/// <summary>
/// Expand the bounding box to include the given bounding sphere
/// </summary>
/// <param name="sh"></param>
/// <exception cref="NotImplementedException"></exception>
public void ExpandBy(IBoundingSphere sh)
{
if (!sh.Valid())
{
return;
}
if (sh.Center.X - sh.Radius < _min.X)
{
_min.X = sh.Center.X - sh.Radius;
}
if (sh.Center.X + sh.Radius > _max.X)
{
_max.X = sh.Center.X + sh.Radius;
}
if (sh.Center.Y - sh.Radius < _min.Y)
{
_min.Y = sh.Center.Y - sh.Radius;
}
if (sh.Center.Y + sh.Radius > _max.Y)
{
_max.Y = sh.Center.Y + sh.Radius;
}
if (sh.Center.Z - sh.Radius < _min.Z)
{
_min.Z = sh.Center.Z - sh.Radius;
}
if (sh.Center.Z + sh.Radius > _max.Z)
{
_max.Z = sh.Center.Z + sh.Radius;
}
}
private bool Intersects(IBoundingSphere bs)
{
if (!bs.Valid())
{
return(true);
}
var startToCenter = Start - bs.Center;
double c = startToCenter.LengthSquared() - System.Math.Pow(bs.Radius, 2);
if (c < 0.0)
{
return(true);
}
var startToEnd = End - Start;
double a = startToEnd.LengthSquared();
double b = Vector3.Dot(startToCenter, startToEnd) * 2.0;
double d = b * b - 4.0 * a * c;
if (d < 0.0)
{
return(false);
}
d = System.Math.Sqrt(d);
double div = 1.0 / (2.0 * a);
double r1 = (-b - d) * div;
double r2 = (-b + d) * div;
if (r1 <= 0.0 && r2 <= 0.0)
{
return(false);
}
if (r1 >= 1.0 && r2 >= 1.0)
{
return(false);
}
if (IntersectionLimit == IntersectionLimitModes.LimitNearest && 0 != Intersections.Count())
{
if (startToCenter.Length() > Intersections.First().StartToIntersectionDist)
{
return(false);
}
//double ratio = (startToCenter.Length() - bs.Radius) / System.Math.Sqrt(a);
//if (ratio >= Intersections.First().Ratio) return false;
}
// passed all the rejection tests so line must intersect bounding sphere, return true.
return(true);
}