To find intersection point of a self-intersecting B-Spline curve

Hi,
There is no function like GeomAPI_InterCurveCurve. So the best idea is to convert the curve to 2D then find the intersecting points and trim the curve and then conver to 3d Curve.

Here is the sample Code, I think this will help u.

Consider u r having two 3D curve,

//First step Have a handle for the Curve

Handle(Geom_Curve) Line3dCurve1;
Handle(Geom_Curve) Line3dCurve1;

// Have the Axis

gp_Ax3 theAxe(gp::XOY()); //XOY can be changed according to the axis that you are using

gp_Pln PL(theAxe);

//Converting 3D to 2D Curve

Handle(Geom2d_Curve) Line2dCurve1 = GeomAPI::To2d(Line3dCurve1,PL);
Handle(Geom2d_Curve) Line2dCurve2 = GeomAPI::To2d(Line3dCurve2,Line2dCurve2 ); //Put (Line3dCurve2,Line2dCurve1 ); if u want to find the same intersection Points.

//Finding the Intersection Points
Geom2dAPI_InterCurveCurve Intect1= Geom2dAPI_InterCurveCurve(Line2dCurve1 ,curve);

int totIntPoints = Intect1.NbPoints();

//totIntPoints will return the total no of intersection Point

gp_Pnt2d IntPoint2d = Intect1.Point(1); // Will return first intersection Point. If will return error if no intersection points are present. Similarly Intect1.Point(2) will return 2nd intersection Point if it is present.Intect1.Point(i) will return ith intersection and i value should be equal or less than totIntPoints.
gp_Pnt IntPoint(IntPoint2d.X(),IntPoint2d.Y(),0);

//Then trim the curve with he help of the Points u get.
//Then conver to 3D using

Handle(Geom_Curve) LineCurve3D = GeomAPI::To2d(Line2dCurve1 ,PL);

Regards,
Vidhyan