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Improved fog/mist/haze creation from METAR

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This commit is contained in:
Torsten Dreyer 2010-12-09 11:08:36 +01:00
parent 340bb58579
commit 87daa1290a
1 changed files with 36 additions and 16 deletions
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52
src/Environment/metarproperties.cxx
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@ -239,26 +239,46 @@ void MetarProperties::set_metar( const char * metar )
unsigned layerOffset = 0; // Oh, this is ugly!
bool setGroundCloudLayer = _rootNode->getBoolValue("set-ground-cloud-layer", false );
if( setGroundCloudLayer && isFG ) {
// make sure fog actually starts at ground and set it's bottom at a constant
if( setGroundCloudLayer ) {
// create a cloud layer #0 starting at the ground if its fog, mist or haze
// make sure layer actually starts at ground and set it's bottom at a constant
// value below the station's elevation
const double LAYER_BOTTOM_BELOW_STATION_ELEVATION=200;
// fog - create a cloud layer #0 starting at the ground
SGMetarCloud::Coverage coverage = SGMetarCloud::COVERAGE_NIL;
double thickness = 0;
double alpha = 1.0;
if( isFG ) { // fog
coverage = isBC ? SGMetarCloud::COVERAGE_SCATTERED : SGMetarCloud::COVERAGE_BROKEN;
thickness = isMI ?
30 + LAYER_BOTTOM_BELOW_STATION_ELEVATION : // shallow fog, 10m/30ft
500 + LAYER_BOTTOM_BELOW_STATION_ELEVATION; // fog, 150m/500ft
alpha = 1.0;
} else if( isBR ) { // mist
coverage = SGMetarCloud::COVERAGE_OVERCAST;
thickness = 2000 + LAYER_BOTTOM_BELOW_STATION_ELEVATION;
alpha = 0.8;
} else if( isHZ ) { // hase
coverage = SGMetarCloud::COVERAGE_OVERCAST;
thickness = 2000 + LAYER_BOTTOM_BELOW_STATION_ELEVATION;
alpha = 0.6;
}
// fog is "overcast" by default of "broken" for patches of fog
SGPropertyNode_ptr layerNode = cloudsNode->getChild(LAYER, 0, true );
SGMetarCloud::Coverage coverage = isBC ? SGMetarCloud::COVERAGE_SCATTERED : SGMetarCloud::COVERAGE_BROKEN;
layerNode->setDoubleValue( "coverage-type", SGCloudLayer::getCoverageType(coverage_string[coverage]) );
layerNode->setStringValue( "coverage", coverage_string[coverage] );
layerNode->setDoubleValue( "elevation-ft", _station_elevation - LAYER_BOTTOM_BELOW_STATION_ELEVATION );
layerNode->setDoubleValue( "thickness-ft", isMI ?
30 + LAYER_BOTTOM_BELOW_STATION_ELEVATION : // shallow fog, 10m/30ft
500 + LAYER_BOTTOM_BELOW_STATION_ELEVATION ); // fog, 150m/500ft
layerNode->setDoubleValue( "visibility-m", _min_visibility );
_min_visibility = _max_visibility = 20000.0; // assume good visibility above the fog
layerOffset = 1; // shudder
} else if( setGroundCloudLayer && isHZ ) {
}
if( coverage != SGMetarCloud::COVERAGE_NIL ) {
SGPropertyNode_ptr layerNode = cloudsNode->getChild(LAYER, 0, true );
layerNode->setDoubleValue( "coverage-type", SGCloudLayer::getCoverageType(coverage_string[coverage]) );
layerNode->setStringValue( "coverage", coverage_string[coverage] );
layerNode->setDoubleValue( "elevation-ft", _station_elevation - LAYER_BOTTOM_BELOW_STATION_ELEVATION );
layerNode->setDoubleValue( "thickness-ft", thickness );
layerNode->setDoubleValue( "visibility-m", _min_visibility );
layerNode->setDoubleValue( "alpha", alpha );
_min_visibility = _max_visibility = 20000.0; // assume good visibility above the fog
layerOffset = 1; // shudder
}
}
for( unsigned i = 0; i < 5-layerOffset; i++ ) {
SGPropertyNode_ptr layerNode = cloudsNode->getChild(LAYER, i+layerOffset, true );