public void SphereIntersectionsNoIntersection()
{
Ellipsoid unitSphere = Ellipsoid.UnitSphere;
double[] intersections;
intersections = unitSphere.Intersections(new Vector3D(2.0, 0.0, 0.0), new Vector3D(0.0, 0.0, 1.0));
Assert.AreEqual(0, intersections.Length);
intersections = unitSphere.Intersections(new Vector3D(2.0, 0.0, 0.0), new Vector3D(0.0, 0.0, -1.0));
Assert.AreEqual(0, intersections.Length);
intersections = unitSphere.Intersections(new Vector3D(2.0, 0.0, 0.0), new Vector3D(0.0, 1.0, 0.0));
Assert.AreEqual(0, intersections.Length);
intersections = unitSphere.Intersections(new Vector3D(2.0, 0.0, 0.0), new Vector3D(0.0, -1.0, 0.0));
Assert.AreEqual(0, intersections.Length);
}
public void SphereIntersectionsTwoFromInside()
{
Ellipsoid unitSphere = Ellipsoid.UnitSphere;
double[] intersections;
intersections = unitSphere.Intersections(new Vector3D(0.0, 0.0, 0.0), new Vector3D(0.0, 0.0, 1.0));
Assert.AreEqual(2, intersections.Length);
Assert.AreEqual(-1.0, intersections[0], 1e-14);
Assert.AreEqual(1.0, intersections[1], 1e-14);
intersections = unitSphere.Intersections(new Vector3D(0.0, 0.5, 0.0), new Vector3D(0.0, 1.0, 0.0));
Assert.AreEqual(2, intersections.Length);
Assert.AreEqual(-1.5, intersections[0], 1e-14);
Assert.AreEqual(0.5, intersections[1], 1e-14);
intersections = unitSphere.Intersections(new Vector3D(0.0, 0.5, 0.0), new Vector3D(0.0, -1.0, 0.0));
Assert.AreEqual(2, intersections.Length);
Assert.AreEqual(-0.5, intersections[0], 1e-14);
Assert.AreEqual(1.5, intersections[1], 1e-14);
}