/* solve a spherical triangle:
* A
* / \
* / \
* c / \ b
* / \
* / \
* B ____________ C
* a
*
* given A, b, c find B and a in range 0..B..2PI and 0..a..PI, respectively..
* cap and Bp may be NULL if not interested in either one.
* N.B. we pass in cos(c) and sin(c) because in many problems one of the sides
* remains constant for many values of A and b.
*/
static void solve_sphere(double A, double b, double cc, double sc, ref double cap, ref double Bp)
{
double cb = Math.Cos(b), sb = Math.Sin(b);
double sA, cA = Math.Cos(A);
double x, y;
double ca;
double B;
ca = cb * cc + sb * sc * cA;
if (ca > 1.0)
{
ca = 1.0;
}
if (ca < -1.0)
{
ca = -1.0;
}
cap = ca;
if (sc < 1e-7)
{
B = cc < 0 ? A : Math.PI - A;
}
else
{
sA = Math.Sin(A);
y = sA * sb * sc;
x = cb - ca * cc;
B = Math.Atan2(y, x);
}
Bp = AstroConvert.Range2Pi(B);
}
public static double FlipDecAxisRadians(double rad)
{
if (rad == 0.0)
{
return(rad);
}
bool isNegative = (rad < 0.0);
double absRad = AstroConvert.Range2Pi(Math.Abs(rad)); // Converts to an absolute value from 0-360
double flippedValue = Constants.TWO_PI - absRad;
if (isNegative)
{
flippedValue = flippedValue * -1.0;
}
return(flippedValue);
}
public static double FlipDecAxisDegrees(double degrees)
{
if (degrees == 0.0)
{
return(degrees);
}
bool isNegative = (degrees < 0.0);
double absDegrees = AstroConvert.Range360Degrees(Math.Abs(degrees)); // Converts to an absolute value from 0-360
double flippedValue = 360.0 - absDegrees;
if (isNegative)
{
flippedValue = flippedValue * -1.0;
}
return(flippedValue);
}
public AltAzCoordinate GetAltAz(double rightAscension, double declination, DateTime when)
{
_Transform.JulianDateTT = _Util.DateLocalToJulian(when);
_Transform.SetTopocentric(rightAscension, declination);
return(new AltAzCoordinate(_Transform.ElevationTopocentric, AstroConvert.RangeAzimuth(_Transform.AzimuthTopocentric)));
}
