From: torsten Date: Wed, 24 Mar 2010 14:25:36 +0000 (+0000) Subject: Bugfix: X-Git-Url: https://git.mxchange.org/?a=commitdiff_plain;h=26a72a9ee23ce49ec6ae9f7530d628d3c85b58b0;p=flightgear.git Bugfix: - METAR changes caused strong aircraft movements if the station temperature or field elevation changed. Temperature and dewpoint are now also slowly interpolated to reach the new value. - Probably unnoticed bug: calculation of the interpolation speed was wrong. - some minor code-cleanup --- diff --git a/src/Environment/environment_ctrl.cxx b/src/Environment/environment_ctrl.cxx index 0aa3572f6..6efcbde3e 100644 --- a/src/Environment/environment_ctrl.cxx +++ b/src/Environment/environment_ctrl.cxx @@ -273,11 +273,13 @@ FGMetarCtrl::FGMetarCtrl( SGSubsystem * environmentCtrl ) metar_valid(false), setup_winds_aloft(true), wind_interpolation_required(true), + metar_sealevel_temperature(15.0), + metar_sealevel_dewpoint(5.0), // Interpolation constant definitions. - EnvironmentUpdatePeriodSec( 0.2 ), MaxWindChangeKtsSec( 0.2 ), MaxVisChangePercentSec( 0.05 ), - MaxPressureChangeInHgSec( 0.0033 ), + MaxPressureChangeInHgSec( 0.0005 ), // approx 1hpa/min + MaxTemperatureChangeDegcSec(10.0/60.0), // approx 10degc/min MaxCloudAltitudeChangeFtSec( 20.0 ), MaxCloudThicknessChangeFtSec( 50.0 ), MaxCloudInterpolationHeightFt( 5000.0 ), @@ -311,10 +313,12 @@ FGMetarCtrl::FGMetarCtrl( SGSubsystem * environmentCtrl ) latitude_n = fgGetNode( "/position/latitude-deg", true ); environment_clouds_n = fgGetNode("/environment/clouds"); - boundary_wind_speed_n = fgGetNode("/environment/config/boundary/entry/wind-speed-kt"); - boundary_wind_from_heading_n = fgGetNode("/environment/config/boundary/entry/wind-from-heading-deg"); - boundary_visibility_n = fgGetNode("/environment/config/boundary/entry/visibility-m"); - boundary_sea_level_pressure_n = fgGetNode("/environment/config/boundary/entry/pressure-sea-level-inhg"); + boundary_wind_speed_n = fgGetNode("/environment/config/boundary/entry/wind-speed-kt", true ); + boundary_wind_from_heading_n = fgGetNode("/environment/config/boundary/entry/wind-from-heading-deg", true ); + boundary_visibility_n = fgGetNode("/environment/config/boundary/entry/visibility-m", true ); + boundary_sea_level_pressure_n = fgGetNode("/environment/config/boundary/entry/pressure-sea-level-inhg", true ); + boundary_sea_level_temperature_n = fgGetNode("/environment/config/boundary/entry/temperature-sea-level-degc", true ); + boundary_sea_level_dewpoint_n = fgGetNode("/environment/config/boundary/entry/dewpoint-sea-level-degc", true ); } FGMetarCtrl::~FGMetarCtrl () @@ -336,22 +340,26 @@ void FGMetarCtrl::unbind () } // use a "command" to set station temp at station elevation -static void set_temp_at_altitude( float temp_degc, float altitude_ft ) { +static void set_temp_at_altitude( double temp_degc, double altitude_ft ) { SGPropertyNode args; SGPropertyNode *node = args.getNode("temp-degc", 0, true); - node->setFloatValue( temp_degc ); + node->setDoubleValue( temp_degc ); node = args.getNode("altitude-ft", 0, true); - node->setFloatValue( altitude_ft ); - globals->get_commands()->execute("set-outside-air-temp-degc", &args); + node->setDoubleValue( altitude_ft ); + globals->get_commands()->execute( altitude_ft == 0.0 ? + "set-sea-level-air-temp-degc" : + "set-outside-air-temp-degc", &args); } -static void set_dewpoint_at_altitude( float dewpoint_degc, float altitude_ft ) { +static void set_dewpoint_at_altitude( double dewpoint_degc, double altitude_ft ) { SGPropertyNode args; SGPropertyNode *node = args.getNode("dewpoint-degc", 0, true); - node->setFloatValue( dewpoint_degc ); + node->setDoubleValue( dewpoint_degc ); node = args.getNode("altitude-ft", 0, true); - node->setFloatValue( altitude_ft ); - globals->get_commands()->execute("set-dewpoint-temp-degc", &args); + node->setDoubleValue( altitude_ft ); + globals->get_commands()->execute( altitude_ft == 0.0 ? + "set-dewpoint-sea-level-air-temp-degc" : + "set-dewpoint-temp-degc", &args); } /* @@ -403,10 +411,8 @@ static void setupWind( bool setup_aloft, double dir, double speed, double gust ) setupWindBranch( "aloft", dir, speed, gust ); } -double FGMetarCtrl::interpolate_val(double currentval, double requiredval, double dt) +double FGMetarCtrl::interpolate_val(double currentval, double requiredval, double dval ) { - double dval = EnvironmentUpdatePeriodSec * dt; - if (fabs(currentval - requiredval) < dval) return requiredval; if (currentval < requiredval) return (currentval + dval); if (currentval > requiredval) return (currentval - dval); @@ -448,13 +454,12 @@ static inline double convert_to_180( double d ) static double reducePressureSl(double metarPressure, double fieldHt, double fieldTemp) { - double elev = fieldHt * SG_FEET_TO_METER; - double fieldPressure - = FGAtmo::fieldPressure(elev, metarPressure * atmodel::inHg); - double slPressure = P_layer(0, elev, fieldPressure, - fieldTemp + atmodel::freezing, - atmodel::ISA::lam0); - return slPressure / atmodel::inHg; + double elev = fieldHt * SG_FEET_TO_METER; + double fieldPressure + = FGAtmo::fieldPressure(elev, metarPressure * atmodel::inHg); + double slPressure = P_layer(0, elev, fieldPressure, + fieldTemp + atmodel::freezing, atmodel::ISA::lam0); + return slPressure / atmodel::inHg; } void @@ -468,7 +473,7 @@ FGMetarCtrl::update(double dt) bool reinit_required = false; bool layer_rebuild_required = false; - double station_elevation_ft = station_elevation_n->getDoubleValue(); + double station_elevation_ft = station_elevation_n->getDoubleValue(); if (first_update) { double dir = base_wind_dir_n->getDoubleValue()+magnetic_variation_n->getDoubleValue(); @@ -479,11 +484,14 @@ FGMetarCtrl::update(double dt) double metarvis = min_visibility_n->getDoubleValue(); fgDefaultWeatherValue("visibility-m", metarvis); + set_temp_at_altitude(temperature_n->getDoubleValue(), station_elevation_ft); + set_dewpoint_at_altitude(dewpoint_n->getDoubleValue(), station_elevation_ft); + double metarpressure = pressure_n->getDoubleValue(); fgDefaultWeatherValue("pressure-sea-level-inhg", - reducePressureSl(metarpressure, - station_elevation_ft, - temperature_n->getDoubleValue())); + reducePressureSl(metarpressure, + station_elevation_ft, + temperature_n->getDoubleValue())); // We haven't already loaded a METAR, so apply it immediately. vector layers = clouds_n->getChildren("layer"); @@ -543,8 +551,8 @@ FGMetarCtrl::update(double dt) double maxdy = dy * MaxWindChangeKtsSec; // Interpolate each component separately. - current[0] = interpolate_val(current[0], metar[0], maxdx); - current[1] = interpolate_val(current[1], metar[1], maxdy); + current[0] = interpolate_val(current[0], metar[0], maxdx*dt); + current[1] = interpolate_val(current[1], metar[1], maxdy*dt); // Now convert back to polar coordinates. if ((fabs(current[0]) > 0.1) || (fabs(current[1]) > 0.1)) { @@ -615,7 +623,7 @@ FGMetarCtrl::update(double dt) double currentxval = log(1000.0 + vis); double metarxval = log(1000.0 + metarvis); - currentxval = interpolate_val(currentxval, metarxval, MaxVisChangePercentSec); + currentxval = interpolate_val(currentxval, metarxval, MaxVisChangePercentSec*dt); // Now convert back from an X-value to a straightforward visibility. vis = exp(currentxval) - 1000.0; @@ -625,15 +633,28 @@ FGMetarCtrl::update(double dt) double pressure = boundary_sea_level_pressure_n->getDoubleValue(); double metarpressure = pressure_n->getDoubleValue(); - double newpressure = reducePressureSl(metarpressure, - station_elevation_ft, - temperature_n->getDoubleValue()); + double newpressure = reducePressureSl(metarpressure, + station_elevation_ft, + temperature_n->getDoubleValue()); if( pressure != newpressure ) { - pressure = interpolate_val( pressure, newpressure, MaxPressureChangeInHgSec ); + pressure = interpolate_val( pressure, newpressure, MaxPressureChangeInHgSec*dt ); fgDefaultWeatherValue("pressure-sea-level-inhg", pressure); reinit_required = true; } + { + double temperature = boundary_sea_level_temperature_n->getDoubleValue(); + double dewpoint = boundary_sea_level_dewpoint_n->getDoubleValue(); + if( metar_sealevel_temperature != temperature ) { + temperature = interpolate_val( temperature, metar_sealevel_temperature, MaxTemperatureChangeDegcSec*dt ); + set_temp_at_altitude( temperature, 0.0 ); + } + if( metar_sealevel_dewpoint != dewpoint ) { + dewpoint = interpolate_val( dewpoint, metar_sealevel_dewpoint, MaxTemperatureChangeDegcSec*dt ); + set_dewpoint_at_altitude( dewpoint, 0.0 ); + } + } + // Set the cloud layers by interpolating over the METAR versions. vector layers = clouds_n->getChildren("layer"); vector::const_iterator layer; @@ -682,7 +703,7 @@ FGMetarCtrl::update(double dt) } else { // Interpolate the other values in the usual way if (current_alt != required_alt) { - current_alt = interpolate_val(current_alt, required_alt, MaxCloudAltitudeChangeFtSec); + current_alt = interpolate_val(current_alt, required_alt, MaxCloudAltitudeChangeFtSec*dt); target->setDoubleValue("elevation-ft", current_alt); } @@ -691,15 +712,12 @@ FGMetarCtrl::update(double dt) if (current_thickness != required_thickness) { current_thickness = interpolate_val(current_thickness, required_thickness, - MaxCloudThicknessChangeFtSec); + MaxCloudThicknessChangeFtSec*dt); thickness->setDoubleValue(current_thickness); } } } } - set_temp_at_altitude(temperature_n->getDoubleValue(), station_elevation_ft); - set_dewpoint_at_altitude(dewpoint_n->getDoubleValue(), station_elevation_ft); - //TODO: check if temperature/dewpoint have changed. This requires reinit. // Force an update of the 3D clouds if( layer_rebuild_required ) @@ -783,6 +801,15 @@ void FGMetarCtrl::set_metar( const char * metar_string ) station_elevation_n->setDoubleValue( station_elevation_ft ); + { // calculate sea level temperature and dewpoint + FGEnvironment dummy; // instantiate a dummy so we can leech a method + dummy.set_elevation_ft( station_elevation_ft ); + dummy.set_temperature_degc( temperature_n->getDoubleValue() ); + dummy.set_dewpoint_degc( dewpoint_n->getDoubleValue() ); + metar_sealevel_temperature = dummy.get_temperature_sea_level_degc(); + metar_sealevel_dewpoint = dummy.get_dewpoint_sea_level_degc(); + } + vector cv = m->getClouds(); vector::const_iterator cloud, cloud_end = cv.end(); diff --git a/src/Environment/environment_ctrl.hxx b/src/Environment/environment_ctrl.hxx index 0ecf8db8b..aec1442cb 100644 --- a/src/Environment/environment_ctrl.hxx +++ b/src/Environment/environment_ctrl.hxx @@ -152,12 +152,14 @@ private: bool first_update; bool wind_interpolation_required; string metar; + double metar_sealevel_temperature; + double metar_sealevel_dewpoint; double interpolate_prop(const char * currentname, const char * requiredname, double dvalue); double interpolate_val(double currentval, double requiredval, double dvalue); - const double EnvironmentUpdatePeriodSec; // Seconds between interpolations const double MaxWindChangeKtsSec; // Max wind change in kts/sec const double MaxVisChangePercentSec; // Max visibility change in %/sec const double MaxPressureChangeInHgSec; // Max pressure change in InHg/sec + const double MaxTemperatureChangeDegcSec; // Max temperature change in degc/s const double MaxCloudAltitudeChangeFtSec; // Max cloud altitude change in ft/s const double MaxCloudThicknessChangeFtSec; // Max cloud thickness change in ft/s const double MaxCloudInterpolationHeightFt; // Max distance from aircraft to @@ -200,6 +202,8 @@ private: SGPropertyNode_ptr boundary_wind_from_heading_n; SGPropertyNode_ptr boundary_visibility_n; SGPropertyNode_ptr boundary_sea_level_pressure_n; + SGPropertyNode_ptr boundary_sea_level_temperature_n; + SGPropertyNode_ptr boundary_sea_level_dewpoint_n; private: };