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 void FGClouds::buildCloud(SGPropertyNode *cloud_def_root, SGPropertyNode  *box_def_root, const string& name, sgVec3 pos, SGCloudField *layer) {
  84         SGPropertyNode *box_def=NULL;
  85         SGPropertyNode *cld_def=NULL;
  86
  87         SGPath texture_root = globals->get_fg_root();
  88         texture_root.append("Textures");
  89         texture_root.append("Sky");
  90
  91         box_def = box_def_root->getChild(name.c_str());
  92
  93         string base_name = name.substr(0,2);
  94         if( !box_def ) {
  95                 if( name[2] == '-' ) {
  96                         box_def = box_def_root->getChild(base_name.c_str());
  97                 }
  98                 if( !box_def )
  99                         return;
 100         }
 101
 102         for(int i = 0; i < box_def->nChildren() ; i++) {
 103                 SGPropertyNode *abox = box_def->getChild(i);
 104                 if( strcmp(abox->getName(), "box") == 0) {
 105                         double x = abox->getDoubleValue("x") + pos[0];
 106                         double y = abox->getDoubleValue("y") + pos[1];
 107                         double z = abox->getDoubleValue("z") + pos[2];
 108                         SGVec3f newpos = SGVec3f(x, z, y);
 109
 110                         string type = abox->getStringValue("type", "cu-small");
 111
 112                         cld_def = cloud_def_root->getChild(type.c_str());
 113                         if ( !cld_def ) return;
 114
 115                         double min_width = cld_def->getDoubleValue("min-cloud-width-m", 500.0);
 116                         double max_width = cld_def->getDoubleValue("max-cloud-width-m", 1000.0);
 117                         double min_height = cld_def->getDoubleValue("min-cloud-height-m", min_width);
 118                         double max_height = cld_def->getDoubleValue("max-cloud-height-m", max_width);
 119                         double min_sprite_width = cld_def->getDoubleValue("min-sprite-width-m", 200.0);
 120                         double max_sprite_width = cld_def->getDoubleValue("max-sprite-width-m", min_sprite_width);
 121                         double min_sprite_height = cld_def->getDoubleValue("min-sprite-height-m", min_sprite_width);
 122                         double max_sprite_height = cld_def->getDoubleValue("max-sprite-height-m", max_sprite_width);
 123                         int num_sprites = cld_def->getIntValue("num-sprites", 20);
 124                         int num_textures_x = cld_def->getIntValue("num-textures-x", 1);
 125                         int num_textures_y = cld_def->getIntValue("num-textures-y", 1);
 126                         double bottom_shade = cld_def->getDoubleValue("bottom-shade", 1.0);
 127                         string texture = cld_def->getStringValue("texture", "cl_cumulus.rgb");
 128
 129                         SGNewCloud *cld =
 130                                 new SGNewCloud(texture_root,
 131                                                texture,
 132                                                min_width,
 133                                                max_width,
 134                                                min_height,
 135                                                max_height,
 136                                                min_sprite_width,
 137                                                max_sprite_width,
 138                                                min_sprite_height,
 139                                                max_sprite_height,
 140                                                bottom_shade,
 141                                                num_sprites,
 142                                                num_textures_x,
 143                                                num_textures_y);
 144                         layer->addCloud(newpos, cld);
 145                 }
 146         }
 147 }
 148
 149 void FGClouds::buildLayer(int iLayer, const string& name, double alt, double coverage) {
 150         struct {
 151                 string name;
 152                 double count;
 153         } tCloudVariety[20];
 154         int CloudVarietyCount = 0;
 155         double totalCount = 0.0;
 156
 157         SGPropertyNode *cloud_def_root = fgGetNode("/environment/cloudlayers/clouds", false);
 158         SGPropertyNode *box_def_root   = fgGetNode("/environment/cloudlayers/boxes", false);
 159         SGPropertyNode *layer_def_root = fgGetNode("/environment/cloudlayers/layers", false);
 160         SGCloudField *layer = thesky->get_cloud_layer(iLayer)->get_layer3D();
 161
 162         layer->clear();
 163         // when we don't generate clouds the layer is rendered in 2D
 164         if( coverage == 0.0 )
 165                 return;
 166         if( layer_def_root == NULL || cloud_def_root == NULL || box_def_root == NULL)
 167                 return;
 168
 169         SGPropertyNode *layer_def=NULL;
 170
 171         layer_def = layer_def_root->getChild(name.c_str());
 172         if( !layer_def ) {
 173                 if( name[2] == '-' ) {
 174                         string base_name = name.substr(0,2);
 175                         layer_def = layer_def_root->getChild(base_name.c_str());
 176                 }
 177                 if( !layer_def )
 178                         return;
 179         }
 180
 181         double grid_x_size = layer_def->getDoubleValue("grid-x-size", 1000.0);
 182         double grid_y_size = layer_def->getDoubleValue("grid-y-size", 1000.0);
 183         double grid_x_rand = layer_def->getDoubleValue("grid-x-rand", grid_x_size);
 184         double grid_y_rand = layer_def->getDoubleValue("grid-y-rand", grid_y_size);
 185         double grid_z_rand = layer_def->getDoubleValue("grid-z-rand");
 186
 187         for(int i = 0; i < layer_def->nChildren() ; i++) {
 188                 SGPropertyNode *acloud = layer_def->getChild(i);
 189                 if( strcmp(acloud->getName(), "cloud") == 0) {
 190                         string cloud_name = acloud->getStringValue("name");
 191                         tCloudVariety[CloudVarietyCount].name = cloud_name;
 192                         double count = acloud->getDoubleValue("count", 1.0);
 193                         tCloudVariety[CloudVarietyCount].count = count;
 194                         int variety = 0;
 195                         cloud_name = cloud_name + "-%d";
 196                         char variety_name[50];
 197                         do {
 198                                 variety++;
 199                                 snprintf(variety_name, sizeof(variety_name), cloud_name.c_str(), variety);
 200                         } while( box_def_root->getChild(variety_name, 0, false) );
 201
 202                         totalCount += count;
 203                         if( CloudVarietyCount < 20 )
 204                                 CloudVarietyCount++;
 205                 }
 206         }
 207         totalCount = 1.0 / totalCount;
 208         double currCoverage = 0.0;
 209
 210         for(double px = 0.0; px < SGCloudField::fieldSize; px += grid_x_size) {
 211                 for(double py = 0.0; py < SGCloudField::fieldSize; py += grid_y_size) {
 212                         double x = px + grid_x_rand * (sg_random() - 0.5) - (SGCloudField::fieldSize / 2.0);
 213                         double y = py + grid_y_rand * (sg_random() - 0.5) - (SGCloudField::fieldSize / 2.0);
 214                         double z = alt + grid_z_rand * (sg_random() - 0.5);
 215                         double choice = sg_random();
 216                         currCoverage += coverage;
 217                         if( currCoverage < 1.0 )
 218                                 continue;
 219                         currCoverage -= 1.0;
 220
 221                         for(int i = 0; i < CloudVarietyCount ; i ++) {
 222                                 choice -= tCloudVariety[i].count * totalCount;
 223                                 if( choice <= 0.0 ) {
 224                                         sgVec3 pos={x,z,y};
 225
 226                                         buildCloud(cloud_def_root, box_def_root, tCloudVariety[i].name, pos, layer);
 227                                         break;
 228                                 }
 229                         }
 230                 }
 231         }
 232
 233         // Now we've built any clouds, enable them
 234         thesky->get_cloud_layer(iLayer)->set_enable3dClouds(thesky->get_3dClouds());
 235 }
 236
 237 // TODO:call this after real metar updates
 238 void FGClouds::buildMETAR(void) {
 239         SGPropertyNode *metar_root = fgGetNode("/environment", true);
 240
 241         double wind_speed_kt     = metar_root->getDoubleValue("wind-speed-kt");
 242         double temperature_degc  = metar_root->getDoubleValue("temperature-sea-level-degc");
 243         double dewpoint_degc     = metar_root->getDoubleValue("dewpoint-sea-level-degc");
 244         double pressure_mb              = metar_root->getDoubleValue("pressure-sea-level-inhg") * SG_INHG_TO_PA / 100.0;
 245
 246         double dewp = pow(10.0, 7.5 * dewpoint_degc / (237.7 + dewpoint_degc));
 247         double temp = pow(10.0, 7.5 * temperature_degc / (237.7 + temperature_degc));
 248         double rel_humidity = dewp * 100 / temp;
 249
 250         // formule d'Epsy, base d'un cumulus
 251         double cumulus_base = 122.0 * (temperature_degc - dewpoint_degc);
 252         double stratus_base = 100.0 * (100.0 - rel_humidity) * SG_FEET_TO_METER;
 253
 254         bool cu_seen = false;
 255
 256         for(int iLayer = 0 ; iLayer < thesky->get_cloud_layer_count(); iLayer++) {
 257                 SGPropertyNode *cloud_root = fgGetNode("/environment/clouds/layer", iLayer, true);
 258
 259                 double alt_ft = cloud_root->getDoubleValue("elevation-ft");
 260                 double alt_m = alt_ft * SG_FEET_TO_METER;
 261                 string coverage = cloud_root->getStringValue("coverage");
 262                 double coverage_norm = 0.0;
 263                 if( coverage == "few" )
 264                         coverage_norm = 2.0/8.0;        // <1-2
 265                 else if( coverage == "scattered" )
 266                         coverage_norm = 4.0/8.0;        // 3-4
 267                 else if( coverage == "broken" )
 268                         coverage_norm = 6.0/8.0;        // 5-7
 269                 else if( coverage == "overcast" )
 270                         coverage_norm = 8.0/8.0;        // 8
 271
 272                 string layer_type = "nn";
 273                 if( coverage == "cirrus" ) {
 274                         layer_type = "ci";
 275                 } else if( alt_ft > 16500 ) {
 276 //                      layer_type = "ci|cs|cc";
 277                         layer_type = "ci";
 278                 } else if( alt_ft > 6500 ) {
 279 //                      layer_type = "as|ac|ns";
 280                         layer_type = "ac";
 281                         if( pressure_mb < 1005.0 && coverage_norm >= 5.5 )
 282                                 layer_type = "ns";
 283                 } else {
 284 //                      layer_type = "st|cu|cb|sc";
 285                         // +/- 20% from stratus probable base
 286                         if( stratus_base * 0.80 < alt_m && stratus_base * 1.40 > alt_m )
 287                                 layer_type = "st";
 288                         // +/- 20% from cumulus probable base
 289                         else if( cumulus_base * 0.80 < alt_m && cumulus_base * 1.20 > alt_m )
 290                                 layer_type = "cu";
 291                         else {
 292                                 // above formulae is far from perfect
 293                                 if ( alt_ft < 2000 )
 294                                         layer_type = "st";
 295                                 else if( alt_ft < 4500 )
 296                                         layer_type = "cu";
 297                                 else
 298                                         layer_type = "sc";
 299                         }
 300                 }
 301
 302                 buildLayer(iLayer, layer_type, alt_m, coverage_norm);
 303         }
 304 }
 305
 306 // copy from FGMetarEnvironmentCtrl until better
 307 void
 308 FGClouds::update_metar_properties( const FGMetar *m )
 309 {
 310     int i;
 311     double d;
 312     char s[128];
 313
 314     fgSetString("/environment/metar/station-id", m->getId());
 315     fgSetDouble("/environment/metar/min-visibility-m",
 316                 m->getMinVisibility().getVisibility_m() );
 317     fgSetDouble("/environment/metar/max-visibility-m",
 318                 m->getMaxVisibility().getVisibility_m() );
 319
 320     const SGMetarVisibility *dirvis = m->getDirVisibility();
 321     for (i = 0; i < 8; i++, dirvis++) {
 322         const char *min = "/environment/metar/visibility[%d]/min-m";
 323         const char *max = "/environment/metar/visibility[%d]/max-m";
 324
 325         d = dirvis->getVisibility_m();
 326
 327         snprintf(s, 128, min, i);
 328         fgSetDouble(s, d);
 329         snprintf(s, 128, max, i);
 330         fgSetDouble(s, d);
 331     }
 332
 333     fgSetInt("/environment/metar/base-wind-range-from",
 334              m->getWindRangeFrom() );
 335     fgSetInt("/environment/metar/base-wind-range-to",
 336              m->getWindRangeTo() );
 337     fgSetDouble("/environment/metar/base-wind-speed-kt",
 338                 m->getWindSpeed_kt() );
 339     fgSetDouble("/environment/metar/gust-wind-speed-kt",
 340                 m->getGustSpeed_kt() );
 341     fgSetDouble("/environment/metar/temperature-degc",
 342                 m->getTemperature_C() );
 343     fgSetDouble("/environment/metar/dewpoint-degc",
 344                 m->getDewpoint_C() );
 345     fgSetDouble("/environment/metar/rel-humidity-norm",
 346                 m->getRelHumidity() );
 347     fgSetDouble("/environment/metar/pressure-inhg",
 348                 m->getPressure_inHg() );
 349
 350     vector<SGMetarCloud> cv = m->getClouds();
 351     vector<SGMetarCloud>::const_iterator cloud;
 352
 353     const char *cl = "/environment/clouds/layer[%i]";
 354     for (i = 0, cloud = cv.begin(); cloud != cv.end(); cloud++, i++) {
 355         const char *coverage_string[5] =
 356             { "clear", "few", "scattered", "broken", "overcast" };
 357         const double thickness[5] = { 0, 65, 600,750, 1000};
 358         int q;
 359
 360         snprintf(s, 128, cl, i);
 361         strncat(s, "/coverage", 128);
 362         q = cloud->getCoverage();
 363         fgSetString(s, coverage_string[q] );
 364
 365         snprintf(s, 128, cl, i);
 366         strncat(s, "/elevation-ft", 128);
 367         fgSetDouble(s, cloud->getAltitude_ft() + station_elevation_ft);
 368
 369         snprintf(s, 128, cl, i);
 370         strncat(s, "/thickness-ft", 128);
 371         fgSetDouble(s, thickness[q]);
 372
 373         snprintf(s, 128, cl, i);
 374         strncat(s, "/span-m", 128);
 375         fgSetDouble(s, 40000.0);
 376     }
 377
 378     for (; i < FGEnvironmentMgr::MAX_CLOUD_LAYERS; i++) {
 379         snprintf(s, 128, cl, i);
 380         strncat(s, "/coverage", 128);
 381         fgSetString(s, "clear");
 382
 383         snprintf(s, 128, cl, i);
 384         strncat(s, "/elevation-ft", 128);
 385         fgSetDouble(s, -9999);
 386
 387         snprintf(s, 128, cl, i);
 388         strncat(s, "/thickness-ft", 128);
 389         fgSetDouble(s, 0);
 390
 391         snprintf(s, 128, cl, i);
 392         strncat(s, "/span-m", 128);
 393         fgSetDouble(s, 40000.0);
 394     }
 395
 396     fgSetDouble("/environment/metar/rain-norm", m->getRain());
 397     fgSetDouble("/environment/metar/hail-norm", m->getHail());
 398     fgSetDouble("/environment/metar/snow-norm", m->getSnow());
 399     fgSetBool("/environment/metar/snow-cover", m->getSnowCover());
 400 }
 401
 402 void
 403 FGClouds::update_env_config ()
 404 {
 405     fgSetupWind( fgGetDouble("/environment/metar/base-wind-range-from"),
 406                  fgGetDouble("/environment/metar/base-wind-range-to"),
 407                  fgGetDouble("/environment/metar/base-wind-speed-kt"),
 408                  fgGetDouble("/environment/metar/gust-wind-speed-kt") );
 409
 410     fgDefaultWeatherValue( "visibility-m",
 411                            fgGetDouble("/environment/metar/min-visibility-m") );
 412 #if 0
 413     set_temp_at_altitude( fgGetDouble("/environment/metar/temperature-degc"),
 414                           station_elevation_ft );
 415     set_dewpoint_at_altitude( fgGetDouble("/environment/metar/dewpoint-degc"),
 416                               station_elevation_ft );
 417 #endif
 418     fgDefaultWeatherValue( "pressure-sea-level-inhg",
 419                            fgGetDouble("/environment/metar/pressure-inhg") );
 420 }
 421
 422
 423 void FGClouds::setLayer( int iLayer, float alt_ft, const string& coverage, const string& layer_type ) {
 424         double coverage_norm = 0.0;
 425         if( coverage == "few" )
 426                 coverage_norm = 2.0/8.0;        // <1-2
 427         else if( coverage == "scattered" )
 428                 coverage_norm = 4.0/8.0;        // 3-4
 429         else if( coverage == "broken" )
 430                 coverage_norm = 6.0/8.0;        // 5-7
 431         else if( coverage == "overcast" )
 432                 coverage_norm = 8.0/8.0;        // 8
 433
 434         buildLayer(iLayer, layer_type, station_elevation_ft + alt_ft * SG_FEET_TO_METER, coverage_norm);
 435 }
 436
 437 void FGClouds::buildScenario( const string& scenario ) {
 438         string fakeMetar="";
 439         string station = fgGetString("/environment/metar/station-id", "XXXX");
 440
 441         // fetch station elevation if exists
 442     if( station == "XXXX" )
 443         station_elevation_ft = fgGetDouble("/position/ground-elev-m", 0.0);
 444     else {
 445         const FGAirport* a = globals->get_airports()->search( station );
 446         station_elevation_ft = (a ? a->getElevation() : 0.0);
 447     }
 448
 449         for(int iLayer = 0 ; iLayer < thesky->get_cloud_layer_count(); iLayer++) {
 450             thesky->get_cloud_layer(iLayer)
 451                 ->setCoverage(SGCloudLayer::SG_CLOUD_CLEAR);
 452             thesky->get_cloud_layer(iLayer)->get_layer3D()->clear();
 453         }
 454
 455         station += " 011000Z ";
 456         if( scenario == "Fair weather" ) {
 457                 fakeMetar = "15003KT 12SM SCT033 FEW200 20/08 Q1015 NOSIG";
 458                 setLayer(0, 3300.0, "scattered", "cu");
 459         } else if( scenario == "Thunderstorm" ) {
 460                 fakeMetar = "15012KT 08SM TSRA SCT040 BKN070 20/12 Q0995";
 461                 setLayer(0, 4000.0, "scattered", "cb");
 462                 setLayer(1, 7000.0, "scattered", "ns");
 463         } else
 464                 return;
 465         FGMetar *m = new FGMetar( station + fakeMetar );
 466         update_metar_properties( m );
 467         update_env_config();
 468         // propagate aloft tables
 469         _controller->reinit();
 470
 471         fgSetString("/environment/metar/last-metar", m->getData());
 472         // TODO:desactivate real metar updates
 473         if( scenario == "Fair weather" ) {
 474                 fgSetString("/environment/clouds/layer[1]/coverage", "cirrus");
 475         }
 476 }
 477
 478
 479 void FGClouds::build(void) {
 480         string scenario = fgGetString("/environment/weather-scenario", "METAR");
 481
 482     if( scenario == last_scenario)
 483         return;
 484     if( last_scenario == "none" ) {
 485         // save clouds and weather conditions
 486         SGPropertyNode *param = fgGetNode("/environment/config", true);
 487         copyProperties( param, last_env_config );
 488         param = fgGetNode("/environment/clouds", true);
 489         copyProperties( param, last_env_clouds );
 490     }
 491         if( scenario == "METAR" ) {
 492                 string realMetar = fgGetString("/environment/metar/real-metar", "");
 493                 if( realMetar != "" ) {
 494                         fgSetString("/environment/metar/last-metar", realMetar.c_str());
 495                         FGMetar *m = new FGMetar( realMetar );
 496                         update_metar_properties( m );
 497                         update_env_config();
 498                         // propagate aloft tables
 499                         _controller->reinit();
 500                 }
 501                 buildMETAR();
 502         }
 503     else if( scenario == "none" ) {
 504         // restore clouds and weather conditions
 505         SGPropertyNode *param = fgGetNode("/environment/config", true);
 506         copyProperties( last_env_config, param );
 507         param = fgGetNode("/environment/clouds", true);
 508         copyProperties( last_env_clouds, param );
 509         fgSetDouble("/environment/metar/rain-norm", 0.0);
 510         fgSetDouble("/environment/metar/snow-norm", 0.0);
 511 //          update_env_config();
 512             // propagate aloft tables
 513             _controller->reinit();
 514                 buildMETAR();
 515     }
 516         else
 517                 buildScenario( scenario );
 518     last_scenario = scenario;
 519
 520         // ...
 521         if( snd_lightning == NULL )
 522                 init();
 523 }