I have a Geom_Curve which is DownCasted from an Object and I'm sure the curve lying on the surface. My code as following:
TanShape = Handle(AIS_Shape)::DownCast(myCurrentIC->Current())->Shape();
const Handle(BRep_CurveRepresentation)& cr = itcr.Value();
const Handle(BRep_GCurve)& GC = *((Handle(BRep_GCurve)*)&cr);
I check the data for TanCurve and FaceSur and they are ok, but in the debug mode, I check the value of the entity for "Tan2dCurve" and it is 0xfefd0000 and vfpter is "CXX0030: Error: expression cannot be evaluated".
Who can help me, whether the problem come from the bug of "GeomProjLib" or I can't use the function for the 3D Curve which has already lied on the surface?