/// <summary>
/// Initializes the transform using the parameters from the specified coordinate system information
/// </summary>
/// <param name="projInfo">A ProjectionInfo class contains all the standard and custom parameters needed to initialize this transform</param>
protected override void OnInit(ProjectionInfo projInfo)
{
/* read some Parameters,
* here Latitude Truescale */
double ts = 0;
if(projInfo.StandardParallel1 != null) ts = projInfo.StandardParallel1.Value*Math.PI/180;
_C_x = ts;
/* we want Bessel as fixed ellipsoid */
A = 6377397.155;
E = Math.Sqrt(Es = 0.006674372230614);
/* if latitude of projection center is not set, use 49d30'N */
Phi0 = projInfo.LatitudeOfOrigin != null ? projInfo.GetPhi0() : 0.863937979737193;
/* if center long is not set use 42d30'E of Ferro - 17d40' for Ferro */
/* that will correspond to using longitudes relative to greenwich */
/* as input and output, instead of lat/long relative to Ferro */
Lam0 = projInfo.CentralMeridian != null ? projInfo.GetLam0() : 0.7417649320975901 - 0.308341501185665;
/* if scale not set default to 0.9999 */
K0 = projInfo.CentralMeridian != null ? projInfo.GetLam0() : 0.9999;
if (!projInfo.Parameters.ContainsKey("czech")) return;
int temp = projInfo.ParamI("czech");
if (temp != 0) _czech = true;
}
/// <summary>
/// Initializes the transform using the parameters from the specified coordinate system information
/// </summary>
/// <param name="projInfo">A ProjectionInfo class contains all the standard and custom parameters needed to initialize this transform</param>
protected override void OnInit(ProjectionInfo projInfo)
{
if (!projInfo.Parameters.ContainsKey("bns")) return;
if (projInfo.ParamI("bns") != 0) _noskew = true;
}
/// <summary>
/// Initializes the transform using the parameters from the specified coordinate system information
/// </summary>
/// <param name="projInfo">A ProjectionInfo class contains all the standard and custom parameters needed to initialize this transform</param>
protected override void OnInit(ProjectionInfo projInfo)
{
double con;
double f;
double d;
double toRadians = projInfo.GeographicInfo.Unit.Radians;
_rot = projInfo.ParamI("no_rot") == 0;
bool azi = projInfo.ParamD("alpha") != 0.0;
if (azi)
{
_lamc = projInfo.ParamD("lonc")*toRadians;
_alpha = projInfo.ParamD("alpha") *toRadians;
if (Math.Abs(_alpha) < Tol ||
Math.Abs(Math.Abs(Phi0) - HalfPi) <= Tol ||
Math.Abs(Math.Abs(_alpha) - HalfPi) <= Tol)
throw new ProjectionException(32);
}
else
{
_lam1 = projInfo.GetLam1();
_phi1 = projInfo.GetPhi1();
_lam2 = projInfo.GetLam2();
_phi2 = projInfo.GetPhi2();
if(Math.Abs(_phi1 - _phi2) <= Tol ||
(con = Math.Abs(_phi1)) <= Tol ||
Math.Abs(con - HalfPi) <= Tol ||
Math.Abs(Math.Abs(Phi0) - HalfPi) <= Tol ||
Math.Abs(Math.Abs(_phi2) - HalfPi) <= Tol)
{
throw new ProjectionException(33);
}
}
_ellips = Es > 0;
double com = _ellips ? Math.Sqrt(OneEs) : 1;
if (Math.Abs(Phi0) > EPS10)
{
double sinph0 = Math.Sin(Phi0);
double cosph0 = Math.Cos(Phi0);
if (_ellips)
{
con = 1 - Es*sinph0*sinph0;
_bl = cosph0*cosph0;
_bl = Math.Sqrt(1 + Es*_bl*_bl/OneEs);
_al = _bl*K0*com/con;
d = _bl*com/(cosph0*Math.Sqrt(con));
}
else
{
_bl = 1;
_al = K0;
d = 1/cosph0;
}
if ((f = d*d - 1) <= 0)
{
f = 0;
}
else
{
f = Math.Sqrt(f);
if (Phi0 < 0) f = -f;
}
_el = f += d;
if (_ellips)
{
_el *= Math.Pow(Proj.Tsfn(Phi0, sinph0, E), _bl);
}
else
{
_el *= TSFN0(Phi0);
}
}
else
{
_bl = 1/com;
_al = K0;
_el = d = f = 1;
}
if(azi)
{
_gamma = Math.Asin(Math.Sin(_alpha)/d);
Lam0 = _lamc - Math.Asin((.5*(f - 1/f))*Math.Tan(_gamma))/_bl;
}
else
{
double h;
double l;
if(_ellips)
{
h = Math.Pow(Proj.Tsfn(_phi1, Math.Sin(_phi1), E), _bl);
l = Math.Pow(Proj.Tsfn(_phi2, Math.Sin(_phi2), E), _bl);
}
else
{
h = TSFN0(_phi1);
l = TSFN0(_phi2);
}
f = _el/h;
double p = (l - h)/(l + h);
double j = _el*_el;
j = (j - l*h)/(j + l*h);
if ((con = _lam1 - _lam2) < -Math.PI)
{
_lam2 -= Math.PI*2;
}
else if (con > Math.PI)
{
_lam2 += Math.PI*2;
}
Lam0 = Proj.Adjlon(.5*(_lam1 + _lam2) - Math.Atan(j*Math.Tan(.5*_bl*(_lam1 - _lam2))/p)/_bl);
_gamma = Math.Atan(2*Math.Sin(_bl*Proj.Adjlon(_lam1 - Lam0))/(f - 1/f));
_alpha = Math.Asin(d*Math.Sin(_gamma));
}
_singam = Math.Sin(_gamma);
_cosgam = Math.Cos(_gamma);
if(projInfo.ParamI("rot_conv") != 0)
{
f = _gamma;
}
else
{
f = _alpha;
}
_sinrot = Math.Sin(f);
_cosrot = Math.Cos(f);
if(projInfo.ParamI("no_uoff") != 0)
{
_u0 = 0;
}
else
{
_u0 = Math.Abs(_al*Math.Atan(Math.Sqrt(d*d - 1)/_cosrot)/_bl);
}
if (Phi0 < 0) _u0 = -_u0;
}