Useful observer orientation

data/ssystem_major.ini

@@ -1950,13 +1950,10 @@ color=0., 0., 0.
 halo=false
 hidden=true
 name=Earth Observer
-orbit_Inclination=90
-orbit_MeanLongitude=90
-orbit_Period=100000000000
-; 1AU to make earth orbit less distorted
-orbit_SemiMajorAxis=149600000
+tex_map=obs_earth.jpg
+; 800000 km is about twice Lunar orbit size
+orbit_SemiMajorAxis=800000
 parent=Earth
-rot_obliquity=0
 type=observer
 
 [mars_observer]
@@ -1965,13 +1962,10 @@ color = 0., 0., 0.
 halo = false
 hidden = true
 name = Mars Observer
-orbit_Inclination = 90
-orbit_MeanLongitude = 90
-orbit_Period = 70000000000
-; set to 1.5AU: Average light time as seen from earth.
-orbit_SemiMajorAxis = 224400000
+tex_map=obs_mars.jpg
+; 100000 km provides a good view of the moon orbits
+orbit_SemiMajorAxis = 100000
 parent = Mars
-rot_obliquity=0
 type = observer
 
 [jupiter_observer]
@@ -1980,13 +1974,10 @@ color = 0., 0., 0.
 halo = false
 hidden = true
 name = Jupiter Observer
-orbit_Inclination = 90
-orbit_MeanLongitude = 90
-orbit_Period = 70000000000
-; set to 5.2AU: Average light time as seen from earth.
-orbit_SemiMajorAxis = 777920000
+tex_map=obs_jupiter.jpg
+; 75 M km is about 1/2 AU, good to see all moon orbits
+orbit_SemiMajorAxis = 75000000
 parent = Jupiter
-rot_obliquity=0
 type = observer
 
 [saturn_observer]
@@ -1995,13 +1986,10 @@ color = 0., 0., 0.
 halo = false
 hidden = true
 name = Saturn Observer
-orbit_Inclination = 90
-orbit_MeanLongitude = 90
-orbit_Period = 70000000000
-; set to 9.6AU: Average light time as seen from earth.
-orbit_SemiMajorAxis = 1436160000
+tex_map=obs_saturn.jpg
+; 30 M km to see Phoebe's orbit
+orbit_SemiMajorAxis = 30000000
 parent = Saturn
-rot_obliquity=0
 type = observer
 
 [uranus_observer]
@@ -2010,13 +1998,10 @@ color = 0., 0., 0.
 halo = false
 hidden = true
 name = Uranus Observer
-orbit_Inclination = 90
-orbit_MeanLongitude = 90
-orbit_Period = 70000000000
-; set to 19.2AU: Average light time as seen from earth.
-orbit_SemiMajorAxis = 2872320000
+tex_map=obs_uranus.jpg
+; 1 M km to see moons' orbits
+orbit_SemiMajorAxis = 1000000
 parent = Uranus
-rot_obliquity=0
 type = observer
 
 [neptune_observer]
@@ -2025,29 +2010,20 @@ color = 0., 0., 0.
 halo = false
 hidden = true
 name = Neptune Observer
-orbit_Inclination = 90
-orbit_MeanLongitude = 90
-orbit_Period = 70000000000
-; set to 19.2AU: Average light time as seen from earth.
-orbit_SemiMajorAxis = 4498472000
+tex_map=obs_neptune.jpg
+; set to 1AU: Neptune has far-out moons!
+orbit_SemiMajorAxis = 150000000
 parent = Neptune
-rot_obliquity=0
 type = observer
 
 [solar_system_observer]
 albedo=0.
 color=0., 0., 0.
-; This is parented with the Sun! Therefore we should have comet_orbit, and semimajor axis in AU
+; This is parented with the Sun! Therefore semimajor axis in AU
 halo=false
 hidden=true
 name=Solar System Observer
-orbit_Inclination=90
-;orbit_MeanLongitude=90
-orbit_MeanAnomaly=90
-orbit_Epoch=2451545.0
-orbit_Period=70000000000
-;orbit_SemiMajorAxis=70 000 000 000
-; place distance around Neptune distance...
+tex_map=obs_sun.jpg
+; place distance in 30AU, around Neptune distance.
 orbit_SemiMajorAxis=30
-rot_obliquity=0
 type=observer

guide/app_ssystem_ini.tex

@@ -273,49 +273,38 @@ \subsubsection{Observers}
 \label{sec:ssystem.ini:SolarSystemObserver}
 
 The Solar System Observer has
-been provided as a neutral view location high above the North pole of
-the Solar System. It has been configured like this:
+been provided in earlier versions as a neutral view location high above the North pole of
+the Solar System. Meanwhile \newFeature{0.19.2} the location can be changed by keyboard interaction. See section \ref{sec:gui:location:observers}.
 \begin{configfile}
 [solar_system_observer]
 name=Solar System Observer
 parent=Sun
 halo=false
 hidden=true
-coord_func=ell_orbit
-orbit_Inclination=90
-orbit_MeanLongitude=90
-orbit_Period=70000000000
-orbit_SemiMajorAxis=70000000000
-rot_obliquity=90
+orbit_SemiMajorAxis=30
 type=observer
 \end{configfile}
-Note the inclination and mean longitude of 90 degrees, and that it is \texttt{hidden} and has no \texttt{halo}. 
+Note that it is \texttt{hidden} and has no \texttt{halo}. 
+The observer is attached to the Sun, therefore distance \texttt{orbit\_semiMajorAxis} is given in AU.
 
 \paragraph{Planet Observers}
 \label{sec:ssystem.ini:PlanetObserver}
 
 There are other ``observer'' locations for all planets \newFeature{0.19.2} which have moons: Earth, Mars, Jupiter, Saturn, Uranus, and Neptune.
-They have all been provided as neutral view locations above the Northern hemisphere of
-the respective planet. For example:
+For example:
 \begin{configfile}
 [earth_observer]
 name=Earth Observer
 parent=Earth
 halo=false
 hidden=true
-coord_func=ell_orbit
-orbit_Inclination=90
-orbit_MeanLongitude=90
-orbit_Period=100000000000
 orbit_SemiMajorAxis=149600000
-rot_obliquity=90
 type=observer
 \end{configfile}
 
-The distance \texttt{orbit\_semiMajorAxis} has been configured with a
-distance that resembles the semimajor axis of the respective planet:
-when you want to compare the views from Earth and from the observer,
-light time correction should be at least approximately equal.
+The distance \texttt{orbit\_semiMajorAxis} has been preconfigured \newFeature{23.1} with a
+distance that gives a good view of the planet with its moons. 
+Like for moons, the units are \km\ from the planet. 
 
 \subsection{File ssystem\_minor.ini}
 \label{sec:ssystem.ini:minor}

guide/ch_interface.tex

@@ -163,7 +163,20 @@ \subsection{Geographical Regions}
 of geographical regions. There is only one known habitable planet, one 
 humankind, and one sky. Stellarium users should overcome borders! 
 
-For ``region'' classification of sky cultures we use same regions (see \ref{sec:skycultures:region}) and we follow UN M49 geoscheme\footnote{https://unstats.un.org/unsd/methodology/m49/} with extensions for other planets.
+For the ``region'' classification of sky cultures we use the same regions (see \ref{sec:skycultures:region}), 
+and we follow the UN~M49 geoscheme\footnote{https://unstats.un.org/unsd/methodology/m49/} with extensions for other planets.
+
+\subsection{Observers}
+\label{sec:gui:location:observers}
+
+In the list of Planets you can find entries called \emph{Solar System Observer}, \emph{Jupiter Observer} and 
+similar for each major planet that has moons: Earth, Mars, Jupiter, Saturn, Uranus, and Neptune. 
+These are specialized locations. When switching to them, you will find yourself looking 
+onto the respective observed object (Sun, Jupiter, \ldots) from somewhat above the plane of the Solar system. 
+By pressing \key{\Alt+\arrowkeyleft}/\key{\Alt+\arrowkeyright} you can rotate around a vertical axis through the observed object.
+Likewise, by pressing \key{\Alt+\arrowkeyup}/\key{\Alt+\arrowkeydown} you can change the latitude of observation. Finally, 
+with \key{\Alt+Home}/\key{\Alt+End} you can change the distance from the observed object. 
+
 
 \section{The Configuration Window}
 \label{sec:gui:configuration}

plugins/ArchaeoLines/src/ArchaeoLines.cpp

@@ -373,7 +373,7 @@ void ArchaeoLines::update(double deltaTime)
 
 	static const double b_over_a=0.99664719;
 	const bool useGeocentric = !core->getUseTopocentricCoordinates();
-	const double latRad=useGeocentric ? 0.0 : static_cast<double>(loc.latitude)*M_PI_180;
+	const double latRad=useGeocentric ? 0.0 : static_cast<double>(loc.getLatitude())*M_PI_180;
 	const double u=std::atan(b_over_a*std::tan(latRad));
 	const double rhoSinPhiP=useGeocentric ? 0. : b_over_a*std::sin(u)+loc.altitude/6378140.0*std::sin(latRad);
 	const double rhoCosPhiP=useGeocentric ? 1. :          std::cos(u)+loc.altitude/6378140.0*std::cos(latRad);
@@ -418,8 +418,8 @@ void ArchaeoLines::update(double deltaTime)
 	southernMajorStandstillLine6->setDefiningAngle(lunarDEtopo[6] *180.0/M_PI);
 	southernMajorStandstillLine7->setDefiningAngle(lunarDEtopo[7] *180.0/M_PI);
 
-	zenithPassageLine->setDefiningAngle(static_cast<double>(loc.latitude));
-	nadirPassageLine->setDefiningAngle(static_cast<double>(-loc.latitude));
+	zenithPassageLine->setDefiningAngle(static_cast<double>(loc.getLatitude()));
+	nadirPassageLine->setDefiningAngle(static_cast<double>(-loc.getLatitude()));
 
 	// Selected object?
 	if (objMgr->getWasSelected())

plugins/ArchaeoLines/src/gui/ArchaeoLinesDialogLocations.cpp

@@ -85,13 +85,13 @@ void ArchaeoLinesDialogLocations::setLocationFromList(const QModelIndex& index)
 	switch (modalContext)
 	{
 		case 1:
-			al->setGeographicLocation1Latitude(static_cast<double>(loc.latitude));
-			al->setGeographicLocation1Longitude(static_cast<double>(loc.longitude));
+			al->setGeographicLocation1Latitude(static_cast<double>(loc.getLatitude()));
+			al->setGeographicLocation1Longitude(static_cast<double>(loc.getLongitude()));
 			al->setGeographicLocation1Label(loc.name);
 			break;
 		case 2:
-			al->setGeographicLocation2Latitude(static_cast<double>(loc.latitude));
-			al->setGeographicLocation2Longitude(static_cast<double>(loc.longitude));
+			al->setGeographicLocation2Latitude(static_cast<double>(loc.getLatitude()));
+			al->setGeographicLocation2Longitude(static_cast<double>(loc.getLongitude()));
 			al->setGeographicLocation2Label(loc.name);
 			break;
 		default:

plugins/Calendars/src/Calendar.cpp

@@ -152,23 +152,23 @@ double Calendar::direction(const StelLocation &locFrom, const StelLocation &locT
 	// We could do that, but south azimuth may cause problems.
 	//return StelLocation::getAzimuthForLocation(static_cast<double>(loc1.longitude), static_cast<double>(loc1.latitude),
 	//					   static_cast<double>(loc2.longitude), static_cast<double>(loc2.latitude));
-	const double longObs    = static_cast<double>(locFrom.longitude) * M_PI_180;
-	const double latObs     = static_cast<double>(locFrom.latitude ) * M_PI_180;
-	const double longTarget = static_cast<double>(locTo.longitude) * M_PI_180;
-	const double latTarget  = static_cast<double>(locTo.latitude ) * M_PI_180;
+	const double longObs    = static_cast<double>(locFrom.getLongitude()) * M_PI_180;
+	const double latObs     = static_cast<double>(locFrom.getLatitude() ) * M_PI_180;
+	const double longTarget = static_cast<double>(locTo.getLongitude()) * M_PI_180;
+	const double latTarget  = static_cast<double>(locTo.getLatitude() ) * M_PI_180;
 
 	double az = atan2(sin(longTarget-longObs), cos(latObs)*tan(latTarget)-sin(latObs)*cos(longTarget-longObs));
 	return StelUtils::fmodpos(M_180_PI * az, 360.0);
 }
 double Calendar::universalFromLocal(double rd_loc, const StelLocation &loc)
 {
 	//qDebug() << "universalFromLocal: Location " << loc.name << "longitude:" << loc.longitude;
-	return rd_loc-zoneFromLongitude(static_cast<double>(loc.longitude));
+	return rd_loc-zoneFromLongitude(static_cast<double>(loc.getLongitude()));
 }
 double Calendar::localFromUniversal(double rd_ut, const StelLocation &loc)
 {
 	//qDebug() << "localFromUniversal: Location " << loc.name << "longitude:" << loc.longitude;
-	return rd_ut+zoneFromLongitude(static_cast<double>(loc.longitude));
+	return rd_ut+zoneFromLongitude(static_cast<double>(loc.getLongitude()));
 }
 double Calendar::standardFromUniversal(double rd_ut, const StelLocation &loc)
 {
@@ -456,8 +456,8 @@ double Calendar::precession(double rd_dt)
 // return altitude of the sun at loc, degrees
 double Calendar::solarAltitude(double rd_ut, const StelLocation &loc)
 {
-	const double phiRad=static_cast<double>(loc.latitude)*M_PI_180;
-	const double psi=static_cast<double>(loc.longitude);
+	const double phiRad=static_cast<double>(loc.getLatitude())*M_PI_180;
+	const double psi=static_cast<double>(loc.getLongitude());
 	const double lambda=solarLongitude(rd_ut);
 
 	static StelCore *core = StelApp::getInstance().getCore();
@@ -873,8 +873,8 @@ double Calendar::lunarPhaseAtOrAfter(double phi, double rd_ut)
 // return altitude of the moon at loc, degrees (CC:UE 14:64)
 double Calendar::lunarAltitude(double rd_ut, const StelLocation &loc)
 {
-	double phiRad=static_cast<double>(loc.latitude)*M_PI_180;
-	double psi=static_cast<double>(loc.longitude);
+	double phiRad=static_cast<double>(loc.getLatitude())*M_PI_180;
+	double psi=static_cast<double>(loc.getLongitude());
 	double lambda=lunarLongitude(rd_ut);
 	double beta=lunarLatitude(rd_ut);
 
@@ -931,7 +931,7 @@ double Calendar::approxMomentOfDepression(double rd_loc, double alpha, bool earl
 // return sine of ... (CC:UE 14.69)
 double Calendar::sineOffset(double rd_loc, double alpha, const StelLocation &loc)
 {
-	const double phiRad=static_cast<double>(loc.latitude)*M_PI_180;
+	const double phiRad=static_cast<double>(loc.getLatitude())*M_PI_180;
 	const double tP=universalFromLocal(rd_loc, loc);
 	const double deltaRad=M_PI_180*declination(tP, 0., solarLongitude(tP));
 	return tan(phiRad)*tan(deltaRad)+sin(alpha*M_PI_180)/(cos(deltaRad)*cos(phiRad));
@@ -992,7 +992,7 @@ double Calendar::moonrise(int rd, const StelLocation &loc)
 	const double t=universalFromStandard(rd, loc);
 	const bool waning=lunarPhase(t) > 180.;
 	const double alt=observedLunarAltitude(t, loc);
-	const double lat=static_cast<double>(loc.latitude);
+	const double lat=static_cast<double>(loc.getLatitude());
 	const double offset=alt/(4.*(90.-fabs(lat)));
 
 	static const QDateTime j2k(QDate(2000, 1, 1), QTime(0, 0, 0), Qt::UTC);
@@ -1036,7 +1036,7 @@ double Calendar::moonset(int rd, const StelLocation &loc)
 	const double t=universalFromStandard(rd, loc);
 	const bool waxing=lunarPhase(t) < 180.;
 	const double alt=observedLunarAltitude(t, loc);
-	const double lat=static_cast<double>(loc.latitude);
+	const double lat=static_cast<double>(loc.getLatitude());
 	const double offset=alt/(4.*(90.-fabs(lat)));
 	double approx = t + 0.5 - offset;
 	if (waxing)

plugins/Calendars/src/NewHinduCalendar.cpp

@@ -354,7 +354,7 @@ int NewHinduCalendar::hinduCalendarYear(const double rd_ut)
 double NewHinduCalendar::hinduAscensionalDifference(const int rd, const StelLocation &loc)
 {
 	const double sinD=(1397./3438.)*hinduSine(hinduTropicalLongitude(rd));
-	const double phi=static_cast<double>(loc.latitude);
+	const double phi=static_cast<double>(loc.getLatitude());
 	const double diurnalRadius=hinduSine(90.+hinduArcsin(sinD));
 	const double tanPhi=hinduSine(phi)/hinduSine(90.+phi);
 	const double earthSine=sinD*tanPhi;
@@ -402,15 +402,15 @@ double NewHinduCalendar::hinduEquationOfTime(const double rd_ut)
 // return hindu time of sunrise (CC:UE 20.33)
 double NewHinduCalendar::hinduSunrise(const int rd)
 {
-	return rd+0.25+static_cast<double>(ujjain.longitude-hinduLocation.longitude)/360.-hinduEquationOfTime(rd)
+	return rd+0.25+static_cast<double>(ujjain.getLongitude()-hinduLocation.getLongitude())/360.-hinduEquationOfTime(rd)
 			+ (1577917828./(1582237828.*360.))*(hinduAscensionalDifference(rd, hinduLocation)+0.25*hinduSolarSiderealDifference(rd));
 }
 
 // 20.4 Alternatives
 // return hindu time of sunset (CC:UE 20.34)
 double NewHinduCalendar::hinduSunset(const int rd)
 {
-	return rd+0.75+static_cast<double>(ujjain.longitude-hinduLocation.longitude)/360.-hinduEquationOfTime(rd)
+	return rd+0.75+static_cast<double>(ujjain.getLongitude()-hinduLocation.getLongitude())/360.-hinduEquationOfTime(rd)
 			+ (1577917828./(1582237828.*360.))*(0.75*hinduSolarSiderealDifference(rd) - hinduAscensionalDifference(rd, hinduLocation));
 }
 // return hindu time  (CC:UE 20.35)

plugins/NavStars/src/NavStars.cpp

@@ -651,8 +651,8 @@ void NavStars::extraInfo(StelCore* core, const StelObjectP& selectedObject)
 
 	NavStarsCalculator calc;
 	calc.setUTC(StelUtils::julianDayToISO8601String(jd))
-		.setLatDeg(core->getCurrentLocation().latitude)
-		.setLonDeg(core->getCurrentLocation().longitude)
+		.setLatDeg(core->getCurrentLocation().getLatitude())
+		.setLonDeg(core->getCurrentLocation().getLongitude())
 		.setJd(jd)
 		.setJde(jde)
 		.setGmst(get_mean_sidereal_time(jd, jde));

plugins/Observability/src/Observability.cpp

@@ -1624,8 +1624,8 @@ void Observability::onLocationChanged(const StelLocation & location)
 {
    qDebug() << "[Observability] Location updated.";
 
-   mylat          = static_cast<double>(location.latitude)/Rad2Deg;
-   mylon          = static_cast<double>(location.longitude)/Rad2Deg;
+   mylat          = static_cast<double>(location.getLatitude())/Rad2Deg;
+   mylon          = static_cast<double>(location.getLongitude())/Rad2Deg;
    double currheight = (6371. + (location.altitude) / 1000.) / UA;
 
    double temp1   = currheight * std::cos(mylat);

plugins/RemoteControl/src/LocationService.cpp

@@ -170,15 +170,15 @@ void LocationService::post(const QByteArray& operation, const APIParameters &par
 		bool doneSomething = false;
 		bool ok = false;
 		float latitude = sLatitude.toFloat(&ok);
-		if(ok && (latitude - loc.latitude) != 0.0f)
+		if(ok && (latitude - loc.getLatitude()) != 0.0f)
 		{
-			loc.latitude = latitude;
+			loc.setLatitude(latitude);
 			doneSomething = true;
 		}
 		float longitude = sLongitude.toFloat(&ok);
-		if(ok && (longitude - loc.longitude) != 0.0f)
+		if(ok && (longitude - loc.getLongitude()) != 0.0f)
 		{
-			loc.longitude = longitude;
+			loc.setLongitude(longitude);
 			doneSomething = true;
 		}
 		int altitude = sAltitude.toInt(&ok);
@@ -194,7 +194,7 @@ void LocationService::post(const QByteArray& operation, const APIParameters &par
 		}
 		else if (!parameters.contains("name"))
 		{
-			loc.name=QString("%1, %2").arg(loc.latitude).arg(loc.longitude); // Force a preliminary name
+			loc.name=QString("%1, %2").arg(loc.getLatitude()).arg(loc.getLongitude()); // Force a preliminary name
 		}
 		if(!region.isEmpty() && region != loc.region)
 		{