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/*---------------------------------------------------------------------------*\
========= |
\\ / F ield | OpenFOAM: The Open Source CFD Toolbox
\\ / O peration |
\\ / A nd | Copyright (C) 2011-2016 OpenFOAM Foundation
\\/ M anipulation |
-------------------------------------------------------------------------------
License
This file is part of OpenFOAM.
OpenFOAM is free software: you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
OpenFOAM is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
for more details.
You should have received a copy of the GNU General Public License
along with OpenFOAM. If not, see <http://www.gnu.org/licenses/>.
\*---------------------------------------------------------------------------*/
#include "collapseEdge.H"
static void markPointNbrs
(
const triSurface& surf,
const label facei,
const bool val,
boolList& okToCollapse
)
{
const triSurface::FaceType& f = surf.localFaces()[facei];
forAll(f, fp)
{
const labelList& pFaces = surf.pointFaces()[f[fp]];
forAll(pFaces, i)
{
okToCollapse[pFaces[i]] = false;
}
}
}
static triSurface pack
(
const triSurface& surf,
const pointField& localPoints,
const labelList& pointMap
)
{
List<labelledTri> newTriangles(surf.size());
label newTriangleI = 0;
forAll(surf, facei)
{
const labelledTri& f = surf.localFaces()[facei];
label newA = pointMap[f[0]];
label newB = pointMap[f[1]];
label newC = pointMap[f[2]];
if ((newA != newB) && (newA != newC) && (newB != newC))
{
newTriangles[newTriangleI++] =
labelledTri(newA, newB, newC, f.region());
}
}
newTriangles.setSize(newTriangleI);
return triSurface(newTriangles, surf.patches(), localPoints);
}
// Collapses small edge to point, thus removing triangle.
label collapseEdge(triSurface& surf, const scalar minLen)
{
label nTotalCollapsed = 0;
while (true)
{
const pointField& localPoints = surf.localPoints();
const List<labelledTri>& localFaces = surf.localFaces();
// Mapping from old to new points
labelList pointMap(surf.nPoints());
forAll(pointMap, i)
{
pointMap[i] = i;
}
// Storage for new points.
pointField newPoints(localPoints);
// To protect neighbours of collapsed faces.
boolList okToCollapse(surf.size(), true);
label nCollapsed = 0;
forAll(localFaces, facei)
{
if (okToCollapse[facei])
{
// Check edge lengths.
const triSurface::FaceType& f = localFaces[facei];
forAll(f, fp)
{
label v = f[fp];
label v1 = f[f.fcIndex(fp)];
if (mag(localPoints[v1] - localPoints[v]) < minLen)
{
// Collapse f[fp1] onto f[fp].
pointMap[v1] = v;
newPoints[v] = 0.5*(localPoints[v1] + localPoints[v]);
//Pout<< "Collapsing triange " << facei
// << " to edge mid " << newPoints[v] << endl;
nCollapsed++;
okToCollapse[facei] = false;
// Protect point neighbours from collapsing.
markPointNbrs(surf, facei, false, okToCollapse);
break;
}
}
}
}
Info<< "collapseEdge : collapsing " << nCollapsed
<< " triangles to a single edge."
<< endl;
nTotalCollapsed += nCollapsed;
if (nCollapsed == 0)
{
break;
}
// Pack the triangles
surf = pack(surf, newPoints, pointMap);
}
// Remove any unused vertices
surf = triSurface(surf.localFaces(), surf.patches(), surf.localPoints());
return nTotalCollapsed;
}
// ************************************************************************* //
|
