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         rebuild_required(true),
  55     last_scenario( "none" ),
  56     last_env_config( new SGPropertyNode() ),
  57     last_env_clouds( new SGPropertyNode() )
  58 {
  59         update_event = 0;
  60         fgSetString("/environment/weather-scenario", last_scenario.c_str());
  61 }
  62 FGClouds::~FGClouds() {
  63 }
  64
  65 int FGClouds::get_update_event(void) const {
  66         return update_event;
  67 }
  68 void FGClouds::set_update_event(int count) {
  69         update_event = count;
  70         build();
  71 }
  72
  73 void FGClouds::init(void) {
  74         if( snd_lightning == NULL ) {
  75                 snd_lightning = new SGSoundSample(globals->get_fg_root().c_str(), "Sounds/thunder.wav");
  76                 snd_lightning->set_max_dist(7000.0f);
  77                 snd_lightning->set_reference_dist(3000.0f);
  78                 SGSoundMgr *soundMgr = globals->get_soundmgr();
  79                 soundMgr->add( snd_lightning, "thunder" );
  80                 sgEnviro.set_soundMgr( soundMgr );
  81         }
  82
  83         rebuild_required = true;
  84 }
  85
  86 void FGClouds::buildCloud(SGPropertyNode *cloud_def_root, SGPropertyNode  *box_def_root, const string& name, sgVec3 pos, SGCloudField *layer) {
  87         SGPropertyNode *box_def=NULL;
  88         SGPropertyNode *cld_def=NULL;
  89
  90         SGPath texture_root = globals->get_fg_root();
  91         texture_root.append("Textures");
  92         texture_root.append("Sky");
  93
  94         box_def = box_def_root->getChild(name.c_str());
  95
  96         string base_name = name.substr(0,2);
  97         if( !box_def ) {
  98                 if( name[2] == '-' ) {
  99                         box_def = box_def_root->getChild(base_name.c_str());
 100                 }
 101                 if( !box_def )
 102                         return;
 103         }
 104
 105         for(int i = 0; i < box_def->nChildren() ; i++) {
 106                 SGPropertyNode *abox = box_def->getChild(i);
 107                 if( strcmp(abox->getName(), "box") == 0) {
 108                         double x = abox->getDoubleValue("x") + pos[0];
 109                         double y = abox->getDoubleValue("y") + pos[1];
 110                         double z = abox->getDoubleValue("z") + pos[2];
 111                         SGVec3f newpos = SGVec3f(x, z, y);
 112
 113                         string type = abox->getStringValue("type", "cu-small");
 114
 115                         cld_def = cloud_def_root->getChild(type.c_str());
 116                         if ( !cld_def ) return;
 117
 118                         double min_width = cld_def->getDoubleValue("min-cloud-width-m", 500.0);
 119                         double max_width = cld_def->getDoubleValue("max-cloud-width-m", 1000.0);
 120                         double min_height = cld_def->getDoubleValue("min-cloud-height-m", min_width);
 121                         double max_height = cld_def->getDoubleValue("max-cloud-height-m", max_width);
 122                         double min_sprite_width = cld_def->getDoubleValue("min-sprite-width-m", 200.0);
 123                         double max_sprite_width = cld_def->getDoubleValue("max-sprite-width-m", min_sprite_width);
 124                         double min_sprite_height = cld_def->getDoubleValue("min-sprite-height-m", min_sprite_width);
 125                         double max_sprite_height = cld_def->getDoubleValue("max-sprite-height-m", max_sprite_width);
 126                         int num_sprites = cld_def->getIntValue("num-sprites", 20);
 127                         int num_textures_x = cld_def->getIntValue("num-textures-x", 1);
 128                         int num_textures_y = cld_def->getIntValue("num-textures-y", 1);
 129                         double bottom_shade = cld_def->getDoubleValue("bottom-shade", 1.0);
 130                         string texture = cld_def->getStringValue("texture", "cl_cumulus.rgb");
 131
 132                         SGNewCloud *cld =
 133                                 new SGNewCloud(texture_root,
 134                                                texture,
 135                                                min_width,
 136                                                max_width,
 137                                                min_height,
 138                                                max_height,
 139                                                min_sprite_width,
 140                                                max_sprite_width,
 141                                                min_sprite_height,
 142                                                max_sprite_height,
 143                                                bottom_shade,
 144                                                num_sprites,
 145                                                num_textures_x,
 146                                                num_textures_y);
 147                         layer->addCloud(newpos, cld);
 148                 }
 149         }
 150 }
 151
 152 void FGClouds::buildLayer(int iLayer, const string& name, double alt, double coverage) {
 153         struct {
 154                 string name;
 155                 double count;
 156         } tCloudVariety[20];
 157         int CloudVarietyCount = 0;
 158         double totalCount = 0.0;
 159
 160         if (! clouds_3d_enabled) return;
 161
 162         SGPropertyNode *cloud_def_root = fgGetNode("/environment/cloudlayers/clouds", false);
 163         SGPropertyNode *box_def_root   = fgGetNode("/environment/cloudlayers/boxes", false);
 164         SGPropertyNode *layer_def_root = fgGetNode("/environment/cloudlayers/layers", false);
 165         SGCloudField *layer = thesky->get_cloud_layer(iLayer)->get_layer3D();
 166
 167         layer->clear();
 168         // when we don't generate clouds the layer is rendered in 2D
 169         if( coverage == 0.0 )
 170                 return;
 171         if( layer_def_root == NULL || cloud_def_root == NULL || box_def_root == NULL)
 172                 return;
 173
 174         SGPropertyNode *layer_def=NULL;
 175
 176         layer_def = layer_def_root->getChild(name.c_str());
 177         if( !layer_def ) {
 178                 if( name[2] == '-' ) {
 179                         string base_name = name.substr(0,2);
 180                         layer_def = layer_def_root->getChild(base_name.c_str());
 181                 }
 182                 if( !layer_def )
 183                         return;
 184         }
 185
 186         double grid_x_size = layer_def->getDoubleValue("grid-x-size", 1000.0);
 187         double grid_y_size = layer_def->getDoubleValue("grid-y-size", 1000.0);
 188         double grid_x_rand = layer_def->getDoubleValue("grid-x-rand", grid_x_size);
 189         double grid_y_rand = layer_def->getDoubleValue("grid-y-rand", grid_y_size);
 190         double grid_z_rand = layer_def->getDoubleValue("grid-z-rand");
 191
 192         for(int i = 0; i < layer_def->nChildren() ; i++) {
 193                 SGPropertyNode *acloud = layer_def->getChild(i);
 194                 if( strcmp(acloud->getName(), "cloud") == 0) {
 195                         string cloud_name = acloud->getStringValue("name");
 196                         tCloudVariety[CloudVarietyCount].name = cloud_name;
 197                         double count = acloud->getDoubleValue("count", 1.0);
 198                         tCloudVariety[CloudVarietyCount].count = count;
 199                         int variety = 0;
 200                         cloud_name = cloud_name + "-%d";
 201                         char variety_name[50];
 202                         do {
 203                                 variety++;
 204                                 snprintf(variety_name, sizeof(variety_name), cloud_name.c_str(), variety);
 205                         } while( box_def_root->getChild(variety_name, 0, false) );
 206
 207                         totalCount += count;
 208                         if( CloudVarietyCount < 20 )
 209                                 CloudVarietyCount++;
 210                 }
 211         }
 212         totalCount = 1.0 / totalCount;
 213         double currCoverage = 0.0;
 214
 215         for(double px = 0.0; px < SGCloudField::fieldSize; px += grid_x_size) {
 216                 for(double py = 0.0; py < SGCloudField::fieldSize; py += grid_y_size) {
 217                         double x = px + grid_x_rand * (sg_random() - 0.5) - (SGCloudField::fieldSize / 2.0);
 218                         double y = py + grid_y_rand * (sg_random() - 0.5) - (SGCloudField::fieldSize / 2.0);
 219                         double z = alt + grid_z_rand * (sg_random() - 0.5);
 220                         double choice = sg_random();
 221                         currCoverage += coverage;
 222                         if( currCoverage < 1.0 )
 223                                 continue;
 224                         currCoverage -= 1.0;
 225
 226                         for(int i = 0; i < CloudVarietyCount ; i ++) {
 227                                 choice -= tCloudVariety[i].count * totalCount;
 228                                 if( choice <= 0.0 ) {
 229                                         sgVec3 pos={x,z,y};
 230
 231                                         buildCloud(cloud_def_root, box_def_root, tCloudVariety[i].name, pos, layer);
 232                                         break;
 233                                 }
 234                         }
 235                 }
 236         }
 237
 238         // Now we've built any clouds, enable them
 239         thesky->get_cloud_layer(iLayer)->set_enable3dClouds(clouds_3d_enabled);
 240 }
 241
 242 // TODO:call this after real metar updates
 243 void FGClouds::buildMETAR(void) {
 244         SGPropertyNode *metar_root = fgGetNode("/environment", true);
 245
 246         double wind_speed_kt     = metar_root->getDoubleValue("wind-speed-kt");
 247         double temperature_degc  = metar_root->getDoubleValue("temperature-sea-level-degc");
 248         double dewpoint_degc     = metar_root->getDoubleValue("dewpoint-sea-level-degc");
 249         double pressure_mb              = metar_root->getDoubleValue("pressure-sea-level-inhg") * SG_INHG_TO_PA / 100.0;
 250
 251         double dewp = pow(10.0, 7.5 * dewpoint_degc / (237.7 + dewpoint_degc));
 252         double temp = pow(10.0, 7.5 * temperature_degc / (237.7 + temperature_degc));
 253         double rel_humidity = dewp * 100 / temp;
 254
 255         // formule d'Epsy, base d'un cumulus
 256         double cumulus_base = 122.0 * (temperature_degc - dewpoint_degc);
 257         double stratus_base = 100.0 * (100.0 - rel_humidity) * SG_FEET_TO_METER;
 258
 259         bool cu_seen = false;
 260
 261         for(int iLayer = 0 ; iLayer < thesky->get_cloud_layer_count(); iLayer++) {
 262                 SGPropertyNode *cloud_root = fgGetNode("/environment/clouds/layer", iLayer, true);
 263
 264                 double alt_ft = cloud_root->getDoubleValue("elevation-ft");
 265                 double alt_m = alt_ft * SG_FEET_TO_METER;
 266                 string coverage = cloud_root->getStringValue("coverage");
 267                 double coverage_norm = 0.0;
 268                 if( coverage == "few" )
 269                         coverage_norm = 2.0/8.0;        // <1-2
 270                 else if( coverage == "scattered" )
 271                         coverage_norm = 4.0/8.0;        // 3-4
 272                 else if( coverage == "broken" )
 273                         coverage_norm = 6.0/8.0;        // 5-7
 274                 else if( coverage == "overcast" )
 275                         coverage_norm = 8.0/8.0;        // 8
 276
 277                 string layer_type = "nn";
 278                 if( coverage == "cirrus" ) {
 279                         layer_type = "ci";
 280                 } else if( alt_ft > 16500 ) {
 281 //                      layer_type = "ci|cs|cc";
 282                         layer_type = "ci";
 283                 } else if( alt_ft > 6500 ) {
 284 //                      layer_type = "as|ac|ns";
 285                         layer_type = "ac";
 286                         if( pressure_mb < 1005.0 && coverage_norm >= 5.5 )
 287                                 layer_type = "ns";
 288                 } else {
 289 //                      layer_type = "st|cu|cb|sc";
 290                         // +/- 20% from stratus probable base
 291                         if( stratus_base * 0.80 < alt_m && stratus_base * 1.40 > alt_m )
 292                                 layer_type = "st";
 293                         // +/- 20% from cumulus probable base
 294                         else if( cumulus_base * 0.80 < alt_m && cumulus_base * 1.20 > alt_m )
 295                                 layer_type = "cu";
 296                         else {
 297                                 // above formulae is far from perfect
 298                                 if ( alt_ft < 2000 )
 299                                         layer_type = "st";
 300                                 else if( alt_ft < 4500 )
 301                                         layer_type = "cu";
 302                                 else
 303                                         layer_type = "sc";
 304                         }
 305                 }
 306
 307                 buildLayer(iLayer, layer_type, alt_m, coverage_norm);
 308         }
 309 }
 310
 311 // copy from FGMetarEnvironmentCtrl until better
 312 void
 313 FGClouds::update_metar_properties( const FGMetar *m )
 314 {
 315     int i;
 316     double d;
 317     char s[128];
 318
 319     fgSetString("/environment/metar/station-id", m->getId());
 320     fgSetDouble("/environment/metar/min-visibility-m",
 321                 m->getMinVisibility().getVisibility_m() );
 322     fgSetDouble("/environment/metar/max-visibility-m",
 323                 m->getMaxVisibility().getVisibility_m() );
 324
 325     const SGMetarVisibility *dirvis = m->getDirVisibility();
 326     for (i = 0; i < 8; i++, dirvis++) {
 327         const char *min = "/environment/metar/visibility[%d]/min-m";
 328         const char *max = "/environment/metar/visibility[%d]/max-m";
 329
 330         d = dirvis->getVisibility_m();
 331
 332         snprintf(s, 128, min, i);
 333         fgSetDouble(s, d);
 334         snprintf(s, 128, max, i);
 335         fgSetDouble(s, d);
 336     }
 337
 338     fgSetInt("/environment/metar/base-wind-range-from",
 339              m->getWindRangeFrom() );
 340     fgSetInt("/environment/metar/base-wind-range-to",
 341              m->getWindRangeTo() );
 342     fgSetDouble("/environment/metar/base-wind-speed-kt",
 343                 m->getWindSpeed_kt() );
 344     fgSetDouble("/environment/metar/gust-wind-speed-kt",
 345                 m->getGustSpeed_kt() );
 346     fgSetDouble("/environment/metar/temperature-degc",
 347                 m->getTemperature_C() );
 348     fgSetDouble("/environment/metar/dewpoint-degc",
 349                 m->getDewpoint_C() );
 350     fgSetDouble("/environment/metar/rel-humidity-norm",
 351                 m->getRelHumidity() );
 352     fgSetDouble("/environment/metar/pressure-inhg",
 353                 m->getPressure_inHg() );
 354
 355     vector<SGMetarCloud> cv = m->getClouds();
 356     vector<SGMetarCloud>::const_iterator cloud;
 357
 358     const char *cl = "/environment/clouds/layer[%i]";
 359     for (i = 0, cloud = cv.begin(); cloud != cv.end(); cloud++, i++) {
 360         const char *coverage_string[5] =
 361             { "clear", "few", "scattered", "broken", "overcast" };
 362         const double thickness[5] = { 0, 65, 600,750, 1000};
 363         int q;
 364
 365         snprintf(s, 128, cl, i);
 366         strncat(s, "/coverage", 128);
 367         q = cloud->getCoverage();
 368         fgSetString(s, coverage_string[q] );
 369
 370         snprintf(s, 128, cl, i);
 371         strncat(s, "/elevation-ft", 128);
 372         fgSetDouble(s, cloud->getAltitude_ft() + station_elevation_ft);
 373
 374         snprintf(s, 128, cl, i);
 375         strncat(s, "/thickness-ft", 128);
 376         fgSetDouble(s, thickness[q]);
 377
 378         snprintf(s, 128, cl, i);
 379         strncat(s, "/span-m", 128);
 380         fgSetDouble(s, 40000.0);
 381     }
 382
 383     for (; i < FGEnvironmentMgr::MAX_CLOUD_LAYERS; i++) {
 384         snprintf(s, 128, cl, i);
 385         strncat(s, "/coverage", 128);
 386         fgSetString(s, "clear");
 387
 388         snprintf(s, 128, cl, i);
 389         strncat(s, "/elevation-ft", 128);
 390         fgSetDouble(s, -9999);
 391
 392         snprintf(s, 128, cl, i);
 393         strncat(s, "/thickness-ft", 128);
 394         fgSetDouble(s, 0);
 395
 396         snprintf(s, 128, cl, i);
 397         strncat(s, "/span-m", 128);
 398         fgSetDouble(s, 40000.0);
 399     }
 400
 401     fgSetDouble("/environment/metar/rain-norm", m->getRain());
 402     fgSetDouble("/environment/metar/hail-norm", m->getHail());
 403     fgSetDouble("/environment/metar/snow-norm", m->getSnow());
 404     fgSetBool("/environment/metar/snow-cover", m->getSnowCover());
 405 }
 406
 407 void
 408 FGClouds::update_env_config ()
 409 {
 410     fgSetupWind( fgGetDouble("/environment/metar/base-wind-range-from"),
 411                  fgGetDouble("/environment/metar/base-wind-range-to"),
 412                  fgGetDouble("/environment/metar/base-wind-speed-kt"),
 413                  fgGetDouble("/environment/metar/gust-wind-speed-kt") );
 414
 415     fgDefaultWeatherValue( "visibility-m",
 416                            fgGetDouble("/environment/metar/min-visibility-m") );
 417 #if 0
 418     set_temp_at_altitude( fgGetDouble("/environment/metar/temperature-degc"),
 419                           station_elevation_ft );
 420     set_dewpoint_at_altitude( fgGetDouble("/environment/metar/dewpoint-degc"),
 421                               station_elevation_ft );
 422 #endif
 423     fgDefaultWeatherValue( "pressure-sea-level-inhg",
 424                            fgGetDouble("/environment/metar/pressure-inhg") );
 425 }
 426
 427
 428 void FGClouds::setLayer( int iLayer, float alt_ft, const string& coverage, const string& layer_type ) {
 429         double coverage_norm = 0.0;
 430         if( coverage == "few" )
 431                 coverage_norm = 2.0/8.0;        // <1-2
 432         else if( coverage == "scattered" )
 433                 coverage_norm = 4.0/8.0;        // 3-4
 434         else if( coverage == "broken" )
 435                 coverage_norm = 6.0/8.0;        // 5-7
 436         else if( coverage == "overcast" )
 437                 coverage_norm = 8.0/8.0;        // 8
 438
 439         buildLayer(iLayer, layer_type, station_elevation_ft + alt_ft * SG_FEET_TO_METER, coverage_norm);
 440 }
 441
 442 void FGClouds::buildScenario( const string& scenario ) {
 443         string fakeMetar="";
 444         string station = fgGetString("/environment/metar/station-id", "XXXX");
 445
 446         // fetch station elevation if exists
 447     if( station == "XXXX" )
 448         station_elevation_ft = fgGetDouble("/position/ground-elev-m", 0.0);
 449     else {
 450         const FGAirport* a = globals->get_airports()->search( station );
 451         station_elevation_ft = (a ? a->getElevation() : 0.0);
 452     }
 453
 454         for(int iLayer = 0 ; iLayer < thesky->get_cloud_layer_count(); iLayer++) {
 455             thesky->get_cloud_layer(iLayer)
 456                 ->setCoverage(SGCloudLayer::SG_CLOUD_CLEAR);
 457             thesky->get_cloud_layer(iLayer)->get_layer3D()->clear();
 458         }
 459
 460         station += " 011000Z ";
 461         if( scenario == "Fair weather" ) {
 462                 fakeMetar = "15003KT 12SM SCT033 FEW200 20/08 Q1015 NOSIG";
 463                 setLayer(0, 3300.0, "scattered", "cu");
 464         } else if( scenario == "Thunderstorm" ) {
 465                 fakeMetar = "15012KT 08SM TSRA SCT040 BKN070 20/12 Q0995";
 466                 setLayer(0, 4000.0, "scattered", "cb");
 467                 setLayer(1, 7000.0, "scattered", "ns");
 468         } else
 469                 return;
 470         FGMetar *m = new FGMetar( station + fakeMetar );
 471         update_metar_properties( m );
 472         update_env_config();
 473         // propagate aloft tables
 474         _controller->reinit();
 475
 476         fgSetString("/environment/metar/last-metar", m->getData());
 477         // TODO:desactivate real metar updates
 478         if( scenario == "Fair weather" ) {
 479                 fgSetString("/environment/clouds/layer[1]/coverage", "cirrus");
 480         }
 481 }
 482
 483
 484 void FGClouds::build() {
 485         string scenario = fgGetString("/environment/weather-scenario", "METAR");
 486
 487         if(!rebuild_required && (scenario == last_scenario))
 488             return;
 489
 490
 491
 492         if( last_scenario == "none" ) {
 493         // save clouds and weather conditions
 494             SGPropertyNode *param = fgGetNode("/environment/config", true);
 495             copyProperties( param, last_env_config );
 496             param = fgGetNode("/environment/clouds", true);
 497             copyProperties( param, last_env_clouds );
 498         }
 499         if( scenario == "METAR" ) {
 500             string realMetar = fgGetString("/environment/metar/real-metar", "");
 501             if( realMetar != "" ) {
 502                 fgSetString("/environment/metar/last-metar", realMetar.c_str());
 503                 FGMetar *m = new FGMetar( realMetar );
 504                 update_metar_properties( m );
 505                 update_env_config();
 506                         // propagate aloft tables
 507                 _controller->reinit();
 508             }
 509             buildMETAR();
 510         }
 511         else if( scenario == "none" ) {
 512         // restore clouds and weather conditions
 513             SGPropertyNode *param = fgGetNode("/environment/config", true);
 514             copyProperties( last_env_config, param );
 515             param = fgGetNode("/environment/clouds", true);
 516             copyProperties( last_env_clouds, param );
 517             fgSetDouble("/environment/metar/rain-norm", 0.0);
 518             fgSetDouble("/environment/metar/snow-norm", 0.0);
 519 //          update_env_config();
 520             // propagate aloft tables
 521             _controller->reinit();
 522             buildMETAR();
 523         }
 524         else
 525             buildScenario( scenario );
 526
 527         last_scenario = scenario;
 528         rebuild_required = false;
 529
 530         // ...
 531         if( snd_lightning == NULL )
 532             init();
 533 }
 534
 535 void FGClouds::set_3dClouds(bool enable)
 536 {
 537     if (enable != clouds_3d_enabled)
 538     {
 539         clouds_3d_enabled = enable;
 540
 541         for(int iLayer = 0 ; iLayer < thesky->get_cloud_layer_count(); iLayer++) {
 542             thesky->get_cloud_layer(iLayer)->set_enable3dClouds(enable);
 543
 544             if (!enable) {
 545                 thesky->get_cloud_layer(iLayer)->get_layer3D()->clear();
 546             }
 547         }
 548
 549         if (enable)
 550         {
 551             rebuild_required = true;
 552             build();
 553         }
 554     }
 555 }
 556
 557 bool FGClouds::get_3dClouds() const {
 558     return clouds_3d_enabled;
 559 }
 560