public override Intersection[] LocalIntersect(Ray localRay)
{
LocalRay = localRay;
if (MathF.Abs(LocalRay.Direction.y) < Arithmetic.EPSILON)
{
return(new Intersection[0]);
}
else
{
float t = -localRay.Origin.y / localRay.Direction.y;
Intersection i1 = new Intersection(t, this);
return(Intersect.Intersections(i1));
}
}
public override Intersection[] LocalIntersect(Ray localRay)
{
Tuple sphereToRay = localRay.Origin - new Tuple(0, 0, 0, 1);
float a = localRay.Direction.Dot(localRay.Direction);
float b = 2 * localRay.Direction.Dot(sphereToRay);
float c = sphereToRay.Dot(sphereToRay) - 1;
float discriminant = (b * b) - 4 * a * c;
if (discriminant < 0)
{
Intersection[] empty = new Intersection[0];
return(empty);
}
Intersection i1 = new Intersection((-b - MathF.Sqrt(discriminant)) / (2 * a), this);
Intersection i2 = new Intersection((-b + MathF.Sqrt(discriminant)) / (2 * a), this);
return(Intersect.Intersections(i1, i2));
}