IGL_INLINE void igl::copyleft::cgal::outer_facet(
const Eigen::PlainObjectBase<DerivedV> & V,
const Eigen::PlainObjectBase<DerivedF> & F,
const Eigen::PlainObjectBase<DerivedN> & N,
const Eigen::PlainObjectBase<DerivedI> & I,
IndexType & f,
bool & flipped) {
// Algorithm:
// Find an outer edge.
// Find the incident facet with the largest absolute X normal component.
// If there is a tie, keep the one with positive X component.
// If there is still a tie, pick the face with the larger signed index
// (flipped face has negative index).
typedef typename DerivedV::Scalar Scalar;
typedef typename DerivedV::Index Index;
const size_t INVALID = std::numeric_limits<size_t>::max();
Index v1,v2;
Eigen::Matrix<Index,Eigen::Dynamic,1> incident_faces;
outer_edge(V, F, I, v1, v2, incident_faces);
assert(incident_faces.size() > 0);
auto generic_fabs = [&](const Scalar& val) -> const Scalar {
if (val >= 0) return val;
else return -val;
};
Scalar max_nx = 0;
size_t outer_fid = INVALID;
const size_t num_incident_faces = incident_faces.size();
for (size_t i=0; i<num_incident_faces; i++)
{
const auto& fid = incident_faces(i);
const Scalar nx = N(fid, 0);
if (outer_fid == INVALID) {
max_nx = nx;
outer_fid = fid;
} else {
if (generic_fabs(nx) > generic_fabs(max_nx)) {
max_nx = nx;
outer_fid = fid;
} else if (nx == -max_nx && nx > 0) {
max_nx = nx;
outer_fid = fid;
} else if (nx == max_nx) {
if ((max_nx >= 0 && outer_fid < fid) ||
(max_nx < 0 && outer_fid > fid)) {
max_nx = nx;
outer_fid = fid;
}
}
}
}
assert(outer_fid != INVALID);
f = outer_fid;
flipped = max_nx < 0;
}
void Foam::CV2D::calcDual
(
point2DField& dualPoints,
faceList& dualFaces,
wordList& patchNames,
labelList& patchSizes,
EdgeMap<label>& mapEdgesRegion,
EdgeMap<label>& indirectPatchEdge
) const
{
// Dual points stored in triangle order.
dualPoints.setSize(number_of_faces());
label dualVerti = 0;
for
(
Triangulation::Finite_faces_iterator fit = finite_faces_begin();
fit != finite_faces_end();
++fit
)
{
if
(
fit->vertex(0)->internalOrBoundaryPoint()
|| fit->vertex(1)->internalOrBoundaryPoint()
|| fit->vertex(2)->internalOrBoundaryPoint()
)
{
fit->faceIndex() = dualVerti;
dualPoints[dualVerti++] = toPoint2D(circumcenter(fit));
}
else
{
fit->faceIndex() = -1;
}
}
dualPoints.setSize(dualVerti);
extractPatches(patchNames, patchSizes, mapEdgesRegion, indirectPatchEdge);
forAll(patchNames, patchi)
{
Info<< "Patch " << patchNames[patchi]
<< " has size " << patchSizes[patchi] << endl;
}
// Create dual faces
// ~~~~~~~~~~~~~~~~~
dualFaces.setSize(number_of_vertices());
label dualFacei = 0;
labelList faceVerts(maxNvert);
for
(
Triangulation::Finite_vertices_iterator vit = finite_vertices_begin();
vit != finite_vertices_end();
++vit
)
{
if (vit->internalOrBoundaryPoint())
{
Face_circulator fcStart = incident_faces(vit);
Face_circulator fc = fcStart;
label verti = 0;
do
{
if (!is_infinite(fc))
{
if (fc->faceIndex() < 0)
{
FatalErrorInFunction
<< "Dual face uses vertex defined by a triangle"
" defined by an external point"
<< exit(FatalError);
}
// Look up the index of the triangle
faceVerts[verti++] = fc->faceIndex();
}
} while (++fc != fcStart);
if (faceVerts.size() > 2)
{
dualFaces[dualFacei++] =
face(labelList::subList(faceVerts, verti));
}
else
{
Info<< "From triangle point:" << vit->index()
<< " coord:" << toPoint2D(vit->point())
<< " generated illegal dualFace:" << faceVerts
<< endl;
}
}
}
dualFaces.setSize(dualFacei);
}
void Foam::CV2D::writeFaces(const fileName& fName, bool internalOnly) const
{
Info<< "Writing dual faces to " << fName << nl << endl;
OFstream str(fName);
label dualVerti = 0;
for
(
Triangulation::Finite_faces_iterator fit = finite_faces_begin();
fit != finite_faces_end();
++fit
)
{
if
(
!internalOnly
|| (
fit->vertex(0)->internalOrBoundaryPoint()
|| fit->vertex(1)->internalOrBoundaryPoint()
|| fit->vertex(2)->internalOrBoundaryPoint()
)
)
{
fit->faceIndex() = dualVerti++;
meshTools::writeOBJ(str, toPoint3D(circumcenter(fit)));
}
else
{
fit->faceIndex() = -1;
}
}
for
(
Triangulation::Finite_vertices_iterator vit = finite_vertices_begin();
vit != finite_vertices_end();
++vit
)
{
if (!internalOnly || vit->internalOrBoundaryPoint())
{
Face_circulator fcStart = incident_faces(vit);
Face_circulator fc = fcStart;
str<< 'f';
do
{
if (!is_infinite(fc))
{
if (fc->faceIndex() < 0)
{
FatalErrorInFunction
<< "Dual face uses vertex defined by a triangle"
" defined by an external point"
<< exit(FatalError);
}
str<< ' ' << fc->faceIndex() + 1;
}
} while (++fc != fcStart);
str<< nl;
}
}
}
