model create wire on the surface from the uv space

注从occ demo 中onmakeface()

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//第一步创建曲面
	P1.SetCoord(35,-200,40);
	P2.SetCoord(50,-204,30);
	P3.SetCoord(65,-200,30);
	P4.SetCoord(35,-20,45);
	P5.SetCoord(45,-20,30);
	P6.SetCoord(65,-20,65);
	TColgp_Array2OfPnt array2(1,3,1,2);
	array2.SetValue(1,1,P1);
	array2.SetValue(2,1,P2);
	array2.SetValue(3,1,P3); 
	array2.SetValue(1,2,P4); 
	array2.SetValue(2,2,P5); 
	array2.SetValue(3,2,P6);
	
	Handle (Geom_BSplineSurface) BSplineSurf = GeomAPI_PointsToBSplineSurface(array2,3,8,GeomAbs_C2,0.001);
	
	TopoDS_Face aFace = BRepBuilderAPI_MakeFace(BSplineSurf);
//创建映射空间uv space
	//2d lines
	gp_Pnt2d P12d(0.9,0.1);
	gp_Pnt2d P22d(0.2,0.7);
	gp_Pnt2d P32d(0.02,0.1);

	Handle (Geom2d_Line) line1 = new Geom2d_Line(P12d,gp_Dir2d((0.2-0.9),(0.7-0.1)));
	Handle (Geom2d_Line) line2 = new Geom2d_Line(P22d,gp_Dir2d((0.02-0.2),(0.1-0.7)));
	Handle (Geom2d_Line) line3 = new Geom2d_Line(P32d,gp_Dir2d((0.9-0.02),(0.1-0.1)));


	//Edges are on the BSpline surface
	Edge1 = BRepBuilderAPI_MakeEdge(line1,BSplineSurf,0,P12d.Distance(P22d));
	Edge2 = BRepBuilderAPI_MakeEdge(line2,BSplineSurf,0,P22d.Distance(P32d));
	Edge3 = BRepBuilderAPI_MakeEdge(line3,BSplineSurf,0,P32d.Distance(P12d));

	Wire1 = BRepBuilderAPI_MakeWire(Edge1,Edge2,Edge3);

//创建wire 并指出方向。
	Wire1.Reverse();
	PinkFace = BRepBuilderAPI_MakeFace(aFace,Wire1);
	BRepLib::BuildCurves3d(PinkFace);

//分割线------------------------------------------------------------------------//tobe continue

需要对occ中uv space 进行深入理解