src/edgeMesh/edgeMesh.C

   1 /*---------------------------------------------------------------------------*\
   2   =========                 |
   3   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
   4    \\    /   O peration     |
   5     \\  /    A nd           | Copyright (C) 1991-2008 OpenCFD Ltd.
   6      \\/     M anipulation  |
   7 -------------------------------------------------------------------------------
   8 License
   9     This file is part of OpenFOAM.
  10
  11     OpenFOAM is free software; you can redistribute it and/or modify it
  12     under the terms of the GNU General Public License as published by the
  13     Free Software Foundation; either version 2 of the License, or (at your
  14     option) any later version.
  15
  16     OpenFOAM is distributed in the hope that it will be useful, but WITHOUT
  17     ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  18     FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  19     for more details.
  20
  21     You should have received a copy of the GNU General Public License
  22     along with OpenFOAM; if not, write to the Free Software Foundation,
  23     Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
  24
  25 \*---------------------------------------------------------------------------*/
  26
  27 #include "edgeMesh.H"
  28 #include "mergePoints.H"
  29 #include "StaticHashTable.H"
  30
  31 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
  32
  33 namespace Foam
  34 {
  35
  36 // * * * * * * * * * * * * * Private Member Functions  * * * * * * * * * * * //
  37
  38 void edgeMesh::calcPointEdges() const
  39 {
  40     if (pointEdgesPtr_.valid())
  41     {
  42         FatalErrorIn("edgeMesh::calcPointEdges() const")
  43             << "pointEdges already calculated." << abort(FatalError);
  44     }
  45
  46     pointEdgesPtr_.reset(new labelListList(points_.size()));
  47     labelListList& pointEdges = pointEdgesPtr_();
  48
  49     // Count
  50     labelList nEdgesPerPoint(points_.size(), 0);
  51
  52     forAll(edges_, edgeI)
  53     {
  54         const edge& e = edges_[edgeI];
  55
  56         nEdgesPerPoint[e[0]]++;
  57         nEdgesPerPoint[e[1]]++;
  58     }
  59
  60     // Size
  61     forAll(pointEdges, pointI)
  62     {
  63         pointEdges[pointI].setSize(nEdgesPerPoint[pointI]);
  64     }
  65
  66     // Fill
  67     nEdgesPerPoint = 0;
  68
  69     forAll(edges_, edgeI)
  70     {
  71         const edge& e = edges_[edgeI];
  72
  73         label p0 = e[0];
  74         pointEdges[p0][nEdgesPerPoint[p0]++] = edgeI;
  75         label p1 = e[1];
  76         pointEdges[p1][nEdgesPerPoint[p1]++] = edgeI;
  77     }
  78 }
  79
  80
  81 // * * * * * * * * * * * * * * * * Constructors  * * * * * * * * * * * * * * //
  82
  83 // construct from components
  84 edgeMesh::edgeMesh(const pointField& points, const edgeList& edges)
  85 :
  86     points_(points),
  87     edges_(edges)
  88 {}
  89
  90
  91 // construct as copy
  92 edgeMesh::edgeMesh(const edgeMesh& em)
  93 :
  94     points_(em.points_),
  95     edges_(em.edges_),
  96     pointEdgesPtr_(NULL)
  97 {}
  98
  99
 100 // * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //
 101
 102 label edgeMesh::regions(labelList& edgeRegion) const
 103 {
 104     edgeRegion.setSize(edges_.size());
 105     edgeRegion = -1;
 106
 107     label startEdgeI = 0;
 108
 109     label currentRegion = 0;
 110
 111     while (true)
 112     {
 113         while (startEdgeI < edges_.size() && edgeRegion[startEdgeI] != -1)
 114         {
 115             startEdgeI++;
 116         }
 117
 118         if (startEdgeI == edges_.size())
 119         {
 120             break;
 121         }
 122
 123         // Found edge that has not yet been assigned a region.
 124         // Mark connected region with currentRegion starting at startEdgeI.
 125
 126         edgeRegion[startEdgeI] = currentRegion;
 127         labelList edgesToVisit(1, startEdgeI);
 128
 129         while (edgesToVisit.size() > 0)
 130         {
 131             // neighbours of current edgesToVisit
 132             DynamicList<label> newEdgesToVisit(edgesToVisit.size());
 133
 134             // Mark all point connected edges with current region.
 135             forAll(edgesToVisit, i)
 136             {
 137                 label edgeI = edgesToVisit[i];
 138
 139                 // Mark connected edges
 140                 const edge& e = edges_[edgeI];
 141
 142                 forAll(e, fp)
 143                 {
 144                     const labelList& pEdges = pointEdges()[e[fp]];
 145
 146                     forAll(pEdges, pEdgeI)
 147                     {
 148                         label nbrEdgeI = pEdges[pEdgeI];
 149
 150                         if (edgeRegion[nbrEdgeI] == -1)
 151                         {
 152                             edgeRegion[nbrEdgeI] = currentRegion;
 153                             newEdgesToVisit.append(nbrEdgeI);
 154                         }
 155                     }
 156                 }
 157             }
 158
 159             edgesToVisit.transfer(newEdgesToVisit.shrink());
 160         }
 161
 162         currentRegion++;
 163     }
 164     return currentRegion;
 165 }
 166
 167
 168 void edgeMesh::mergePoints(const scalar mergeDist)
 169 {
 170     pointField newPoints;
 171     labelList pointMap;
 172
 173     bool hasMerged = Foam::mergePoints
 174     (
 175         points_,
 176         mergeDist,
 177         false,
 178         pointMap,
 179         newPoints,
 180         vector::zero
 181     );
 182
 183     if (hasMerged)
 184     {
 185         pointEdgesPtr_.clear();
 186
 187         points_.transfer(newPoints);
 188
 189         // Renumber and make sure e[0] < e[1] (not really nessecary)
 190         forAll(edges_, edgeI)
 191         {
 192             edge& e = edges_[edgeI];
 193
 194             label p0 = pointMap[e[0]];
 195             label p1 = pointMap[e[1]];
 196
 197             if (p0 < p1)
 198             {
 199                 e[0] = p0;
 200                 e[1] = p1;
 201             }
 202             else
 203             {
 204                 e[0] = p1;
 205                 e[1] = p0;
 206             }
 207         }
 208
 209         // Compact using a hashtable and commutative hash of edge.
 210         StaticHashTable<label, edge, Hash<edge> > edgeToLabel
 211         (
 212             2*edges_.size()
 213         );
 214
 215         label newEdgeI = 0;
 216
 217         forAll(edges_, edgeI)
 218         {
 219             const edge& e = edges_[edgeI];
 220
 221             if (e[0] != e[1])
 222             {
 223                 if (edgeToLabel.insert(e, newEdgeI))
 224                 {
 225                     newEdgeI++;
 226                 }
 227             }
 228         }
 229
 230         edges_.setSize(newEdgeI);
 231
 232         for
 233         (
 234             StaticHashTable<label, edge, Hash<edge> >::const_iterator iter =
 235                 edgeToLabel.begin();
 236             iter != edgeToLabel.end();
 237             ++iter
 238         )
 239         {
 240             edges_[iter()] = iter.key();
 241         }
 242     }
 243 }
 244
 245
 246 // * * * * * * * * * * * * * * * Member Operators  * * * * * * * * * * * * * //
 247
 248 void edgeMesh::operator=(const edgeMesh& rhs)
 249 {
 250     points_ = rhs.points_;
 251     edges_ = rhs.edges_;
 252     pointEdgesPtr_.reset(NULL);
 253 }
 254
 255
 256 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 257
 258 } // End namespace Foam
 259
 260 // ************************************************************************* //