collapseEdge.C
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1/*---------------------------------------------------------------------------*\
2 ========= |
3 \\ / F ield | OpenFOAM: The Open Source CFD Toolbox
4 \\ / O peration |
5 \\ / A nd | www.openfoam.com
6 \\/ M anipulation |
7-------------------------------------------------------------------------------
8 Copyright (C) 2011-2016 OpenFOAM Foundation
9 Copyright (C) 2020-2022 OpenCFD Ltd.
10-------------------------------------------------------------------------------
11License
12 This file is part of OpenFOAM.
13
14 OpenFOAM is free software: you can redistribute it and/or modify it
15 under the terms of the GNU General Public License as published by
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21 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
22 for more details.
23
24 You should have received a copy of the GNU General Public License
25 along with OpenFOAM. If not, see <http://www.gnu.org/licenses/>.
26
27\*---------------------------------------------------------------------------*/
28
29#include "collapseEdge.H"
30
31static void markPointNbrs
32(
33 const triSurface& surf,
34 const label facei,
35 const bool val,
36 boolList& okToCollapse
37)
38{
39 const triSurface::face_type& f = surf.localFaces()[facei];
40
41 forAll(f, fp)
42 {
43 const labelList& pFaces = surf.pointFaces()[f[fp]];
44
45 forAll(pFaces, i)
46 {
47 okToCollapse[pFaces[i]] = false;
48 }
49 }
50}
51
52
53static triSurface pack
54(
55 const triSurface& surf,
56 const pointField& localPoints,
57 const labelList& pointMap
58)
59{
60 List<labelledTri> newTriangles(surf.size());
61 label nNewTris = 0;
62
63 // Iterate and work on a copy
64 for (labelledTri f : surf.localFaces())
65 {
66 // inplace renumber
67 f[0] = pointMap[f[0]];
68 f[1] = pointMap[f[1]];
69 f[2] = pointMap[f[2]];
70
71 if (f.valid())
72 {
73 newTriangles[nNewTris++] = f;
74 }
75 }
76 newTriangles.resize(nNewTris);
77
78 return triSurface(newTriangles, surf.patches(), localPoints);
79}
80
81
82// Collapses small edge to point, thus removing triangle.
83label collapseEdge(triSurface& surf, const scalar minLen)
84{
85 label nTotalCollapsed = 0;
86
87 while (true)
88 {
89 const pointField& localPoints = surf.localPoints();
90 const List<labelledTri>& localFaces = surf.localFaces();
91
92
93 // Mapping from old to new points
94 labelList pointMap(identity(surf.nPoints()));
95
96 // Storage for new points.
97 pointField newPoints(localPoints);
98
99 // To protect neighbours of collapsed faces.
100 boolList okToCollapse(surf.size(), true);
101 label nCollapsed = 0;
102
103 forAll(localFaces, facei)
104 {
105 if (okToCollapse[facei])
106 {
107 // Check edge lengths.
108 const triSurface::face_type& f = localFaces[facei];
109
110 forAll(f, fp)
111 {
112 label v = f[fp];
113 label v1 = f[f.fcIndex(fp)];
114
115 if (mag(localPoints[v1] - localPoints[v]) < minLen)
116 {
117 // Collapse f[fp1] onto f[fp].
118 pointMap[v1] = v;
119 newPoints[v] = 0.5*(localPoints[v1] + localPoints[v]);
120
121 //Pout<< "Collapsing triangle " << facei
122 // << " to edge mid " << newPoints[v] << endl;
123
124 nCollapsed++;
125 okToCollapse[facei] = false;
126
127 // Protect point neighbours from collapsing.
128 markPointNbrs(surf, facei, false, okToCollapse);
129
130 break;
131 }
132 }
133 }
134 }
135
136 Info<< "collapseEdge : collapsing " << nCollapsed
137 << " triangles to a single edge."
138 << endl;
139
140 nTotalCollapsed += nCollapsed;
141
142 if (nCollapsed == 0)
143 {
144 break;
145 }
146
147 // Pack the triangles
148 surf = pack(surf, newPoints, pointMap);
149 }
150
151 // Remove any unused vertices
152 surf = triSurface(surf.localFaces(), surf.patches(), surf.localPoints());
153
154 return nTotalCollapsed;
155}
156
157
158// ************************************************************************* //
Routines to collapse small edges.
label collapseEdge(triSurface &surf, const scalar minLen)
Keep collapsing all edges < minLen.
labelList identity(const label len, label start=0)
Return an identity map of the given length with (map[i] == i)
Definition: labelList.C:38
List< label > labelList
A List of labels.
Definition: List.H:66
messageStream Info
Information stream (stdout output on master, null elsewhere)
vectorField pointField
pointField is a vectorField.
Definition: pointFieldFwd.H:44
Ostream & endl(Ostream &os)
Add newline and flush stream.
Definition: Ostream.H:372
dimensioned< typename typeOfMag< Type >::type > mag(const dimensioned< Type > &dt)
List< bool > boolList
A List of bools.
Definition: List.H:64
Info<< "Finished reading KIVA file"<< endl;cellShapeList cellShapes(nPoints);labelList cellZoning(nPoints, -1);const cellModel &hex=cellModel::ref(cellModel::HEX);labelList hexLabels(8);label activeCells=0;labelList pointMap(nPoints);forAll(pointMap, i){ pointMap[i]=i;}for(label i=0;i< nPoints;i++){ if(f[i] > 0.0) { hexLabels[0]=i;hexLabels[1]=i1tab[i];hexLabels[2]=i3tab[i1tab[i]];hexLabels[3]=i3tab[i];hexLabels[4]=i8tab[i];hexLabels[5]=i1tab[i8tab[i]];hexLabels[6]=i3tab[i1tab[i8tab[i]]];hexLabels[7]=i3tab[i8tab[i]];cellShapes[activeCells].reset(hex, hexLabels);edgeList edges=cellShapes[activeCells].edges();forAll(edges, ei) { if(edges[ei].mag(points)< SMALL) { label start=pointMap[edges[ei].start()];while(start !=pointMap[start]) { start=pointMap[start];} label end=pointMap[edges[ei].end()];while(end !=pointMap[end]) { end=pointMap[end];} label minLabel=min(start, end);pointMap[start]=pointMap[end]=minLabel;} } cellZoning[activeCells]=idreg[i];activeCells++;}}cellShapes.setSize(activeCells);cellZoning.setSize(activeCells);forAll(cellShapes, celli){ cellShape &cs=cellShapes[celli];forAll(cs, i) { cs[i]=pointMap[cs[i]];} cs.collapse();}label bcIDs[11]={-1, 0, 2, 4, -1, 5, -1, 6, 7, 8, 9};const label nBCs=12;const word *kivaPatchTypes[nBCs]={ &wallPolyPatch::typeName, &wallPolyPatch::typeName, &wallPolyPatch::typeName, &wallPolyPatch::typeName, &symmetryPolyPatch::typeName, &wedgePolyPatch::typeName, &polyPatch::typeName, &polyPatch::typeName, &polyPatch::typeName, &polyPatch::typeName, &symmetryPolyPatch::typeName, &oldCyclicPolyPatch::typeName};enum patchTypeNames{ PISTON, VALVE, LINER, CYLINDERHEAD, AXIS, WEDGE, INFLOW, OUTFLOW, PRESIN, PRESOUT, SYMMETRYPLANE, CYCLIC};const char *kivaPatchNames[nBCs]={ "piston", "valve", "liner", "cylinderHead", "axis", "wedge", "inflow", "outflow", "presin", "presout", "symmetryPlane", "cyclic"};List< SLList< face > > pFaces[nBCs]
Definition: readKivaGrid.H:235
labelList f(nPoints)
#define forAll(list, i)
Loop across all elements in list.
Definition: stdFoam.H:333