public static double SolveParam_2(double len, double r1, double r2)
{
Func <double, double> f = (a) =>
{
double fs1, fc1;
FresnelUtils.Fresnel(a / (r1 * sqrtpi), out fs1, out fc1);
double fs2, fc2;
FresnelUtils.Fresnel(a / (r2 * sqrtpi), out fs2, out fc2);
double fc21 = (fc2 - fc1);
double fs21 = (fs2 - fs1);
return(a * a * SysMath.PI * (fc21 * fc21 + fs21 * fs21) - len * len);
};
int maxEval = 50; // 30
try
{
double min = 0;
double max = SysMath.Min(SysMath.Abs(r1), SysMath.Abs(r2)) * MAX_L;
return(Solver.Solve(f, min, max, Solver.Type.Brent, Solver.DEFAULT_ABSOLUTE_ACCURACY, maxEval));
}
catch (Exception e)
{
Debug.WriteLine(e);
throw;
}
}
public static void Clotho(double s, bool invertY, double a, out double x, out double y)
{
double a_sqrtpi = a * sqrtpi;
double fs, fc;
FresnelUtils.Fresnel(s / a_sqrtpi, out fs, out fc);
x = a_sqrtpi * fc;
y = a_sqrtpi * fs;
if (invertY)
{
y = -y;
}
}