dung-han-lee / convexhull-3d-implementation-of-incremental-convexhull-algorithm Goto Github PK

I have some trouble with "warning: property violated!"

I forked your repo so I could try to improve some things. I used commit milasudril@374f76e

I get an error when trying to compute the convex hull of the attached point cloud.
mesh.obj.gz

int MinimumZoneFitPlane(const Point* pointsIn, int lengthIn, PlaneKernel* outLseg)
{
ConvexHull hull(pointsIn, lengthIn);
std::list faces = hull.GetFaces();
std::vector vertexs = hull.GetVertices();
std::vector pointT(vertexs.size());
for (int i = 0; i < vertexs.size(); i++) {
pointT[i].x = vertexs[i].x;
pointT[i].y = vertexs[i].y;
pointT[i].z = vertexs[i].z;
}

std::string filePath = "D:/CMM/PlanePointsVertex.csv";
WritePointsCSV(pointT.data(), pointT.size(), filePath.c_str());

return Geom3DError::OK;

}
The above is the call code for computing the 3D convex hull, the result is not correct;
PlanePoints.csv

In case you have a hash collision when computing the hash of the pair of points, you will overwrite existing entries. Instead of using the hash as a key, you should use the actual pair, and use an associated hash function, ie:

    struct PointHash
    {
      size_t operator()(Point3D a) const
      {
        return std::hash<double>{}(a.x) ^ std::hash<double>{}(a.y) ^ std::hash<double>{}(a.z);
      }
    };

    struct EdgeEndpoints
    {
      Point3D p1;
      Point3D p2;

      constexpr bool operator==(const EdgeEndpoints&) const = default;
      constexpr bool operator!=(const EdgeEndpoints&) const = default;
    };

    struct EdgeEndpointHash
    {
      size_t operator()(EdgeEndpoints const& a) const
      {
        return PointHash{}(a.p1) ^ PointHash{}(a.p2);
      }
    };

    std::unordered_map<EdgeEndpoints, Edge*, EdgeEndpointHash> map_edges;

Also, please do not convert to string when computing hashes.

It is not recommended to compare floating point numbers with ==