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