NEM::GEO::convexContainer Class Reference

An implementation of convex container object for point The class implements methods to generate a convex hull for a point cloud, perform point location, and output to STL format. More...

Detailed Description

Note

Only use for convex objects.

Definition at line 113 of file convexContainer.H.

Public Member Functions
	convexContainer ()
	default constructor More...
	convexContainer (std::vector< std::vector< double > > &verts)
	construct from a vector point coordinates More...
	convexContainer (std::vector< quickhull::Vector3< double > > &verts)
virtual	~convexContainer ()
virtual void	setVertex (std::vector< std::vector< double > > &verts)
	re-/setting vertice coordinates More...
virtual void	computeConvexHull ()
	calculating the convex hull More...
bool	isInConvexPoly (NEM::MTH::Vector const &p)
	check for point containment More...
bool	isInConvexPoly (const std::vector< double > &p)
void	toSTL (std::string file_name) const
	generate STL triangulation from the convex hull More...

Private Attributes
bool	_isReady
std::vector< quickhull::Vector3< double > >	vrts
quickhull::QuickHull< double > *	qHull
std::vector< Face >	fv

Constructor & Destructor Documentation

convexContainer() [1/3]

NEM::GEO::convexContainer::convexContainer

(

)

Definition at line 38 of file convexContainer.C.

                                :
    _isReady(false)
{}

convexContainer() [2/3]

NEM::GEO::convexContainer::convexContainer

(

std::vector< std::vector< double > > &

verts

)

Parameters

verts

vector of vector of doubles of point coordinats

Definition at line 43 of file convexContainer.C.

References setVertex().

{
    // deep copying
    setVertex(inVrts);
}

convexContainer() [3/3]

NEM::GEO::convexContainer::convexContainer

(

std::vector< quickhull::Vector3< double > > &

verts

)

Definition at line 49 of file convexContainer.C.

References vrts.

{
    // deep copying
    for (auto itr=inVrts.begin(); itr!=inVrts.end(); itr++)
        vrts.emplace_back(*itr);
}

~convexContainer()

virtual NEM::GEO::convexContainer::~convexContainer ( )

inlinevirtual

Definition at line 127 of file convexContainer.H.

{};

Member Function Documentation

computeConvexHull()

void NEM::GEO::convexContainer::computeConvexHull ( )

virtual

Definition at line 63 of file convexContainer.C.

References _isReady, fv, qHull, NEM::GEO::Face::v, vrts, NEM::MTH::Vector::x, NEM::MTH::Vector::y, and NEM::MTH::Vector::z.

Referenced by isInConvexPoly().

{
    // computes/re-computes convex hull of the verices
    std::vector<size_t> indxBuf;
    quickhull::VertexDataSource<double> vrtBuf;
    qHull = new quickhull::QuickHull<double>();
    auto hull = qHull->getConvexHull(vrts, false, false, 1.e-14);
    indxBuf = hull.getIndexBuffer();
    vrtBuf = hull.getVertexBuffer();

    // converting to face-vector format
    //std::cout << "Size of index buffer = "
    //    << indxBuf.size() << std::endl;

    // saving to vf
    for (int it=0; it<indxBuf.size(); it+=3)
    {
        Face f;
        for (int idx=0; idx<3; idx++)
        {
            NEM::MTH::Vector pnt;
            pnt.x = (vrtBuf[indxBuf[it+idx]]).x;
            pnt.y = (vrtBuf[indxBuf[it+idx]]).y;
            pnt.z = (vrtBuf[indxBuf[it+idx]]).z;
            f.v.push_back(pnt);
        }
        fv.push_back(f);
    }

    _isReady = true;

}

isInConvexPoly() [1/2]

bool NEM::GEO::convexContainer::isInConvexPoly

(

NEM::MTH::Vector const &

p

)

Parameters

p	vector of coordinates of the point

Definition at line 96 of file convexContainer.C.

References _isReady, computeConvexHull(), NEM::MTH::Vector::dot(), fv, and NEM::MTH::Vector::norm().

Referenced by isInConvexPoly().

                                                          {
    // check readiness
    if (!_isReady)
        computeConvexHull();

    // looping through faces
    for (Face const& f : fv) {
        NEM::MTH::Vector p2f = f.v[0] - p;         // f.v[0] is an arbitrary point on f
        double d = p2f.dot(f.normal());
        d /= p2f.norm();                 // for numeric stability

        constexpr double bound = -1e-15; // use 1e15 to exclude boundaries
        if (d < bound)
          return false;
    }
    return true;
}

isInConvexPoly() [2/2]

bool NEM::GEO::convexContainer::isInConvexPoly

(

const std::vector< double > &

p

)

Definition at line 114 of file convexContainer.C.

References isInConvexPoly(), NEM::MTH::Vector::x, NEM::MTH::Vector::y, and NEM::MTH::Vector::z.

                                                               {
    if (p.size() != 3)
        throw;
    NEM::MTH::Vector pnt;
    pnt.x = p[0];
    pnt.y = p[1];
    pnt.z = p[2];
    return(isInConvexPoly(pnt));
}

setVertex()

void NEM::GEO::convexContainer::setVertex ( std::vector< std::vector< double > > &  verts )

virtual

Parameters

verts

vector of vector of doubles of point coordinats

Definition at line 56 of file convexContainer.C.

References vrts.

Referenced by convexContainer().

{
    // deep copying
    for (auto itr=inVrts.begin(); itr!=inVrts.end(); itr++)
        vrts.emplace_back((*itr)[0], (*itr)[1], (*itr)[2]);
}

toSTL()

void NEM::GEO::convexContainer::toSTL

(

std::string

file_name

)

const

Parameters

file_name

full path to the output STL file

Definition at line 124 of file convexContainer.C.

References fv, NEM::MTH::Vector::x, NEM::MTH::Vector::y, and NEM::MTH::Vector::z.

                                                      {

    //ascii file
    std::ofstream myfile;
    myfile.open((file_name + ".stl").c_str(),  std::ios::out | std::ios::binary);
    myfile << "solid "
           << file_name
           << "\n";

    //write down every triangle
    for (auto it = fv.begin(); it!=fv.end(); it++){

        //normal vector coordinates
        NEM::MTH::Vector n = it->normal();
        myfile << "facet normal ";
        myfile << n.x << " " << n.y << " " << n.z << "\n";

        myfile << "\touter loop\n";
        //vertex coordinates
        for (int iv=0; iv<3; iv++)
        {
            myfile << "\t\tvertex "
                   << (it->v[iv]).x << " "
                   << (it->v[iv]).y << " "
                   << (it->v[iv]).z << "\n";
        }
        myfile << "\tendloop\n";
        myfile << "endfacet\n";
    }
    myfile << "endsolid " << file_name << "\n";
    myfile.close();

}

Member Data Documentation

_isReady

bool NEM::GEO::convexContainer::_isReady

private

Definition at line 153 of file convexContainer.H.

Referenced by computeConvexHull(), and isInConvexPoly().

fv

std::vector<Face> NEM::GEO::convexContainer::fv

private

Definition at line 156 of file convexContainer.H.

Referenced by computeConvexHull(), isInConvexPoly(), and toSTL().

qHull

quickhull::QuickHull<double>* NEM::GEO::convexContainer::qHull

private

Definition at line 155 of file convexContainer.H.

Referenced by computeConvexHull().

vrts

std::vector<quickhull::Vector3<double> > NEM::GEO::convexContainer::vrts

private

Definition at line 154 of file convexContainer.H.

Referenced by computeConvexHull(), convexContainer(), and setVertex().

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The documentation for this class was generated from the following files:

• convexContainer.H
• convexContainer.C