Add the OpenFOAM source tree

applications/utilities/surface/surfaceClean/collapseEdge.C

@@ -0,0 +1,161 @@
+/*---------------------------------------------------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     |
+    \\  /    A nd           | Copyright (C) 2011 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"
+
+//- Sets point neighbours of face to val
+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;
+}
+
+
+// ************************************************************************* //