use planet 3D position provided by stellarium directly

src/core/modules/Star.hpp

@@ -237,15 +237,12 @@ struct Star
    }
 
    //to get new 3D cartesian position for parallax effect given current star 3D cartesian position, planet orbital period and radius and current delta time from catalog epoch
-   inline void getPlxEffect(double plx, Vec3f& bS, double operiod, double oradius, double dyrs) const {
+   inline void getPlxEffect(double plx, Vec3f& bS, const Vec3d diffPos) const {
 		if (plx <= 0) return;
 		Vec3d bSd(bS[0], bS[1], bS[2]);
 		bSd.normalize();
 		bSd *= 1000./ plx;
-		// remainder of dt in dyrs divided by period
-		double dt = fmod(dyrs, operiod);  // to get phase of the orbit
-		Vec3d b0Ecl(oradius * cos(2 * M_PI / operiod * dt), oradius * sin(2 * M_PI / operiod * dt), 0.);
-		bS = (bSd + b0Ecl * MAS2RAD * 1000.).toVec3f();
+		bS = (bSd + diffPos * MAS2RAD * 1000.).toVec3f();
    }
 };
 

src/core/modules/StarMgr.cpp

@@ -45,6 +45,7 @@
 #include "Planet.hpp"
 #include "StelUtils.hpp"
 #include "StelHealpix.hpp"
+#include "SolarSystem.hpp"
 
 #include <QTextStream>
 #include <QFile>
@@ -1242,16 +1243,26 @@ void StarMgr::draw(StelCore* core)
 				maxMagStarName = x;
 		}
 		int zone;
-		const double withParallax = core->getUseParallax() * core->getParallaxFactor();
-		double orbital_period = core->getCurrentPlanet()->getSiderealPeriod() / 365.25;  // in earth years
-		// get orbital_radius in AU using Kepler's third law
-		double orbital_radius = pow(orbital_period, 2.0/3.0);
+		double withParallax = core->getUseParallax() * core->getParallaxFactor();
+		Vec3d diffPos(0., 0., 0.);
+		if (withParallax) {
+			static SolarSystem *ssystem=GETSTELMODULE(SolarSystem);
+			const PlanetP earth = ssystem->getEarth();
+			// diff between earth location at STAR_CATALOG_JDEPOCH and current location
+			Vec3d earthPosCatalog = earth->getHeliocentricEclipticPos(STAR_CATALOG_JDEPOCH);
+			Vec3d PosNow = core->getCurrentPlanet()->getHeliocentricEclipticPos(core->getJDE());
+			double obliquity = earth->getRotObliquity(core->getJDE());  // need to always use Earth's obliquity because thats what the catalog is based on
+			// Transform from heliocentric ecliptic to equatorial coordinates
+			earthPosCatalog.set(earthPosCatalog[0], earthPosCatalog[1]*cos(obliquity)-earthPosCatalog[2]*sin(obliquity), earthPosCatalog[1]*sin(obliquity)+earthPosCatalog[2]*cos(obliquity));
+			PosNow.set(PosNow[0], PosNow[1]*cos(obliquity)-PosNow[2]*sin(obliquity), PosNow[1]*sin(obliquity)+PosNow[2]*cos(obliquity));
+			diffPos = PosNow - earthPosCatalog;
+		}
 		for (GeodesicSearchInsideIterator it1(*geodesic_search_result,z->level);(zone = it1.next()) >= 0;)
-			z->draw(&sPainter, zone, true, rcmag_table, limitMagIndex, core, maxMagStarName, names_brightness, viewportCaps, withAberration, velf, withParallax, orbital_period, orbital_radius);
+			z->draw(&sPainter, zone, true, rcmag_table, limitMagIndex, core, maxMagStarName, names_brightness, viewportCaps, withAberration, velf, withParallax, diffPos);
 		for (GeodesicSearchBorderIterator it1(*geodesic_search_result,z->level);(zone = it1.next()) >= 0;)
-			z->draw(&sPainter, zone, false, rcmag_table, limitMagIndex, core, maxMagStarName,names_brightness, viewportCaps, withAberration, velf, withParallax, orbital_period, orbital_radius);
+			z->draw(&sPainter, zone, false, rcmag_table, limitMagIndex, core, maxMagStarName,names_brightness, viewportCaps, withAberration, velf, withParallax, diffPos);
 		// always check the last zone because it is a global zone
-		z->draw(&sPainter, (20<<(z->level<<1)), false, rcmag_table, limitMagIndex, core, maxMagStarName, names_brightness, viewportCaps, withAberration, velf, withParallax, orbital_period, orbital_radius);
+		z->draw(&sPainter, (20<<(z->level<<1)), false, rcmag_table, limitMagIndex, core, maxMagStarName, names_brightness, viewportCaps, withAberration, velf, withParallax, diffPos);
 	}
 	exit_loop:
 

src/core/modules/ZoneArray.cpp

@@ -425,7 +425,7 @@ template<class Star>
 void SpecialZoneArray<Star>::draw(StelPainter* sPainter, int index, bool isInsideViewport, const RCMag* rcmag_table,
 				  int limitMagIndex, StelCore* core, int maxMagStarName, float names_brightness,
 				  const QVector<SphericalCap> &boundingCaps,
-				  const bool withAberration, const Vec3f vel, const double withParallax, double operiod, double oradius) const
+				  const bool withAberration, const Vec3f vel, const double withParallax, const Vec3d diffPos) const
 {
 	StelSkyDrawer* drawer = core->getSkyDrawer();
 	Vec3f vf;
@@ -500,7 +500,7 @@ void SpecialZoneArray<Star>::draw(StelPainter* sPainter, int index, bool isInsid
 		}
 
 		if (withParallax) {
-			s->getPlxEffect(withParallax * Plx, vf, operiod, oradius, dyrs);
+			s->getPlxEffect(withParallax * Plx, vf, diffPos);
 		}
 
 		// Aberration: vf contains Equatorial J2000 position.

src/core/modules/ZoneArray.hpp

@@ -110,7 +110,7 @@ class ZoneArray
 					  const RCMag* rcmag_table, int limitMagIndex, StelCore* core,
 					  int maxMagStarName, float names_brightness,
 					  const QVector<SphericalCap>& boundingCaps,
-					  const bool withAberration, const Vec3f vel, const double withParallax, double operiod, double oradius) const = 0;
+					  const bool withAberration, const Vec3f vel, const double withParallax, const Vec3d diffPos) const = 0;
 
 	//! Get whether or not the catalog was successfully loaded.
 	//! @return @c true if at least one zone was loaded, otherwise @c false
@@ -182,7 +182,7 @@ class SpecialZoneArray : public ZoneArray
 	          const RCMag *rcmag_table, int limitMagIndex, StelCore* core,
 	          int maxMagStarName, float names_brightness,
 	          const QVector<SphericalCap>& boundingCaps,
-	          const bool withAberration, const Vec3f vel, const double withParallax, double operiod, double oradius) const override;
+	          const bool withAberration, const Vec3f vel, const double withParallax, const Vec3d diffPos) const override;
 
 	void searchAround(const StelCore* core, int index,const Vec3d &v,double cosLimFov,
 	                  QList<StelObjectP > &result) override;