// Given sin and cos of max angle between normals calculate whether f0 and f1
// on celli make larger angle. Uses sinAngle only for quadrant detection.
bool largerAngle
(
const primitiveMesh& mesh,
const scalar cosAngle,
const scalar sinAngle,
const label celli,
const label f0, // face label
const label f1,
const vector& n0, // normal at f0
const vector& n1
)
{
const labelList& own = mesh.faceOwner();
bool sameFaceOrder = !((own[f0] == celli) ^ (own[f1] == celli));
// Get cos between faceArea vectors. Correct so flat angle (180 degrees)
// gives -1.
scalar normalCosAngle = n0 & n1;
if (sameFaceOrder)
{
normalCosAngle = -normalCosAngle;
}
// Get cos between faceCentre and normal vector to determine in
// which quadrant angle is. (Is correct for unwarped faces only!)
// Correct for non-outwards pointing normal.
vector c1c0(mesh.faceCentres()[f1] - mesh.faceCentres()[f0]);
c1c0 /= mag(c1c0) + VSMALL;
scalar fcCosAngle = n0 & c1c0;
if (own[f0] != celli)
{
fcCosAngle = -fcCosAngle;
}
if (sinAngle < 0.0)
{
// Looking for concave angles (quadrant 3 or 4)
if (fcCosAngle <= 0)
{
// Angle is convex so smaller.
return false;
}
else
{
if (normalCosAngle < cosAngle)
{
return false;
}
else
{
return true;
}
}
}
else
{
// Looking for convex angles (quadrant 1 or 2)
if (fcCosAngle > 0)
{
// Concave angle
return true;
}
else
{
// Convex. Check cos of normal vectors.
if (normalCosAngle > cosAngle)
{
return false;
}
else
{
return true;
}
}
}
}
