ShapeFix_Face not working

[R G W]

Hi bros, i'm RGW.
Recently I ran into another problem when rebuilding surfaces. The basic discussion of the rebuilding surface problem can be found in this question. http://analysissitus.org/forum/inde...nvert-geom_bsplinesurface-to-topods_face.249/

The problem I have now is that when I rebuild a surface, ShapeFix_Face doesn't work, or it doesn't achieve the desired effect.
When I checked the status of ShapeFix_Face, it reported ShapeExtend_DONE2, that is, the direction of some wires was fixed, and the results are as follows.
Has anyone encountered the same error and can give me some suggestions?

wrong result:



correct result:

 

[R G W]

Here is my demo.

#include <fstream>
#include <vector>

//OpenCascade include
#include <TopoDS_Shape.hxx>
#include <BRep_Builder.hxx>
#include <BRepTools.hxx>
#include <ShapeAnalysis.hxx>
#include <TopoDS.hxx>
#include <TopExp.hxx>
#include <BRepBuilderAPI_NurbsConvert.hxx>
#include <GeomConvert.hxx>
#include <Geom_BSplineSurface.hxx>
#include <TopExp_Explorer.hxx>
#include <BRepBuilderAPI_MakeWire.hxx>
#include <BRepBuilderAPI_MakeEdge.hxx>
#include <BRepBuilderAPI_MakeFace.hxx>
#include <ShapeFix_Face.hxx>

#include "viewer.h"

using namespace std;

int main()
{
    Viewer vout(50, 50, 500, 500);
    TopoDS_Shape myshape;
    BRep_Builder b;
    std::ifstream is;
    is.open("1");
    BRepTools::Read(myshape, is, b);
    is.close();

    TopTools_IndexedMapOfShape wires_map;
    TopoDS_Face faceo = TopoDS::Face(myshape);
    TopoDS_Wire outer_wire = ShapeAnalysis::OuterWire(faceo);
    TopExp::MapShapes(faceo, TopAbs_WIRE, wires_map);
    BRepBuilderAPI_NurbsConvert nurbs_convert;
    nurbs_convert = BRepBuilderAPI_NurbsConvert(faceo);
    nurbs_convert.Perform(faceo);
    TopoDS_Shape face_shape = nurbs_convert.Shape();
    Handle(Geom_Surface) h_geomface = BRep_Tool::Surface(TopoDS::Face(face_shape));
    Handle(Geom_BSplineSurface)h_bsurface = GeomConvert::SurfaceToBSplineSurface(h_geomface);
   
    std::vector<TopoDS_Wire> inner_wires;
    for (int j = 1; j <= wires_map.Extent(); j++)
    {
        if (!wires_map(j).IsSame(outer_wire))
        {
            inner_wires.push_back(TopoDS::Wire(wires_map(j)));
        }
    }

    std::vector<std::vector<Standard_Real>> parameter;
    std::vector<std::vector<Standard_Real>> parameter2;
    std::vector<Handle(Geom2d_Curve)> p_curve1;
    std::vector<Handle(Geom2d_Curve)> p_curve2;
    TopExp_Explorer edge_exp;
    Standard_Boolean flag;
    for (edge_exp.Init(outer_wire, TopAbs_EDGE); edge_exp.More(); edge_exp.Next()) {
        TopoDS_Edge edge = TopoDS::Edge(edge_exp.Current().Composed(outer_wire.Orientation()));
        Standard_Real first;
        Standard_Real last;
        Handle(Geom2d_Curve) my_handle = BRep_Tool::CurveOnSurface(edge, faceo, first, last, &flag);
        parameter.push_back(std::vector<Standard_Real>{first, last});
        p_curve1.push_back(my_handle);
    }

    for (auto inwire : inner_wires) {
        TopExp_Explorer edge_exp2;
        Standard_Boolean flag2;
        for (edge_exp2.Init(inwire, TopAbs_EDGE); edge_exp2.More(); edge_exp2.Next()) {
            TopoDS_Edge edge = TopoDS::Edge(edge_exp2.Current().Composed(inwire.Orientation()));
            Standard_Real first;
            Standard_Real last;
            p_curve2.push_back(BRep_Tool::CurveOnSurface(edge, faceo, first, last, &flag2));
            parameter2.push_back(std::vector<Standard_Real>{first, last});
        }
    }

    BRepBuilderAPI_MakeWire mkWire;
    int i = 0;
    for (auto a : p_curve1) {
        TopoDS_Edge anEdge = BRepBuilderAPI_MakeEdge(a, h_bsurface, parameter[i][0], parameter[i][1]);
        i++;
        //vout << anEdge;
        mkWire.Add(anEdge);
    }

    TopoDS_Wire new_wire = mkWire.Wire();
    BRepBuilderAPI_MakeFace faceMaker(h_bsurface, new_wire, false);
    new_wire.Reverse();
    if (p_curve2.size() != 0) {
        BRepBuilderAPI_MakeWire mkWire2;
        for (int j = 0; j < p_curve2.size(); j++) {
            TopoDS_Edge anEdge = BRepBuilderAPI_MakeEdge(p_curve2[j], h_bsurface, parameter2[j][0], parameter2[j][1]);
            mkWire2.Add(anEdge);
        }
        TopoDS_Wire new_wire2 = mkWire2.Wire();
        faceMaker.Add(new_wire2);
    }
    ShapeFix_Face fix(faceMaker.Face());
    fix.SetPrecision(1e-7);
    fix.Perform();
    if (fix.Status(ShapeExtend_OK))
        cout << "ShapeExtend_OK ";
    else if (fix.Status(ShapeExtend_DONE1))
        cout << "ShapeExtend_DONE1";
    else if (fix.Status(ShapeExtend_DONE2))
        cout << "ShapeExtend_DONE2";
    else if (fix.Status(ShapeExtend_DONE3))
        cout << "ShapeExtend_DONE3";
    else if (fix.Status(ShapeExtend_DONE4))
        cout << "ShapeExtend_DONE4";
    else if (fix.Status(ShapeExtend_DONE5))
        cout << "ShapeExtend_DONE5";
    else if (fix.Status(ShapeExtend_DONE6))
        cout << "ShapeExtend_DONE6";
    else if (fix.Status(ShapeExtend_DONE7))
        cout << "ShapeExtend_DONE7";
    else if (fix.Status(ShapeExtend_DONE8))
        cout << "ShapeExtend_DONE8";
    else if (fix.Status(ShapeExtend_DONE))
        cout << "ShapeExtend_DONE ";
    else if (fix.Status(ShapeExtend_FAIL1))
        cout << "ShapeExtend_FAIL1 ";
    else if (fix.Status(ShapeExtend_FAIL2))
        cout << "ShapeExtend_FAIL2 ";
    else if (fix.Status(ShapeExtend_FAIL3))
        cout << "ShapeExtend_FAIL3 ";
    else if (fix.Status(ShapeExtend_FAIL4))
        cout << "ShapeExtend_FAIL4 ";
    else if (fix.Status(ShapeExtend_FAIL5))
        cout << "ShapeExtend_FAIL5 ";
    else if (fix.Status(ShapeExtend_FAIL6))
        cout << "ShapeExtend_FAIL6 ";
    else if (fix.Status(ShapeExtend_FAIL7))
        cout << "ShapeExtend_FAIL7 ";
    else if (fix.Status(ShapeExtend_FAIL8))
        cout << "ShapeExtend_FAIL8 ";
    else if (fix.Status(ShapeExtend_FAIL))
        cout << "ShapeExtend_FAIL ";


    vout << fix.Face();

    vout.StartMessageLoop();
   
}

 

[Quaoar]

This is clearly the orientation problem of the resulting wire: it becomes a gap in a topologically untrimmed (sort of) surface:



ShapeFix does not solve this problem, as sometimes you might want to model such faces intentionally (like to untrim them forcibly). It should be noted that `face_shape` as returned by the NURBS converter is still Okay, so corruption happens later on. What is the idea behind this code after conversion? Why do you have to recompose the contours?