occ常用几何功能记录

1、线(直线、射线)与面相交

BRepClass3d_Intersector3d::Perform (const gp_Lin& L, const Standard_Real Prm, const Standard_Real Tol, const TopoDS_Face& F)

BRepExtrema_ExtCF::Perform(const TopoDS_Edge& E,const TopoDS_Face& F);

Extrema_ExtCS(const Adaptor3d_Curve& C, const Adaptor3d_Surface& S, const Standard_Real TolC, const Standard_Real TolS);

2、计算曲面face的外包闭合边界线wire

ShapeAnalysis_FreeBounds(const TopoDS_Shape& shape, const Standard_Real toler, const Standard_Boolean splitclosed = Standard_False, const Standard_Boolean splitopen = Standard_True);

如果面开开有洞口的话，GetClosedWires()会返回多组wire

3、TopExp_Explorer和TopoDS_Iterator

TopExp_Explore是用TopoDS_Iterator实现的，TopoDS_Iterator只能遍历一级子对象

比如想获取TopoDS_Compound的直接子对象，就可以用TopoDS_Iterator