161 lines
4.5 KiB
C
161 lines
4.5 KiB
C
/*---------------------------------------------------------------------------*\
|
|
========= |
|
|
\\ / F ield | OpenFOAM: The Open Source CFD Toolbox
|
|
\\ / O peration |
|
|
\\ / A nd | Copyright held by original author
|
|
\\/ 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 2 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, write to the Free Software Foundation,
|
|
Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
|
|
|
|
\*---------------------------------------------------------------------------*/
|
|
|
|
#include "collapseEdge.H"
|
|
|
|
//- Sets point neighbours of face to val
|
|
static void markPointNbrs
|
|
(
|
|
const triSurface& surf,
|
|
const label faceI,
|
|
const bool val,
|
|
boolList& okToCollapse
|
|
)
|
|
{
|
|
const labelledTri& 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 labelledTri& f = localFaces[faceI];
|
|
|
|
forAll(f, fp)
|
|
{
|
|
label v = f[fp];
|
|
label v1 = f[(fp+1) % 3];
|
|
|
|
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;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
Pout<< "collapseEdge : collapsing " << nCollapsed << " triangles"
|
|
<< 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;
|
|
}
|
|
|
|
|
|
// ************************************************************************* //
|