public override bool HitTest(Ray3 ray, out double t)
{
ray = ray.Transform(InvPosition);
double dx = ray.Direction.X;
double dy = ray.Direction.Y;
double dz = ray.Direction.Z;
double x0 = ray.Position.X;
double y0 = ray.Position.Y;
double z0 = ray.Position.Z;
double a = dx * dx * dx * dx + dy * dy * dy * dy + dz * dz * dz * dz;
double b = 4.0 * dx * dx * dx * x0 + 4.0 * dy * dy * dy * y0 + 4.0 * dz * dz * dz;
double c = 6.0 * dx * dx * x0 * x0 - 5.0 * dx * dx + 6.0 * dy * dy * y0 * y0 - 5.0 * dy * dy + 6.0 * dz * dz * z0 * z0 - 5.0 * dz * dz;
double d = 4.0 * dx * x0 * x0 * x0 - 10.0 * dx * x0 + 4.0 * dy * y0 * y0 * y0 - 10.0 * dy * y0 + 4.0 * dz * z0 * z0 * z0;
double e = x0 * x0 * x0 * x0 - 5.0 * x0 * x0 + y0 * y0 * y0 * y0 - 5.0 * y0 * y0 + z0 * z0 * z0 * z0 - 5.0 * z0 * z0 + 11.8;
RealPolynomial poly = new RealPolynomial(a, b, c, d, e);
//poly /= new RealPolynomial(100000);
//poly.Normalize();
double ev = poly.Eval(1.0);
double[] cof = poly.FindRoots(MathUtil.Epsilon, false);
//double[] cof=RealPolynomial.SolveQuartic(a, b, c, d, e);
bool found = false;
t = double.MaxValue;
foreach (var tt in RealPolynomial.SolveQuadric(a, b, c))
{
if (tt > 1e-4 && tt < t)
{
t = tt;
found = true;
}
}
return(found);
}