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     snd_lightning(0),
  52     _controller(controller),
  53     station_elevation_ft(0.0),
  54     clouds_3d_enabled(false),
  55     last_scenario( "unset" ),
  56     last_env_config( new SGPropertyNode ),
  57     last_env_clouds( new SGPropertyNode )
  58 {
  59         update_event = 0;
  60 }
  61
  62 FGClouds::~FGClouds() {
  63 }
  64
  65 int FGClouds::get_update_event(void) const {
  66         return update_event;
  67 }
  68
  69 void FGClouds::set_update_event(int count) {
  70         update_event = count;
  71         buildCloudLayers();
  72 }
  73
  74 void FGClouds::init(void) {
  75         if( snd_lightning == NULL ) {
  76                 snd_lightning = new SGSoundSample(globals->get_fg_root().c_str(), "Sounds/thunder.wav");
  77                 snd_lightning->set_max_dist(7000.0f);
  78                 snd_lightning->set_reference_dist(3000.0f);
  79                 SGSoundMgr *soundMgr = globals->get_soundmgr();
  80                 soundMgr->add( snd_lightning, "thunder" );
  81                 sgEnviro.set_soundMgr( soundMgr );
  82         }
  83 }
  84
  85 void FGClouds::buildCloud(SGPropertyNode *cloud_def_root, SGPropertyNode  *box_def_root, const string& name, sgVec3 pos, SGCloudField *layer) {
  86         SGPropertyNode *box_def=NULL;
  87         SGPropertyNode *cld_def=NULL;
  88
  89         SGPath texture_root = globals->get_fg_root();
  90         texture_root.append("Textures");
  91         texture_root.append("Sky");
  92
  93         box_def = box_def_root->getChild(name.c_str());
  94
  95         string base_name = name.substr(0,2);
  96         if( !box_def ) {
  97                 if( name[2] == '-' ) {
  98                         box_def = box_def_root->getChild(base_name.c_str());
  99                 }
 100                 if( !box_def )
 101                         return;
 102         }
 103
 104         for(int i = 0; i < box_def->nChildren() ; i++) {
 105                 SGPropertyNode *abox = box_def->getChild(i);
 106                 if( strcmp(abox->getName(), "box") == 0) {
 107                         double x = abox->getDoubleValue("x") + pos[0];
 108                         double y = abox->getDoubleValue("y") + pos[1];
 109                         double z = abox->getDoubleValue("z") + pos[2];
 110                         SGVec3f newpos = SGVec3f(x, z, y);
 111
 112                         string type = abox->getStringValue("type", "cu-small");
 113
 114                         cld_def = cloud_def_root->getChild(type.c_str());
 115                         if ( !cld_def ) return;
 116
 117                         double min_width = cld_def->getDoubleValue("min-cloud-width-m", 500.0);
 118                         double max_width = cld_def->getDoubleValue("max-cloud-width-m", 1000.0);
 119                         double min_height = cld_def->getDoubleValue("min-cloud-height-m", min_width);
 120                         double max_height = cld_def->getDoubleValue("max-cloud-height-m", max_width);
 121                         double min_sprite_width = cld_def->getDoubleValue("min-sprite-width-m", 200.0);
 122                         double max_sprite_width = cld_def->getDoubleValue("max-sprite-width-m", min_sprite_width);
 123                         double min_sprite_height = cld_def->getDoubleValue("min-sprite-height-m", min_sprite_width);
 124                         double max_sprite_height = cld_def->getDoubleValue("max-sprite-height-m", max_sprite_width);
 125                         int num_sprites = cld_def->getIntValue("num-sprites", 20);
 126                         int num_textures_x = cld_def->getIntValue("num-textures-x", 1);
 127                         int num_textures_y = cld_def->getIntValue("num-textures-y", 1);
 128                         double bottom_shade = cld_def->getDoubleValue("bottom-shade", 1.0);
 129                         string texture = cld_def->getStringValue("texture", "cl_cumulus.rgb");
 130
 131                         SGNewCloud *cld =
 132                                 new SGNewCloud(type,
 133                                                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         SGPropertyNode *cloud_def_root = fgGetNode("/environment/cloudlayers/clouds", false);
 161         SGPropertyNode *box_def_root   = fgGetNode("/environment/cloudlayers/boxes", false);
 162         SGPropertyNode *layer_def_root = fgGetNode("/environment/cloudlayers/layers", false);
 163         SGCloudField *layer = thesky->get_cloud_layer(iLayer)->get_layer3D();
 164         layer->clear();
 165
 166         // If we don't have the required properties, then render the cloud in 2D
 167         if ((! clouds_3d_enabled) || coverage == 0.0 ||
 168             layer_def_root == NULL || cloud_def_root == NULL || box_def_root == NULL)
 169         {
 170                 thesky->get_cloud_layer(iLayer)->set_enable3dClouds(false);
 171                 return;
 172         }
 173
 174         // If we can't find a definition for this cloud type, then render the cloud in 2D
 175         SGPropertyNode *layer_def=NULL;
 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                 {
 184                         thesky->get_cloud_layer(iLayer)->set_enable3dClouds(false);
 185                         return;
 186                 }
 187         }
 188
 189         // At this point, we know we've got some 3D clouds to generate.
 190         thesky->get_cloud_layer(iLayer)->set_enable3dClouds(true);
 191
 192         double grid_x_size = layer_def->getDoubleValue("grid-x-size", 1000.0);
 193         double grid_y_size = layer_def->getDoubleValue("grid-y-size", 1000.0);
 194         double grid_x_rand = layer_def->getDoubleValue("grid-x-rand", grid_x_size);
 195         double grid_y_rand = layer_def->getDoubleValue("grid-y-rand", grid_y_size);
 196         double grid_z_rand = layer_def->getDoubleValue("grid-z-rand");
 197
 198         for(int i = 0; i < layer_def->nChildren() ; i++) {
 199                 SGPropertyNode *acloud = layer_def->getChild(i);
 200                 if( strcmp(acloud->getName(), "cloud") == 0) {
 201                         string cloud_name = acloud->getStringValue("name");
 202                         tCloudVariety[CloudVarietyCount].name = cloud_name;
 203                         double count = acloud->getDoubleValue("count", 1.0);
 204                         tCloudVariety[CloudVarietyCount].count = count;
 205                         int variety = 0;
 206                         cloud_name = cloud_name + "-%d";
 207                         char variety_name[50];
 208                         do {
 209                                 variety++;
 210                                 snprintf(variety_name, sizeof(variety_name), cloud_name.c_str(), variety);
 211                         } while( box_def_root->getChild(variety_name, 0, false) );
 212
 213                         totalCount += count;
 214                         if( CloudVarietyCount < 20 )
 215                                 CloudVarietyCount++;
 216                 }
 217         }
 218         totalCount = 1.0 / totalCount;
 219
 220         for(double px = 0.0; px < SGCloudField::fieldSize; px += grid_x_size) {
 221                 for(double py = 0.0; py < SGCloudField::fieldSize; py += grid_y_size) {
 222                         double x = px + grid_x_rand * (sg_random() - 0.5) - (SGCloudField::fieldSize / 2.0);
 223                         double y = py + grid_y_rand * (sg_random() - 0.5) - (SGCloudField::fieldSize / 2.0);
 224                         double z = grid_z_rand * (sg_random() - 0.5);
 225
 226                         if (sg_random() < coverage)
 227                         {
 228                             double choice = sg_random();
 229
 230                             for(int i = 0; i < CloudVarietyCount ; i ++) {
 231                                     choice -= tCloudVariety[i].count * totalCount;
 232                                     if( choice <= 0.0 ) {
 233                                             sgVec3 pos={x,z,y};
 234
 235                                             buildCloud(cloud_def_root,
 236                                                        box_def_root,
 237                                                        tCloudVariety[i].name,
 238                                                        pos,
 239                                                        layer);
 240                                             break;
 241                                     }
 242                             }
 243                         }
 244                 }
 245         }
 246
 247         // Now we've built any clouds, enable them and set the density (coverage)
 248         //layer->setCoverage(coverage);
 249         //layer->applyCoverage();
 250         thesky->get_cloud_layer(iLayer)->set_enable3dClouds(clouds_3d_enabled);
 251 }
 252
 253 void FGClouds::buildCloudLayers(void) {
 254         SGPropertyNode *metar_root = fgGetNode("/environment", true);
 255
 256         //double wind_speed_kt   = metar_root->getDoubleValue("wind-speed-kt");
 257         double temperature_degc  = metar_root->getDoubleValue("temperature-sea-level-degc");
 258         double dewpoint_degc     = metar_root->getDoubleValue("dewpoint-sea-level-degc");
 259         double pressure_mb              = metar_root->getDoubleValue("pressure-sea-level-inhg") * SG_INHG_TO_PA / 100.0;
 260
 261         double dewp = pow(10.0, 7.5 * dewpoint_degc / (237.7 + dewpoint_degc));
 262         double temp = pow(10.0, 7.5 * temperature_degc / (237.7 + temperature_degc));
 263         double rel_humidity = dewp * 100 / temp;
 264
 265         // formule d'Epsy, base d'un cumulus
 266         double cumulus_base = 122.0 * (temperature_degc - dewpoint_degc);
 267         double stratus_base = 100.0 * (100.0 - rel_humidity) * SG_FEET_TO_METER;
 268
 269         for(int iLayer = 0 ; iLayer < thesky->get_cloud_layer_count(); iLayer++) {
 270                 SGPropertyNode *cloud_root = fgGetNode("/environment/clouds/layer", iLayer, true);
 271
 272                 double alt_ft = cloud_root->getDoubleValue("elevation-ft");
 273                 double alt_m = alt_ft * SG_FEET_TO_METER;
 274                 string coverage = cloud_root->getStringValue("coverage");
 275
 276
 277                 double coverage_norm = 0.0;
 278                 if( coverage == "few" )
 279                         coverage_norm = 2.0/8.0;        // <1-2
 280                 else if( coverage == "scattered" )
 281                         coverage_norm = 4.0/8.0;        // 3-4
 282                 else if( coverage == "broken" )
 283                         coverage_norm = 6.0/8.0;        // 5-7
 284                 else if( coverage == "overcast" )
 285                         coverage_norm = 8.0/8.0;        // 8
 286
 287                 string layer_type = "nn";
 288                 if( coverage == "cirrus" ) {
 289                         layer_type = "ci";
 290                 } else if( alt_ft > 16500 ) {
 291 //                      layer_type = "ci|cs|cc";
 292                         layer_type = "ci";
 293                 } else if( alt_ft > 6500 ) {
 294 //                      layer_type = "as|ac|ns";
 295                         layer_type = "ac";
 296                         if( pressure_mb < 1005.0 && coverage_norm >= 0.5 )
 297                                 layer_type = "ns";
 298                 } else {
 299 //                      layer_type = "st|cu|cb|sc";
 300                         if( cumulus_base * 0.80 < alt_m && cumulus_base * 1.20 > alt_m ) {
 301                                 // +/- 20% from cumulus probable base
 302                                 layer_type = "cu";
 303                         } else if( stratus_base * 0.80 < alt_m && stratus_base * 1.40 > alt_m ) {
 304                                 // +/- 20% from stratus probable base
 305                                 layer_type = "st";
 306                         } else {
 307                                 // above formulae is far from perfect
 308                                 if ( alt_ft < 2000 )
 309                                         layer_type = "st";
 310                                 else if( alt_ft < 4500 )
 311                                         layer_type = "cu";
 312                                 else
 313                                         layer_type = "sc";
 314                         }
 315                 }
 316
 317                 buildLayer(iLayer, layer_type, alt_m, coverage_norm);
 318         }
 319 }
 320
 321 // copy from FGMetarEnvironmentCtrl until better
 322 void
 323 FGClouds::update_metar_properties( const FGMetar *m )
 324 {
 325     int i;
 326
 327     fgSetString("/environment/metar/station-id", m->getId());
 328     fgSetDouble("/environment/metar/min-visibility-m",
 329                 m->getMinVisibility().getVisibility_m() );
 330     fgSetDouble("/environment/metar/max-visibility-m",
 331                 m->getMaxVisibility().getVisibility_m() );
 332
 333     SGPropertyNode *metar = fgGetNode("/environment/metar", true);
 334     const SGMetarVisibility *dirvis = m->getDirVisibility();
 335
 336     for (i = 0; i < 8; i++, dirvis++) {
 337         SGPropertyNode *vis = metar->getChild("visibility", i, true);
 338         double v = dirvis->getVisibility_m();
 339
 340         vis->setDoubleValue("min-m", v);
 341         vis->setDoubleValue("max-m", v);
 342     }
 343
 344     fgSetInt("/environment/metar/base-wind-range-from",
 345              m->getWindRangeFrom() );
 346     fgSetInt("/environment/metar/base-wind-range-to",
 347              m->getWindRangeTo() );
 348     fgSetDouble("/environment/metar/base-wind-speed-kt",
 349                 m->getWindSpeed_kt() );
 350     fgSetDouble("/environment/metar/gust-wind-speed-kt",
 351                 m->getGustSpeed_kt() );
 352     fgSetDouble("/environment/metar/temperature-degc",
 353                 m->getTemperature_C() );
 354     fgSetDouble("/environment/metar/dewpoint-degc",
 355                 m->getDewpoint_C() );
 356     fgSetDouble("/environment/metar/rel-humidity-norm",
 357                 m->getRelHumidity() );
 358     fgSetDouble("/environment/metar/pressure-inhg",
 359                 m->getPressure_inHg() );
 360
 361     vector<SGMetarCloud> cv = m->getClouds();
 362     vector<SGMetarCloud>::const_iterator cloud, cloud_end = cv.end();
 363
 364     // Load into both the METAR and environment properties to stop interpolation
 365     SGPropertyNode *metar_clouds = fgGetNode("/environment/metar/clouds", true);
 366     SGPropertyNode *clouds = fgGetNode("/environment/clouds", true);
 367
 368     for (i = 0, cloud = cv.begin(); i < FGEnvironmentMgr::MAX_CLOUD_LAYERS; i++) {
 369         const char *coverage_string[5] = { "clear", "few", "scattered", "broken", "overcast" };
 370         const double thickness_value[5] = { 0, 65, 600, 750, 1000 };
 371
 372         const char *coverage = "clear";
 373         double elevation = -9999.0;
 374         double thickness = 0.0;
 375         const double span = 40000.0;
 376
 377         if (cloud != cloud_end) {
 378             int c = cloud->getCoverage();
 379             coverage = coverage_string[c];
 380             elevation = cloud->getAltitude_ft() + station_elevation_ft;
 381             thickness = thickness_value[c];
 382             ++cloud;
 383         }
 384
 385         SGPropertyNode *layer;
 386         layer = metar_clouds->getChild("layer", i, true);
 387         layer->setStringValue("coverage", coverage);
 388         layer->setDoubleValue("elevation-ft", elevation);
 389         layer->setDoubleValue("thickness-ft", thickness);
 390         layer->setDoubleValue("span-m", span);
 391
 392         layer = clouds->getChild("layer", i, true);
 393         layer->setStringValue("coverage", coverage);
 394         layer->setDoubleValue("elevation-ft", elevation);
 395         layer->setDoubleValue("thickness-ft", thickness);
 396         layer->setDoubleValue("span-m", span);
 397     }
 398
 399     fgSetDouble("/environment/metar/rain-norm", m->getRain());
 400     fgSetDouble("/environment/metar/hail-norm", m->getHail());
 401     fgSetDouble("/environment/metar/snow-norm", m->getSnow());
 402     fgSetBool("/environment/metar/snow-cover", m->getSnowCover());
 403 }
 404
 405 void
 406 FGClouds::update_env_config ()
 407 {
 408     fgSetupWind( fgGetDouble("/environment/metar/base-wind-range-from"),
 409                  fgGetDouble("/environment/metar/base-wind-range-to"),
 410                  fgGetDouble("/environment/metar/base-wind-speed-kt"),
 411                  fgGetDouble("/environment/metar/gust-wind-speed-kt") );
 412
 413     fgDefaultWeatherValue( "visibility-m",
 414                            fgGetDouble("/environment/metar/min-visibility-m") );
 415 #if 0
 416     set_temp_at_altitude( fgGetDouble("/environment/metar/temperature-degc"),
 417                           station_elevation_ft );
 418     set_dewpoint_at_altitude( fgGetDouble("/environment/metar/dewpoint-degc"),
 419                               station_elevation_ft );
 420 #endif
 421     fgDefaultWeatherValue( "pressure-sea-level-inhg",
 422                            fgGetDouble("/environment/metar/pressure-inhg") );
 423 }
 424
 425 void FGClouds::setLayer( int iLayer, float alt_ft, const string& coverage, const string& layer_type ) {
 426         double coverage_norm = 0.0;
 427         if( coverage == "few" )
 428                 coverage_norm = 2.0/8.0;        // <1-2
 429         else if( coverage == "scattered" )
 430                 coverage_norm = 4.0/8.0;        // 3-4
 431         else if( coverage == "broken" )
 432                 coverage_norm = 6.0/8.0;        // 5-7
 433         else if( coverage == "overcast" )
 434                 coverage_norm = 8.0/8.0;        // 8
 435
 436         buildLayer(iLayer, layer_type, station_elevation_ft + alt_ft * SG_FEET_TO_METER, coverage_norm);
 437 }
 438
 439 void FGClouds::buildScenario( const string& scenario ) {
 440         string fakeMetar="";
 441         string station = fgGetString("/environment/metar/station-id", "XXXX");
 442
 443         // fetch station elevation if exists
 444         if( station == "XXXX" )
 445             station_elevation_ft = fgGetDouble("/position/ground-elev-m", 0.0) * SG_METER_TO_FEET;
 446         else {
 447             const FGAirport* a = FGAirport::findByIdent(station);
 448             station_elevation_ft = (a ? a->getElevation() : 0.0);
 449         }
 450
 451         for(int iLayer = 0 ; iLayer < thesky->get_cloud_layer_count(); iLayer++) {
 452             thesky->get_cloud_layer(iLayer)
 453                 ->setCoverage(SGCloudLayer::SG_CLOUD_CLEAR);
 454             thesky->get_cloud_layer(iLayer)->get_layer3D()->clear();
 455         }
 456
 457         station += " 011000Z ";
 458         if( scenario == "Fair weather" ) {
 459                 fakeMetar = "15003KT 12SM SCT041 FEW200 20/08 Q1015 NOSIG";
 460                 //setLayer(0, 3300.0, "scattered", "cu");
 461         } else if( scenario == "Thunderstorm" ) {
 462                 fakeMetar = "15012KT 08SM TSRA SCT040 BKN070 20/12 Q0995";
 463                 setLayer(0, 4000.0, "scattered", "cb");
 464                 setLayer(1, 7000.0, "scattered", "ns");
 465         } else
 466                 return;
 467         FGMetar *m = new FGMetar( station + fakeMetar );
 468         update_metar_properties( m );
 469         update_env_config();
 470         // propagate aloft tables
 471         //_controller->reinit();
 472
 473         fgSetString("/environment/metar/last-metar", m->getData());
 474         // TODO:de-activate real metar updates
 475         if( scenario == "Fair weather" ) {
 476                 fgSetString("/environment/clouds/layer[1]/coverage", "cirrus");
 477         }
 478 }
 479
 480 void FGClouds::set_scenario(const char * sc) {
 481
 482         scenario = string(sc);
 483
 484 //        if(!rebuild_required && (scenario == last_scenario))
 485 //            return;
 486
 487         if( last_scenario == "none" ) {
 488         // save clouds and weather conditions
 489             SGPropertyNode *param = fgGetNode("/environment/config", true);
 490             copyProperties( param, last_env_config );
 491             param = fgGetNode("/environment/clouds", true);
 492             copyProperties( param, last_env_clouds );
 493         }
 494
 495         if( scenario == "METAR" ) {
 496             string realMetar = fgGetString("/environment/metar/real-metar", "");
 497
 498             if( realMetar != "" ) {
 499                 fgSetString("/environment/metar/last-metar", realMetar.c_str());
 500                 FGMetar *m = new FGMetar( realMetar );
 501                 update_metar_properties( m );
 502                 update_env_config();
 503                         // propagate aloft tables
 504                 _controller->reinit();
 505                 buildCloudLayers();
 506             }
 507         }
 508         else if( scenario == "none" ) {
 509         // restore clouds and weather conditions
 510             SGPropertyNode *param = fgGetNode("/environment/config", true);
 511             copyProperties( last_env_config, param );
 512             param = fgGetNode("/environment/clouds", true);
 513             copyProperties( last_env_clouds, param );
 514             fgSetDouble("/environment/metar/rain-norm", 0.0);
 515             fgSetDouble("/environment/metar/snow-norm", 0.0);
 516 //          update_env_config();
 517             // propagate aloft tables
 518             _controller->reinit();
 519             buildCloudLayers();
 520         }
 521         else {
 522             buildScenario( scenario );
 523             _controller->reinit();
 524             buildCloudLayers();
 525         }
 526
 527         last_scenario = scenario;
 528
 529         if( snd_lightning == NULL )
 530             init();
 531 }
 532
 533 const char * FGClouds::get_scenario(void) const
 534 {
 535     return scenario.c_str();
 536 }
 537
 538 void FGClouds::set_3dClouds(bool enable)
 539 {
 540     if (enable != clouds_3d_enabled) {
 541         clouds_3d_enabled = enable;
 542         buildCloudLayers();
 543     }
 544 }
 545
 546 bool FGClouds::get_3dClouds() const {
 547     return clouds_3d_enabled;
 548 }
 549