static bool SealSeam(int closed_dir, ON_BrepFace& F)
{
if (closed_dir) closed_dir = 1;
int seam_dir = 1-closed_dir;
ON_Brep* pBrep = F.Brep();
if (!pBrep) return false;
const ON_Surface* pSrf = F.SurfaceOf();
if (!pSrf || !pSrf->IsClosed(closed_dir)) return false;
ON_Surface::ISO isoA = ON_Surface::not_iso;//same dir as isocurve
ON_Surface::ISO isoB = ON_Surface::not_iso;//opposite dir as isocurve
if (closed_dir){
isoA = ON_Surface::S_iso;
isoB = ON_Surface::N_iso;
}
else {
isoA = ON_Surface::E_iso;
isoB = ON_Surface::W_iso;
}
/* TODO: Handle cases where there is more than one trim on a seam side
or seam edges do not fully overlap.
*/
//Look for a single pair of trims that match across parameter space.
int A_id = -1;
int B_id = -1;
int li;
for (li=0; li<F.m_li.Count(); li++){
const ON_BrepLoop* L = F.Loop(li);
if (!L || L->m_type != ON_BrepLoop::outer) continue;
int lti;
for (lti = 0; lti<L->m_ti.Count(); lti++ ){
ON_BrepTrim* T = L->Trim(lti);
if (!T) continue;
if (T->m_iso == isoA) {
if (A_id >= 0)
return false;
A_id = T->m_trim_index;
}
else if (T->m_iso == isoB) {
if (B_id >= 0)
return false;
B_id = T->m_trim_index;
}
}
}
if (A_id < 0 || B_id < 0)
return true;//no seam to join
ON_BrepTrim& TA = pBrep->m_T[A_id];
ON_BrepTrim& TB = pBrep->m_T[B_id];
ON_BrepEdge* pEA = TA.Edge();
ON_BrepEdge* pEB = TB.Edge();
if (!pEA || !pEB)
return false;
ON_Interval a,b;
int i;
for (i=0; i<2; i++){
a[i] = TA.PointAt(TA.Domain()[i])[seam_dir];
b[i] = TB.PointAt(TB.Domain()[i])[seam_dir];
}
a.MakeIncreasing();
b.MakeIncreasing();
if (a[0] >= b[1] || b[0] >= a[1])
return true; //nothing to be joined;
double pspace_tol = 1.0e-8;
if (a.Length() < 10.0*pspace_tol)
return false;
if (fabs(a[0] - b[0]) > pspace_tol || fabs(a[1] - b[1]) > pspace_tol)
return false;
//fix vertices so join will work.
RebuildVertexToTrimEnd(TA, 0);
RebuildVertexToTrimEnd(TA, 1);
RebuildVertexToTrimEnd(TB, 0);
RebuildVertexToTrimEnd(TB, 1);
double join_tol = 1.0e-6;
if (!pBrep->JoinEdges(*pEA, *pEB, join_tol))
return false;
TA.m_type = ON_BrepTrim::seam;
TB.m_type = ON_BrepTrim::seam;
return true;
}
