public bool Intersects(Segment s)
{
Vector3D i1 = Vector3D.DneVector(), i2 = Vector3D.DneVector();
int numInt = 0;
if (SegmentType.Arc == Type)
{
if (SegmentType.Arc == s.Type)
{
numInt = Euclidean2D.IntersectionCircleCircle(Circle, s.Circle, out i1, out i2);
}
else
{
numInt = Euclidean2D.IntersectionLineCircle(P1, P2, s.Circle, out i1, out i2);
}
}
else
{
if (SegmentType.Arc == s.Type)
{
numInt = Euclidean2D.IntersectionLineCircle(s.P1, s.P2, Circle, out i1, out i2);
}
else
{
numInt = Euclidean2D.IntersectionLineLine(P1, P2, s.P1, s.P2, out i1);
}
}
// -1 can denote conincident segments (I'm not consistent in the impls above :/),
// and we are not going to include those for now.
if (numInt <= 0)
{
return(false);
}
if (numInt > 0)
{
if (IsPointOn(i1) && s.IsPointOn(i1))
{
return(true);
}
}
if (numInt > 1)
{
if (IsPointOn(i2) && s.IsPointOn(i2))
{
return(true);
}
}
return(false);
}
// Get the intersection points with a segment.
// Returns null if the segment is an arc coincident with the circle (infinite number of intersection points).
public Vector3D[] GetIntersectionPoints(Segment segment)
{
Vector3D p1, p2;
int result;
// Are we a line?
if (this.IsLine)
{
if (SegmentType.Arc == segment.Type)
{
Circle tempCircle = segment.Circle;
result = Euclidean2D.IntersectionLineCircle(this.P1, this.P2, tempCircle, out p1, out p2);
}
else
{
result = Euclidean2D.IntersectionLineLine(this.P1, this.P2, segment.P1, segment.P2, out p1);
p2 = Vector3D.DneVector();
}
}
else
{
if (SegmentType.Arc == segment.Type)
{
Circle tempCircle = segment.Circle;
result = Euclidean2D.IntersectionCircleCircle(tempCircle, this, out p1, out p2);
}
else
{
result = Euclidean2D.IntersectionLineCircle(segment.P1, segment.P2, this, out p1, out p2);
}
}
if (-1 == result)
{
return(null);
}
List <Vector3D> ret = new List <Vector3D>();
if (result >= 1 && segment.IsPointOn(p1))
{
ret.Add(p1);
}
if (result >= 2 && segment.IsPointOn(p2))
{
ret.Add(p2);
}
return(ret.ToArray());
}