double PointInPolygon::angle( const Point2D& p, const Point2D& q, const Point2D& r )
{
Vector2D<double> u = p - q;
Vector2D<double> v = r - q;
// return atan2( u % v, u * v );
double ang1 = pseudoAngle( u );
double ang2 = pseudoAngle( v );
double ang = fabs( ang1 - ang2 );
ang = ang > 4.0 ? 8 - ang : ang;
int sinal = u % v > 0 ? 1 : -1;
return sinal * ang;
}
Foam::labelListList
Foam::PatchTools::sortedEdgeFaces
(
const PrimitivePatch<Face, FaceList, PointField, PointType>& p
)
{
const edgeList& edges = p.edges();
const labelListList& edgeFaces = p.edgeFaces();
const List<Face>& localFaces = p.localFaces();
const Field<PointType>& localPoints = p.localPoints();
// create the lists for the various results. (resized on completion)
labelListList sortedEdgeFaces = labelListList(edgeFaces.size());
forAll(edgeFaces, edgeI)
{
const labelList& faceNbs = edgeFaces[edgeI];
if (faceNbs.size() > 2)
{
// Get point on edge and normalized direction of edge (= e2 base
// of our coordinate system)
const edge& e = edges[edgeI];
const point& edgePt = localPoints[e.start()];
vector e2 = e.vec(localPoints);
e2 /= mag(e2) + VSMALL;
// Get opposite vertex for 0th face
const Face& f = localFaces[faceNbs[0]];
label fp0 = findIndex(f, e[0]);
label fp1 = f.fcIndex(fp0);
label vertI = (f[fp1] != e[1] ? f[fp1] : f.fcIndex(fp1));
// Get vector normal both to e2 and to edge from opposite vertex
// to edge (will be x-axis of our coordinate system)
vector e0 = e2 ^ (localPoints[vertI] - edgePt);
e0 /= mag(e0) + VSMALL;
// Get y-axis of coordinate system
vector e1 = e2 ^ e0;
SortableList<scalar> faceAngles(faceNbs.size());
// e0 is reference so angle is 0
faceAngles[0] = 0;
for (label nbI = 1; nbI < faceNbs.size(); nbI++)
{
// Get opposite vertex
const Face& f = localFaces[faceNbs[nbI]];
label fp0 = findIndex(f, e[0]);
label fp1 = f.fcIndex(fp0);
label vertI = (f[fp1] != e[1] ? f[fp1] : f.fcIndex(fp1));
vector vec = e2 ^ (localPoints[vertI] - edgePt);
vec /= mag(vec) + VSMALL;
faceAngles[nbI] = pseudoAngle
(
e0,
e1,
vec
);
}
faceAngles.sort();
sortedEdgeFaces[edgeI] = UIndirectList<label>
(
faceNbs,
faceAngles.indices()
);
}
else
{
// No need to sort. Just copy.
sortedEdgeFaces[edgeI] = faceNbs;
}
}
return sortedEdgeFaces;
}
