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