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Datum shift optimization (precompute ellipsoid constants)

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+ projections code unification
This commit is contained in:
Martin Tůma
2018-05-17 22:41:56 +02:00
parent b3940283a8
commit a486f9e78d
15 changed files with 98 additions and 105 deletions
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26
src/map/lambertazimuthal.cpp
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@ -16,19 +16,17 @@ LambertAzimuthal::LambertAzimuthal(const Ellipsoid *ellipsoid,
_lon0 = deg2rad(longitudeOrigin);
_a = ellipsoid->radius();
_es = ellipsoid->es();
_e = sqrt(_es);
_es2 = 2.0 * ellipsoid->flattening() - ellipsoid->flattening()
* ellipsoid->flattening();
_es = sqrt(_es2);
double q0 = (1.0 - _es2) * ((sin(lat0) / (1.0 - _es2 * sin2(lat0)))
- ((1.0/(2.0*_es)) * log((1.0 - _es * sin(lat0)) / (1.0 + _es
double q0 = (1.0 - _es) * ((sin(lat0) / (1.0 - _es * sin2(lat0)))
- ((1.0/(2.0*_e)) * log((1.0 - _e * sin(lat0)) / (1.0 + _e
* sin(lat0)))));
_qP = (1.0 - _es2) * ((1.0 / (1.0 - _es2)) - ((1.0/(2.0*_es))
* log((1.0 - _es) / (1.0 + _es))));
_qP = (1.0 - _es) * ((1.0 / (1.0 - _es)) - ((1.0/(2.0*_e))
* log((1.0 - _e) / (1.0 + _e))));
_beta0 = asin(q0 / _qP);
_Rq = _a * sqrt(_qP / 2.0);
_D = _a * (cos(lat0) / sqrt(1.0 - _es2 * sin2(lat0))) / (_Rq * cos(_beta0));
_D = _a * (cos(lat0) / sqrt(1.0 - _es * sin2(lat0))) / (_Rq * cos(_beta0));
}
PointD LambertAzimuthal::ll2xy(const Coordinates &c) const
@ -36,8 +34,8 @@ PointD LambertAzimuthal::ll2xy(const Coordinates &c) const
double lon = deg2rad(c.lon());
double lat = deg2rad(c.lat());
double q = (1.0 - _es2) * ((sin(lat) / (1.0 - _es2 * sin2(lat)))
- ((1.0/(2.0*_es)) * log((1.0 - _es * sin(lat)) / (1.0 + _es
double q = (1.0 - _es) * ((sin(lat) / (1.0 - _es * sin2(lat)))
- ((1.0/(2.0*_e)) * log((1.0 - _e * sin(lat)) / (1.0 + _e
* sin(lat)))));
double beta = asin(q / _qP);
double B = _Rq * sqrt(2.0 / (1.0 + sin(_beta0) * sin(beta) + (cos(_beta0)
@ -52,8 +50,8 @@ PointD LambertAzimuthal::ll2xy(const Coordinates &c) const
Coordinates LambertAzimuthal::xy2ll(const PointD &p) const
{
double es4 = _es2 * _es2;
double es6 = _es2 * es4;
double es4 = _es * _es;
double es6 = _es * es4;
double rho = sqrt(sqr((p.x() - _falseEasting) / _D) + sqr(_D * (p.y()
- _falseNorthing)));
@ -64,7 +62,7 @@ Coordinates LambertAzimuthal::xy2ll(const PointD &p) const
double lon = _lon0 + atan((p.x() - _falseEasting) * sin(C) / (_D * rho
* cos(_beta0) * cos(C) - sqr(_D) * (p.y() - _falseNorthing) * sin(_beta0)
* sin(C)));
double lat = betaS + ((_es2/3.0 + 31.0*es4/180.0 + 517.0*es6/5040.0)
double lat = betaS + ((_es/3.0 + 31.0*es4/180.0 + 517.0*es6/5040.0)
* sin(2.0*betaS)) + ((23.0*es4/360.0 + 251.0*es6/3780.0) * sin(4.0*betaS))
+ ((761.0*es6/45360.0)*sin(6.0*betaS));