root->getDoubleValue("dewpoint-sea-level-degc");
 207         double pressure_mb              = metar_root->getDoubleValue("pressure-sea-level-inhg") * SG_INHG_TO_PA / 100.0;
 208
 209         double dewp = pow(10.0, 7.5 * dewpoint_degc / (237.7 + dewpoint_degc));
 210         double temp = pow(10.0, 7.5 * temperature_degc / (237.7 + temperature_degc));
 211         double rel_humidity = dewp * 100 / temp;
 212
 213         // formule d'Epsy, base d'un cumulus
 214         double cumulus_base = 122.0 * (temperature_degc - dewpoint_degc);
 215         double stratus_base = 100.0 * (100.0 - rel_humidity) * SG_FEET_TO_METER;
 216
 217         bool cu_seen = false;
 218
 219         for(int iLayer = 0 ; iLayer < thesky->get_cloud_layer_count(); iLayer++) {
 220                 SGPropertyNode *cloud_root = fgGetNode("/environment/clouds/layer", iLayer, true);
 221
 222                 double alt_ft = cloud_root->getDoubleValue("elevation-ft");
 223                 double alt_m = alt_ft * SG_FEET_TO_METER;
 224                 string coverage = cloud_root->getStringValue("coverage");
 225                 double coverage_norm = 0.0;
 226                 if( coverage == "few" )
 227                         coverage_norm = 2.0/8.0;        // <1-2
 228                 else if( coverage == "scattered" )
 229                         coverage_norm = 4.0/8.0;        // 3-4
 230                 else if( coverage == "broken" )
 231                         coverage_norm = 6.0/8.0;        // 5-7
 232                 else if( coverage == "overcast" )
 233                         coverage_norm = 8.0/8.0;        // 8
 234
 235                 string layer_type = "nn";
 236                 if( coverage == "cirrus" ) {
 237                         layer_type = "ci";
 238                 } else if( alt_ft > 16500 ) {
 239 //                      layer_type = "ci|cs|cc";
 240                         layer_type = "ci";
 241                 } else if( alt_ft > 6500 ) {
 242 //                      layer_type = "as|ac|ns";
 243                         layer_type = "ac";
 244                         if( pressure_mb < 1005.0 && coverage_norm >= 5.5 )
 245                                 layer_type = "ns";
 246                 } else {
 247 //                      layer_type = "st|cu|cb|sc";
 248                         // +/- 20% from stratus probable base
 249                         if( stratus_base * 0.80 < alt_m && stratus_base * 1.40 > alt_m )
 250                                 layer_type = "st";
 251                         // +/- 20% from cumulus probable base
 252                         else if( cumulus_base * 0.80 < alt_m && cumulus_base * 1.20 > alt_m )
 253                                 layer_type = "cu";
 254                         else {
 255                                 // above formulae is far from perfect
 256                                 if ( alt_ft < 2000 )
 257                                         layer_type = "st";
 258                                 else if( alt_ft < 4500 )
 259                                         layer_type = "cu";
 260                                 else
 261                                         layer_type = "sc";
 262                         }
 263                 }
 264
 265                 SGCloudField *layer3D = thesky->get_cloud_layer(iLayer)->get_layer3D();
 266                 buildLayer(layer3D, layer_type, alt_m, coverage_norm);
 267         }
 268 }
 269
 270 // copy from FGMetarEnvironmentCtrl until better
 271 void
 272 FGClouds::update_metar_properties( const FGMetar *m )
 273 {
 274     int i;
 275     double d;
 276     char s[128];
 277
 278     fgSetString("/environment/metar/station-id", m->getId());
 279     fgSetDouble("/environment/metar/min-visibility-m",
 280                 m->getMinVisibility().getVisibility_m() );
 281     fgSetDouble("/environment/metar/max-visibility-m",
 282                 m->getMaxVisibility().getVisibility_m() );
 283
 284     const SGMetarVisibility *dirvis = m->getDirVisibility();
 285     for (i = 0; i < 8; i++, dirvis++) {
 286         const char *min = "/environment/metar/visibility[%d]/min-m";
 287         const char *max = "/environment/metar/visibility[%d]/max-m";
 288
 289         d = dirvis->getVisibility_m();
 290
 291         snprintf(s, 128, min, i);
 292         fgSetDouble(s, d);
 293         snprintf(s, 128, max, i);
 294         fgSetDouble(s, d);
 295     }
 296
 297     fgSetInt("/environment/metar/base-wind-range-from",
 298              m->getWindRangeFrom() );
 299     fgSetInt("/environment/metar/base-wind-range-to",
 300              m->getWindRangeTo() );
 301     fgSetDouble("/environment/metar/base-wind-speed-kt",
 302                 m->getWindSpeed_kt() );
 303     fgSetDouble("/environment/metar/gust-wind-speed-kt",
 304                 m->getGustSpeed_kt() );
 305     fgSetDouble("/environment/metar/temperature-degc",
 306                 m->getTemperature_C() );
 307     fgSetDouble("/environment/metar/dewpoint-degc",
 308                 m->getDewpoint_C() );
 309     fgSetDouble("/environment/metar/rel-humidity-norm",
 310                 m->getRelHumidity() );
 311     fgSetDouble("/environment/metar/pressure-inhg",
 312                 m->getPressure_inHg() );
 313
 314     vector<SGMetarCloud> cv = m->getClouds();
 315     vector<SGMetarCloud>::const_iterator cloud;
 316
 317     const char *cl = "/environment/clouds/layer[%i]";
 318     for (i = 0, cloud = cv.begin(); cloud != cv.end(); cloud++, i++) {
 319         const char *coverage_string[5] =
 320             { "clear", "few", "scattered", "broken", "overcast" };
 321         const double thickness[5] = { 0, 65, 600,750, 1000};
 322         int q;
 323
 324         snprintf(s, 128, cl, i);
 325         strncat(s, "/coverage", 128);
 326         q = cloud->getCoverage();
 327         fgSetString(s, coverage_string[q] );
 328
 329         snprintf(s, 128, cl, i);
 330         strncat(s, "/elevation-ft", 128);
 331         fgSetDouble(s, cloud->getAltitude_ft() + station_elevation_ft);
 332
 333         snprintf(s, 128, cl, i);
 334         strncat(s, "/thickness-ft", 128);
 335         fgSetDouble(s, thickness[q]);
 336
 337         snprintf(s, 128, cl, i);
 338         strncat(s, "/span-m", 128);
 339         fgSetDouble(s, 40000.0);
 340     }
 341
 342     for (; i < FGEnvironmentMgr::MAX_CLOUD_LAYERS; i++) {
 343         snprintf(s, 128, cl, i);
 344         strncat(s, "/coverage", 128);
 345         fgSetString(s, "clear");
 346
 347         snprintf(s, 128, cl, i);
 348         strncat(s, "/elevation-ft", 128);
 349         fgSetDouble(s, -9999);
 350
 351         snprintf(s, 128, cl, i);
 352         strncat(s, "/thickness-ft", 128);
 353         fgSetDouble(s, 0);
 354
 355         snprintf(s, 128, cl, i);
 356         strncat(s, "/span-m", 128);
 357         fgSetDouble(s, 40000.0);
 358     }
 359
 360     fgSetDouble("/environment/metar/rain-norm", m->getRain());
 361     fgSetDouble("/environment/metar/hail-norm", m->getHail());
 362     fgSetDouble("/environment/metar/snow-norm", m->getSnow());
 363     fgSetBool("/environment/metar/snow-cover", m->getSnowCover());
 364 }
 365
 366 void
 367 FGClouds::update_env_config ()
 368 {
 369     fgSetupWind( fgGetDouble("/environment/metar/base-wind-range-from"),
 370                  fgGetDouble("/environment/metar/base-wind-range-to"),
 371                  fgGetDouble("/environment/metar/base-wind-speed-kt"),
 372                  fgGetDouble("/environment/metar/gust-wind-speed-kt") );
 373
 374     fgDefaultWeatherValue( "visibility-m",
 375                            fgGetDouble("/environment/metar/min-visibility-m") );
 376 #if 0
 377     set_temp_at_altitude( fgGetDouble("/environment/metar/temperature-degc"),
 378                           station_elevation_ft );
 379     set_dewpoint_at_altitude( fgGetDouble("/environment/metar/dewpoint-degc"),
 380                               station_elevation_ft );
 381 #endif
 382     fgDefaultWeatherValue( "pressure-sea-level-inhg",
 383                            fgGetDouble("/environment/metar/pressure-inhg") );
 384 }
 385
 386
 387 void FGClouds::setLayer( int iLayer, float alt_ft, const string& coverage, const string& layer_type ) {
 388         double coverage_norm = 0.0;
 389         if( coverage == "few" )
 390                 coverage_norm = 2.0/8.0;        // <1-2
 391         else if( coverage == "scattered" )
 392                 coverage_norm = 4.0/8.0;        // 3-4
 393         else if( coverage == "broken" )
 394                 coverage_norm = 6.0/8.0;        // 5-7
 395         else if( coverage == "overcast" )
 396                 coverage_norm = 8.0/8.0;        // 8
 397
 398         SGCloudField *layer3D = thesky->get_cloud_layer(iLayer)->get_layer3D();
 399         buildLayer(layer3D, layer_type, station_elevation_ft + alt_ft * SG_FEET_TO_METER, coverage_norm);
 400 }
 401
 402 void FGClouds::buildScenario( const string& scenario ) {
 403         string fakeMetar="";
 404         string station = fgGetString("/environment/metar/station-id", "XXXX");
 405
 406         // fetch station elevation if exists
 407     if( station == "XXXX" )
 408         station_elevation_ft = fgGetDouble("/position/ground-elev-m", 0.0);
 409     else {
 410         const FGAirport* a = globals->get_airports()->search( station );
 411         station_elevation_ft = (a ? a->getElevation() : 0.0);
 412     }
 413
 414         for(int iLayer = 0 ; iLayer < thesky->get_cloud_layer_count(); iLayer++) {
 415             thesky->get_cloud_layer(iLayer)
 416                 ->setCoverage(SGCloudLayer::SG_CLOUD_CLEAR);
 417             thesky->get_cloud_layer(iLayer)->get_layer3D()->clear();
 418         }
 419
 420         station += " 011000Z ";
 421         if( scenario == "Fair weather" ) {
 422                 fakeMetar = "15003KT 12SM SCT033 FEW200 20/08 Q1015 NOSIG";
 423                 setLayer(0, 3300.0, "scattered", "cu");
 424         } else if( scenario == "Thunderstorm" ) {
 425                 fakeMetar = "15012KT 08SM TSRA SCT040 BKN070 20/12 Q0995";
 426                 setLayer(0, 4000.0, "scattered", "cb");
 427                 setLayer(1, 7000.0, "scattered", "ns");
 428         } else
 429                 return;
 430         FGMetar *m = new FGMetar( station + fakeMetar );
 431         update_metar_properties( m );
 432         update_env_config();
 433         // propagate aloft tables
 434         _controller->reinit();
 435
 436         fgSetString("/environment/metar/last-metar", m->getData());
 437         // TODO:desactivate real metar updates
 438         if( scenario == "Fair weather" ) {
 439                 fgSetString("/environment/clouds/layer[1]/coverage", "cirrus");
 440         }
 441 }
 442
 443
 444 void FGClouds::build(void) {
 445         string scenario = fgGetString("/environment/weather-scenario", "METAR");
 446
 447     if( scenario == last_scenario)
 448         return;
 449     if( last_scenario == "none" ) {
 450         // save clouds and weather conditions
 451         SGPropertyNode *param = fgGetNode("/environment/config", true);
 452         copyProperties( param, last_env_config );
 453         param = fgGetNode("/environment/clouds", true);
 454         copyProperties( param, last_env_clouds );
 455     }
 456         if( scenario == "METAR" ) {
 457                 string realMetar = fgGetString("/environment/metar/real-metar", "");
 458                 if( realMetar != "" ) {
 459                         fgSetString("/environment/metar/last-metar", realMetar.c_str());
 460                         FGMetar *m = new FGMetar( realMetar );
 461                         update_metar_properties( m );
 462                         update_env_config();
 463                         // propagate aloft tables
 464                         _controller->reinit();
 465                 }
 466                 buildMETAR();
 467         }
 468     else if( scenario == "none" ) {
 469         // restore clouds and weather conditions
 470         SGPropertyNode *param = fgGetNode("/environment/config", true);
 471         copyProperties( last_env_config, param );
 472         param = fgGetNode("/environment/clouds", true);
 473         copyProperties( last_env_clouds, param );
 474         fgSetDouble("/environment/metar/rain-norm", 0.0);
 475         fgSetDouble("/environment/metar/snow-norm", 0.0);
 476 //          update_env_config();
 477             // propagate aloft tables
 478             _controller->reinit();
 479                 buildMETAR();
 480     }
 481         else
 482                 buildScenario( scenario );
 483     last_scenario = scenario;
 484
 485         // ...
 486         if( snd_lightning == NULL )
 487                 init();
 488 }