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feature/19
Daniel Warner 2011-04-09 19:56:35 +01:00
parent 9e89b87d31
commit f21109960d
1 changed files with 15 additions and 1 deletions
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16
Eci.cpp
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@ -13,16 +13,30 @@ Eci::Eci(const Julian &date, const CoordGeodetic &geo)
*/
const double theta = date_.ToLocalMeanSiderealTime(longitude);
/*
* take into account earth flattening
*/
const double c = 1.0 / sqrt(1.0 + Globals::F() * (Globals::F() - 2.0) * pow(sin(latitude), 2.0));
const double s = pow(1.0 - Globals::F(), 2.0) * c;
const double achcp = (Globals::XKMPER() * c + altitude) * cos(latitude);
/*
* X position in km
* Y position in km
* Z position in km
* W magnitude in km
*/
position_.SetX(achcp * cos(theta));
position_.SetY(achcp * sin(theta));
position_.SetZ((Globals::XKMPER() * s + altitude) * sin(latitude));
position_.SetW(position_.GetMagnitude());
/*
* X velocity in km/s
* Y velocity in km/s
* Z velocity in km/s
* W magnitude in km/s
*/
velocity_.SetX(-mfactor * position_.GetY());
velocity_.SetY(mfactor * position_.GetX());
velocity_.SetZ(0.0);