/// <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.IsSouth)
{
Y0 = 10000000;
X0 = 500000;
int zone;
if (projInfo.Zone != null)
{
zone = projInfo.Zone.Value;
if (zone <= 0 || zone > 60)
{
throw new ProjectionException(35);
}
zone -= 1;
}
else
{
zone = (int)Math.Floor((Proj.Adjlon(Lam0) + Math.PI) * 30 / Math.PI);
if (zone < 0)
{
zone = 0;
}
if (zone >= 60)
{
zone = 59;
}
}
Lam0 = (zone + .5) * Math.PI / 30 - Math.PI;
K0 = 0.9996;
Phi0 = 0;
}
base.OnInit(projInfo);
}
/// <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 pp;
/* get control point locations */
double phi1 = projInfo.GetPhi1();
double lam1 = projInfo.GetLam1();
double phi2 = projInfo.GetPhi2();
double lam2 = projInfo.GetLam2();
if (phi1 == phi2 && lam1 == lam2)
{
throw new ProjectionException(-25);
}
Lam0 = Proj.Adjlon(0.5 * (lam1 + lam2));
_dlam2 = Proj.Adjlon(lam2 - lam1);
_cp1 = Math.Cos(phi1);
_cp2 = Math.Cos(phi2);
_sp1 = Math.Sin(phi1);
_sp2 = Math.Sin(phi2);
_cs = _cp1 * _sp2;
_sc = _sp1 * _cp2;
_ccs = _cp1 * _cp2 * Math.Sin(_dlam2);
_z02 = Proj.Aacos(_sp1 * _sp2 + _cp1 * _cp2 * Math.Cos(_dlam2));
_hz0 = .5 * _z02;
double A12 = Math.Atan2(_cp2 * Math.Sin(_dlam2),
_cp1 * _sp2 - _sp1 * _cp2 * Math.Cos(_dlam2));
_ca = Math.Cos(pp = Proj.Aasin(_cp1 * Math.Sin(A12)));
_sa = Math.Sin(pp);
_lp = Proj.Adjlon(Math.Atan2(_cp1 * Math.Cos(A12), _sp1) - _hz0);
_dlam2 *= .5;
_lamc = HalfPi - Math.Atan2(Math.Sin(A12) * _sp1, Math.Cos(A12)) - _dlam2;
_thz0 = Math.Tan(_hz0);
_rhshz0 = .5 / Math.Sin(_hz0);
_r2z0 = 0.5 / _z02;
_z02 *= _z02;
}
private static PhiLam Convert(PhiLam input, bool inverse, NadTable table)
{
if (input.Lambda == HUGE_VAL)
{
return(input);
}
// Normalize input to ll origin
PhiLam tb = input;
tb.Lambda -= table.LowerLeft.Lambda;
tb.Phi -= table.LowerLeft.Phi;
tb.Lambda = Proj.Adjlon(tb.Lambda - Math.PI) + Math.PI;
PhiLam t = NadInterpolate(tb, table);
if (inverse)
{
PhiLam del, dif;
int i = MAX_TRY;
if (t.Lambda == HUGE_VAL)
{
return(t);
}
t.Lambda = tb.Lambda + t.Lambda;
t.Phi = tb.Phi - t.Phi;
do
{
del = NadInterpolate(t, table);
/* This case used to return failure, but I have
* changed it to return the first order approximation
* of the inverse shift. This avoids cases where the
* grid shift *into* this grid came from another grid.
* While we aren't returning optimally correct results
* I feel a close result in this case is better than
* no result. NFW
* To demonstrate use -112.5839956 49.4914451 against
* the NTv2 grid shift file from Canada. */
if (del.Lambda == HUGE_VAL)
{
System.Diagnostics.Debug.WriteLine(ProjectionMessages.InverseShiftFailed);
break;
}
t.Lambda -= dif.Lambda = t.Lambda - del.Lambda - tb.Lambda;
t.Phi -= dif.Phi = t.Phi + del.Phi - tb.Phi;
} while (i-- > 0 && Math.Abs(dif.Lambda) > TOL && Math.Abs(dif.Phi) > TOL);
if (i < 0)
{
System.Diagnostics.Debug.WriteLine(ProjectionMessages.InvShiftConvergeFailed);
t.Lambda = t.Phi = HUGE_VAL;
return(t);
}
input.Lambda = Proj.Adjlon(t.Lambda + table.LowerLeft.Lambda);
input.Phi = t.Phi + table.LowerLeft.Phi;
}
else
{
if (t.Lambda == HUGE_VAL)
{
input = t;
}
else
{
input.Lambda -= t.Lambda;
input.Phi += t.Phi;
}
}
return(input);
}
/// <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;
}
}
