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Calculate the day-light factor from the sun latitude and viewer latitude. Use it the calculate the mean temperatures. Fix a problem were non seasonal parameters where using seasonal interpolators.

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Erik Hofman 2020-11-14 13:43:53 +01:00
parent e450917611
commit 2b981b7ea7
2 changed files with 118 additions and 58 deletions
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167
src/Environment/climate.cxx
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@ -169,6 +169,7 @@ void FGClimate::update(double dt)
update_day_factor();
update_season_factor();
update_daylight();
_code = 0; // Ocean
osg::Vec4f color;
@ -228,6 +229,16 @@ void FGClimate::update(double dt)
}
}
// https://en.wikipedia.org/wiki/Sunrise_equation
void FGClimate::update_daylight()
{
double declination = _sun_latitude_deg*SGD_DEGREES_TO_RADIANS;
double latitude_deg = _positionLatitudeNode->getDoubleValue();
double latitude = latitude_deg*SGD_DEGREES_TO_RADIANS;
double hour_angle = acos(-tan(latitude) * tan(declination));
_day_light = hour_angle/SGD_PI;
}
// _day_noon returns 0.0 for night up to 1.0 for noon
void FGClimate::update_day_factor()
{
@ -272,10 +283,10 @@ void FGClimate::set_ocean()
double fact_lat = pow(fabs(latitude_deg)/90.0, 2.5);
double ifact_lat = 1.0 - fact_lat;
_set(_temperature_gl, season_even(ifact_lat, temp_pole, temp_equator));
_set(_temperature_gl, linear(ifact_lat, temp_pole, temp_equator));
double temp_mean_equator = 0.5*(temp_equator_day + temp_equator_night);
_set(_temperature_mean_gl, season_even(ifact_lat, temp_pole, temp_mean_equator));
double temp_mean_equator = 0.5*(temp_equator_night + temp_equator_day);
_set(_temperature_mean_gl, linear(ifact_lat, temp_pole, temp_mean_equator));
// relative humidity based on latitude
_set(_relative_humidity_gl, triangular(fabs(fact_lat-0.5), 70.0, 87.0));
@ -315,38 +326,38 @@ void FGClimate::set_tropical()
switch(_code)
{
case 1: // Af: equatorial, fully humid
temp_night = triangular(summer, 20.0, 22.5);
temp_day = triangular(summer, 29.5, 32.5);
temp_night = season_triangular(summer, 20.0, 22.5);
temp_day = season_triangular(summer, 29.5, 32.5);
precipitation = season_even(winter, 150.0, 280.0);
relative_humidity = triangular(humidity_fact, 75.0, 85.0);
relative_humidity = season_triangular(humidity_fact, 75.0, 85.0);
break;
case 2: // Am: equatorial, monsoonal
temp_night = triangular(summer, 17.5, 22.5, MONTH);
temp_day = triangular(summer, 27.5, 32.5, MONTH);
precipitation = linear(summer, 45.0, 340.0, MONTH);
relative_humidity = triangular(humidity_fact, 75.0, 85.0, MONTH);
temp_night = season_triangular(summer, 17.5, 22.5, MONTH);
temp_day = season_triangular(summer, 27.5, 32.5, MONTH);
precipitation = season_linear(summer, 45.0, 340.0, MONTH);
relative_humidity = season_triangular(humidity_fact, 75.0, 85.0, MONTH);
wind *= 2.0*_precipitation/320.0;
break;
case 3: // As: equatorial, summer dry
temp_night = season_long_high(summer, 15.0, 22.5, 1.5*MONTH);
temp_day = triangular(summer, 27.5, 35.0, MONTH);
temp_day = season_triangular(summer, 27.5, 35.0, MONTH);
precipitation = season_even(summer , 35.0, 150.0, 2.0*MONTH);
relative_humidity = triangular(humidity_fact, 60.0, 80.0, 2.0*MONTH);
relative_humidity = season_triangular(humidity_fact, 60.0, 80.0, 2.0*MONTH);
wind *= 2.0*_precipitation/350.0;
break;
case 4: // Aw: equatorial, winter dry
temp_night = season_long_high(summer, 15.0, 22.5, 1.5*MONTH);
temp_day = triangular(summer, 27.5, 35.0, 2.0*MONTH);
temp_day = season_triangular(summer, 27.5, 35.0, 2.0*MONTH);
precipitation = season_even(summer, 10.0, 230.0, 2.0*MONTH);
relative_humidity = triangular(humidity_fact, 60.0, 80.0, 2.0*MONTH);
relative_humidity = season_triangular(humidity_fact, 60.0, 80.0, 2.0*MONTH);
wind *= 2.0*_precipitation/230.0;
break;
default:
break;
}
_set(_temperature_gl, season_even(day, temp_night, temp_day));
_set(_temperature_mean_gl, 0.5*(temp_night + temp_day));
_set(_temperature_gl, linear(day, temp_night, temp_day));
_set(_temperature_mean_gl, linear(_day_light, temp_night, temp_day));
_set(_relative_humidity_gl, relative_humidity);
@ -376,9 +387,9 @@ void FGClimate::set_dry()
{
case 5: // BSh: arid, steppe, hot arid
temp_night = season_long_high(summer, 10.0, 22.0, MONTH);
temp_day = triangular(summer, 27.5, 35.0, 2.0*MONTH);
temp_day = season_triangular(summer, 27.5, 35.0, 2.0*MONTH);
precipitation = season_long_low(summer, 8.0, 117.0, 2.0*MONTH);
relative_humidity = triangular(humidity_fact, 20.0, 30.0, 2.0*MONTH);
relative_humidity = season_triangular(humidity_fact, 20.0, 30.0, 2.0*MONTH);
break;
case 6: // BSk: arid, steppe, cold arid
temp_night = season_even(summer, -14.0, 12.0, MONTH);
@ -395,15 +406,15 @@ void FGClimate::set_dry()
case 8: // BWk: arid, desert, cold arid
temp_night = season_even(summer, -15.0, 15.0, MONTH);
temp_day = season_even(summer, -2.0, 30.0, MONTH);
precipitation = linear(summer, 4.0, 14.0, MONTH);
relative_humidity = linear(humidity_fact, 45.0, 61.0, MONTH);
precipitation = season_linear(summer, 4.0, 14.0, MONTH);
relative_humidity = season_linear(humidity_fact, 45.0, 61.0, MONTH);
break;
default:
break;
}
_set(_temperature_gl, season_even(day, temp_night, temp_day));
_set(_temperature_mean_gl, 0.5*(temp_night + temp_day));
_set(_temperature_gl, linear(day, temp_night, temp_day));
_set(_temperature_mean_gl, linear(_day_light, temp_night, temp_day));
_set(_relative_humidity_gl, relative_humidity);
@ -448,20 +459,20 @@ void FGClimate::set_temperate()
case 11: // Cfc: warm temperature, fully humid, cool summer
temp_night = season_long_low(summer, -3.0, 8.0, 1.5*MONTH);
temp_day = season_long_low(summer, 2.0, 14.0, 1.5*MONTH);
precipitation = linear(winter, 90.0, 200.0);
precipitation = season_linear(winter, 90.0, 200.0);
relative_humidity = season_long_low(humidity_fact, 70.0, 85.0, 1.5*MONTH);
break;
case 12: // Csa: warm temperature, summer dry, hot summer
temp_night = season_even(summer, 2.0, 16.0, MONTH);
temp_day = season_even(summer, 12.0, 33.0, MONTH);
precipitation = linear(winter, 25.0, 70.0);
precipitation = season_linear(winter, 25.0, 70.0);
relative_humidity = season_even(humidity_fact, 58.0, 72.0, MONTH);
break;
case 13: // Csb: warm temperature, summer dry, warm summer
temp_night = linear(summer, -4.0, 10.0, 1.5*MONTH);
temp_day = linear(summer, 6.0, 27.0, 1.5*MONTH);
precipitation = linear(winter, 25.0, 120.0);
relative_humidity = linear(humidity_fact, 50.0, 72.0, 1.5*MONTH);
temp_night = season_linear(summer, -4.0, 10.0, 1.5*MONTH);
temp_day = season_linear(summer, 6.0, 27.0, 1.5*MONTH);
precipitation = season_linear(winter, 25.0, 120.0);
relative_humidity = season_linear(humidity_fact, 50.0, 72.0, 1.5*MONTH);
break;
case 14: // Csc: warm temperature, summer dry, cool summer
temp_night = season_even(summer, -4.0, 5.0, 0.5*MONTH);
@ -491,8 +502,8 @@ void FGClimate::set_temperate()
break;
}
_set(_temperature_gl, season_even(day, temp_night, temp_day));
_set(_temperature_mean_gl, 0.5*(temp_night + temp_day));
_set(_temperature_gl, linear(day, temp_night, temp_day));
_set(_temperature_mean_gl, linear(_day_light, temp_night, temp_day));
_set(_relative_humidity_gl, relative_humidity);
@ -523,19 +534,19 @@ void FGClimate::set_continetal()
case 18: // Dfa: snow, fully humid, hot summer
temp_night = season_even(summer, -15.0, 13.0, MONTH);
temp_day = season_even(summer, -5.0, 30.0, MONTH);
precipitation = linear(summer, 30.0, 70.0, MONTH);
precipitation = season_linear(summer, 30.0, 70.0, MONTH);
relative_humidity = season_even(humidity_fact, 68.0, 72.0);
break;
case 19: // Dfb: snow, fully humid, warm summer, warm summer
temp_night = season_even(summer, -17.5, 10.0, MONTH);
temp_day = season_even(summer, -7.5, 25.0, MONTH);
precipitation = linear(summer, 30.0, 70.0, MONTH);
precipitation = season_linear(summer, 30.0, 70.0, MONTH);
relative_humidity = season_even(humidity_fact, 69.0, 81.0, MONTH);
break;
case 20: // Dfc: snow, fully humid, cool summer, cool summer
temp_night = season_even(summer, -30.0, 4.0, MONTH);
temp_day = season_even(summer, -20.0, 15.0, MONTH);
precipitation = linear(summer, 22.0, 68.0, 1.5*MONTH);
precipitation = season_linear(summer, 22.0, 68.0, 1.5*MONTH);
relative_humidity = season_even(humidity_fact, 70.0, 88.0, MONTH);
break;
case 21: // Dfd: snow, fully humid, extremely continetal
@ -596,8 +607,8 @@ void FGClimate::set_continetal()
break;
}
_set(_temperature_gl, season_even(day, temp_night, temp_day));
_set(_temperature_mean_gl, 0.5*(temp_night + temp_day));
_set(_temperature_gl, linear(day, temp_night, temp_day));
_set(_temperature_mean_gl, linear(_day_light, temp_night, temp_day));
_set(_relative_humidity_gl, relative_humidity);
@ -627,7 +638,7 @@ void FGClimate::set_polar()
case 30: // EF: polar frost
temp_night = season_long_low(summer, -35.0, -6.0, MONTH);
temp_day = season_long_low(summer, -32.5, 0.0, MONTH);
precipitation = linear(summer, 50.0, 80.0, 2.5*MONTH);
precipitation = season_linear(summer, 50.0, 80.0, 2.5*MONTH);
relative_humidity = season_long_low(humidity_fact, 65.0, 75.0, MONTH);
break;
case 31: // ET: polar tundra
@ -640,8 +651,8 @@ void FGClimate::set_polar()
break;
}
_set(_temperature_gl, season_even(day, temp_night, temp_day));
_set(_temperature_mean_gl, 0.5*(temp_night + temp_day));
_set(_temperature_gl, linear(day, temp_night, temp_day));
_set(_temperature_mean_gl, linear(_day_light, temp_night, temp_day));
_set(_relative_humidity_gl, relative_humidity);
@ -702,13 +713,13 @@ void FGClimate::set_environment()
_set(_dust_cover, 0.0);
if (_temperature_mean_gl < 5.0) {
if (_temperature_mean_gl < -5.0) {
_set(_snow_thickness, wetness);
} else {
_set(_snow_thickness, 0.0);
}
if (_temperature_mean_gl > -5.0) {
if (_temperature_mean_gl > 0.0) {
_set(_wetness, pow(wetness, 2.0));
} else {
_set(_wetness, 0.0);
@ -718,6 +729,12 @@ void FGClimate::set_environment()
_set(_lichen_cover, 0.5*pow(wetness*cover, 1.5));
}
_rootNode->setDoubleValue("day-light-pct", _day_light*100.0);
_rootNode->setDoubleValue("day-noon-pct", _day_noon*100.0);
_rootNode->setDoubleValue("season-summer-pct", _season_summer*100.0);
_rootNode->setDoubleValue("seasons-year-pct", _seasons_year*100.0);
_rootNode->setDoubleValue("season-autumn-pct", ((_has_autumn && _is_autumn > 0.05) ? _season_transistional : 0.0));
if (_weather_update)
{
fgSetDouble("/environment/relative-humidity", _relative_humidity_gl);
@ -795,8 +812,28 @@ const std::string FGClimate::_description[MAX_CLIMATE_CLASSES] = {
"Polar tundra"
};
// interpolators
// val is the progress indicator between 0.0 and 1.0
double FGClimate::linear(double val, double min, double max, double offs)
double FGClimate::linear(double val, double min, double max)
{
double diff = max-min;
return min + val*diff;
}
// google: y=1-abs(-1+2*x)
// low season is around 0.0 and 1.0, high season around 0.5
double FGClimate::triangular(double val, double min, double max)
{
double diff = max-min;
val = 1.0 - fabs(-1.0 + 2.0*val);
return min + val*diff;
}
// season interpolators
// NOTE: uses _seasons_year so do not use for normal interpolation
double FGClimate::season_linear(double val, double min, double max, double offs)
{
double diff = max-min;
@ -809,7 +846,7 @@ double FGClimate::linear(double val, double min, double max, double offs)
// google: y=1-abs(-1+2*x)
// low season is around 0.0 and 1.0, high season around 0.5
double FGClimate::triangular(double val, double min, double max, double offs)
double FGClimate::season_triangular(double val, double min, double max, double offs)
{
double diff = max-min;
@ -898,39 +935,53 @@ void FGClimate::test()
printf("%5i", month+1);
}
printf("\nlinear:\t\t");
printf("\nseason_linear:\t\t");
for (int month=0; month<12; ++month) {
printf(" %-3.2f", linear(month/12.0, 0.0, 1.0, offs) );
double val = (month > 6) ? (12 - month)/6.0 : month/6.0;
_seasons_year = month/12.0;
printf(" %-3.2f", season_linear(val, 0.0, 1.0, offs) );
}
printf("\ntriangular:\t");
printf("\nseason_triangular:\t");
for (int month=0; month<12; ++month) {
printf(" %-3.2f", triangular(month/12.0, 0.0, 1.0, offs) );
double val = (month > 6) ? (12 - month)/6.0 : month/6.0;
_seasons_year = month/12.0;
printf(" %-3.2f", season_triangular(val, 0.0, 1.0, offs) );
}
printf("\neven:\t\t");
for (int month=0; month<12; ++month) {
printf(" %-3.2f", season_even(month/12.0, 0.0, 1.0, offs) );
double val = (month > 6) ? (12 - month)/6.0 : month/6.0;
_seasons_year = month/12.0;
printf(" %-3.2f", season_even(val, 0.0, 1.0, offs) );
}
printf("\nlong:\t\t");
for (int month=0; month<12; ++month) {
printf(" %-3.2f", season_long(month/12.0, 0.0, 1.0, offs) );
double val = (month > 6) ? (12 - month)/6.0 : month/6.0;
_seasons_year = month/12.0;
printf(" %-3.2f", season_long(val, 0.0, 1.0, offs) );
}
printf("\nlong low:\t");
for (int month=0; month<12; ++month) {
printf(" %-3.2f", season_long_low(month/12.0, 0.0, 1.0, offs) );
double val = (month > 6) ? (12 - month)/6.0 : month/6.0;
_seasons_year = month/12.0;
printf(" %-3.2f", season_long_low(val, 0.0, 1.0, offs) );
}
printf("\nlong high:\t");
for (int month=0; month<12; ++month) {
printf(" %-3.2f", season_long_high(month/12.0, 0.0, 1.0, offs) );
double val = (month > 6) ? (12 - month)/6.0 : month/6.0;
_seasons_year = month/12.0;
printf(" %-3.2f", season_long_high(val, 0.0, 1.0, offs) );
}
printf("\nmonsoonal:\t");
for (int month=0; month<12; ++month) {
printf(" %-3.2f", monsoonal(month/12.0, 0.0, 1.0, offs) );
double val = (month > 6) ? (12 - month)/6.0 : month/6.0;
_seasons_year = month/12.0;
printf(" %-3.2f", monsoonal(val, 0.0, 1.0, offs) );
}
printf("\n");
}
@ -958,17 +1009,21 @@ void FGClimate::report()
<< std::endl;
std::cout << " Description: " << _description[_code]
<< std::endl << std::endl;
std::cout << " Year (0.25 = spring .. 0.75 = autumn): " << _seasons_year
<< std::endl;
std::cout << " Season (0.0 = winter .. 1.0 = summer): " << _season_summer
std::cout << " Daylight: " << _day_light*100.0 << " %"
<< std::endl;
std::cout << " Daytime....(0.0 = night .. 1.0 = day): " << _day_noon
<< std::endl;
std::cout << " Sea level temperature: " << _temperature_sl << " deg. C."
std::cout << " Season (0.0 = winter .. 1.0 = summer): " << _season_summer
<< std::endl;
std::cout << " Year (0.25 = spring .. 0.75 = autumn): " << _seasons_year
<< std::endl << std::endl;
std::cout << " Ground temperature: " << _temperature_gl << " deg. C."
<< std::endl;
std::cout << " Mean temperature: " << _temperature_mean_gl
std::cout << " Sea level temperature: " << _temperature_sl << " deg. C."
<< std::endl;
std::cout << " Ground Mean temp.: " << _temperature_mean_gl
<< " deg. C." << std::endl;
std::cout << " Sea level mean temp.: " << _temperature_mean_sl
<< " deg. C." << std::endl;
std::cout << " Months precipitation: " << _precipitation << " mm"
<< std::endl;

9
src/Environment/climate.hxx
View file

@ -76,8 +76,11 @@ private:
}
// interpolate val (from 0.0 to 1.0) between min and max
double linear(double val, double min, double max, double offs = 0.0);
double triangular(double val, double min, double max, double offs = 0.0);
double linear(double val, double min, double max);
double triangular(double val, double min, double max);
double season_linear(double val, double min, double max, double offs = 0.0);
double season_triangular(double val, double min, double max, double offs = 0.0);
double season_even(double val, double min, double max, double offs = 0.0);
double season_long(double val, double min, double max, double offs = 0.0);
double season_long_low(double val, double min, double max, double offs = 0.0);
@ -92,6 +95,7 @@ private:
void set_polar();
void set_environment();
void update_daylight();
void update_day_factor();
void update_season_factor();
@ -119,6 +123,7 @@ private:
double _adj_longitude_deg = 0.0; // viewer lat adjusted for sun lon
double _day_noon = 1.0;
double _day_light = 1.0;
double _season_summer = 1.0;
double _season_transistional = 0.0;
double _seasons_year = 0.0;