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foam-extend4.1-coherent-io/applications/utilities/surface/surfaceSplitNonManifolds/surfaceSplitNonManifolds.C
2016-06-21 15:04:12 +02:00

981 lines
25 KiB
C++

/*---------------------------------------------------------------------------*\
========= |
\\ / F ield | foam-extend: Open Source CFD
\\ / O peration | Version: 4.0
\\ / A nd | Web: http://www.foam-extend.org
\\/ M anipulation | For copyright notice see file Copyright
-------------------------------------------------------------------------------
License
This file is part of foam-extend.
foam-extend 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.
foam-extend 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 foam-extend. If not, see <http://www.gnu.org/licenses/>.
Description
Takes multiply connected surface and tries to split surface at
multiply connected edges by duplicating points. Introduces concept of
- borderEdge. Edge with 4 faces connected to it.
- borderPoint. Point connected to exactly 2 borderEdges.
- borderLine. Connected list of borderEdges.
By duplicating borderPoints this will split 'borderLines'. As a
preprocessing step it can detect borderEdges without any borderPoints
and explicitly split these triangles.
The problems in this algorithm are:
- determining which two (of the four) faces form a surface. Done by walking
face-edge-face while keeping and edge or point on the borderEdge
borderPoint.
- determining the outwards pointing normal to be used to slightly offset the
duplicated point.
Uses sortedEdgeFaces quite a bit.
Is tested on simple borderLines resulting from extracting a surface
from a hex mesh. Will quite possibly go wrong on more complicated border
lines (i.e. ones forming a loop).
Dumps surface every so often since might take a long time to complete.
\*---------------------------------------------------------------------------*/
#include "argList.H"
#include "triSurface.H"
#include "OFstream.H"
#include "ListOps.H"
#include "triSurfaceTools.H"
using namespace Foam;
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
void writeOBJ(Ostream& os, const pointField& pts)
{
forAll(pts, i)
{
const point& pt = pts[i];
os << "v " << pt.x() << ' ' << pt.y() << ' ' << pt.z() << endl;
}
}
void dumpPoints(const triSurface& surf, const labelList& borderPoint)
{
fileName fName("borderPoints.obj");
Info<< "Dumping borderPoints as Lightwave .obj file to " << fName
<< "\nThis can be visualized with e.g. javaview (www.javaview.de)\n\n";
OFstream os(fName);
forAll(borderPoint, pointI)
{
if (borderPoint[pointI] != -1)
{
const point& pt = surf.localPoints()[pointI];
os << "v " << pt.x() << ' ' << pt.y() << ' ' << pt.z() << endl;
}
}
}
void dumpEdges(const triSurface& surf, const boolList& borderEdge)
{
fileName fName("borderEdges.obj");
Info<< "Dumping borderEdges as Lightwave .obj file to " << fName
<< "\nThis can be visualized with e.g. javaview (www.javaview.de)\n\n";
OFstream os(fName);
writeOBJ(os, surf.localPoints());
forAll(borderEdge, edgeI)
{
if (borderEdge[edgeI])
{
const edge& e = surf.edges()[edgeI];
os << "l " << e.start()+1 << ' ' << e.end()+1 << endl;
}
}
}
void dumpFaces
(
const fileName& fName,
const triSurface& surf,
const Map<label>& connectedFaces
)
{
Info<< "Dumping connectedFaces as Lightwave .obj file to " << fName
<< "\nThis can be visualized with e.g. javaview (www.javaview.de)\n\n";
OFstream os(fName);
for
(
Map<label>::const_iterator iter = connectedFaces.begin();
iter != connectedFaces.end();
++iter
)
{
const labelledTri& f = surf.localFaces()[iter.key()];
point ctr(f.centre(surf.localPoints()));
os << "v " << ctr.x() << ' ' << ctr.y() << ' ' << ctr.z() << endl;
}
}
void testSortedEdgeFaces(const triSurface& surf)
{
const labelListList& edgeFaces = surf.edgeFaces();
const labelListList& sortedEdgeFaces = surf.sortedEdgeFaces();
forAll(edgeFaces, edgeI)
{
const labelList& myFaces = edgeFaces[edgeI];
const labelList& sortMyFaces = sortedEdgeFaces[edgeI];
forAll(myFaces, i)
{
if (findIndex(sortMyFaces, myFaces[i]) == -1)
{
FatalErrorIn("testSortedEdgeFaces(..)") << abort(FatalError);
}
}
forAll(sortMyFaces, i)
{
if (findIndex(myFaces, sortMyFaces[i]) == -1)
{
FatalErrorIn("testSortedEdgeFaces(..)") << abort(FatalError);
}
}
}
}
// Mark off all border edges. Return number of border edges.
label markBorderEdges
(
const bool debug,
const triSurface& surf,
boolList& borderEdge
)
{
label nBorderEdges = 0;
const labelListList& edgeFaces = surf.edgeFaces();
forAll(edgeFaces, edgeI)
{
if (edgeFaces[edgeI].size() == 4)
{
borderEdge[edgeI] = true;
nBorderEdges++;
}
}
if (debug)
{
dumpEdges(surf, borderEdge);
}
return nBorderEdges;
}
// Mark off all border points. Return number of border points. Border points
// marked by setting value to newly introduced point.
label markBorderPoints
(
const bool debug,
const triSurface& surf,
const boolList& borderEdge,
labelList& borderPoint
)
{
label nPoints = surf.nPoints();
const labelListList& pointEdges = surf.pointEdges();
forAll(pointEdges, pointI)
{
const labelList& pEdges = pointEdges[pointI];
label nBorderEdges = 0;
forAll(pEdges, i)
{
if (borderEdge[pEdges[i]])
{
nBorderEdges++;
}
}
if (nBorderEdges == 2 && borderPoint[pointI] == -1)
{
borderPoint[pointI] = nPoints++;
}
}
label nBorderPoints = nPoints - surf.nPoints();
if (debug)
{
dumpPoints(surf, borderPoint);
}
return nBorderPoints;
}
// Get minumum length of edges connected to pointI
// Serves to get some local length scale.
scalar minEdgeLen(const triSurface& surf, const label pointI)
{
const pointField& points = surf.localPoints();
const labelList& pEdges = surf.pointEdges()[pointI];
scalar minLen = GREAT;
forAll(pEdges, i)
{
label edgeI = pEdges[i];
scalar len = surf.edges()[edgeI].mag(points);
if (len < minLen)
{
minLen = len;
}
}
return minLen;
}
// Find edge among edgeLabels with endpoints v0,v1
label findEdge
(
const triSurface& surf,
const labelList& edgeLabels,
const label v0,
const label v1
)
{
forAll(edgeLabels, i)
{
label edgeI = edgeLabels[i];
const edge& e = surf.edges()[edgeI];
if
(
(
e.start() == v0
&& e.end() == v1
)
|| (
e.start() == v1
&& e.end() == v0
)
)
{
return edgeI;
}
}
FatalErrorIn("findEdge(..)") << "Cannot find edge with labels " << v0
<< ' ' << v1 << " in candidates " << edgeLabels
<< " with vertices:" << UIndirectList<edge>(surf.edges(), edgeLabels)()
<< abort(FatalError);
return -1;
}
// Get the other edge connected to pointI on faceI.
label otherEdge
(
const triSurface& surf,
const label faceI,
const label otherEdgeI,
const label pointI
)
{
const labelList& fEdges = surf.faceEdges()[faceI];
forAll(fEdges, i)
{
label edgeI = fEdges[i];
const edge& e = surf.edges()[edgeI];
if
(
edgeI != otherEdgeI
&& (
e.start() == pointI
|| e.end() == pointI
)
)
{
return edgeI;
}
}
FatalErrorIn("otherEdge(..)") << "Cannot find other edge on face " << faceI
<< " verts:" << surf.localPoints()[faceI]
<< " connected to point " << pointI
<< " faceEdges:" << UIndirectList<edge>(surf.edges(), fEdges)()
<< abort(FatalError);
return -1;
}
// Starting from startPoint on startEdge on startFace walk along border
// and insert faces along the way. Walk keeps always one point or one edge
// on the border line.
void walkSplitLine
(
const triSurface& surf,
const boolList& borderEdge,
const labelList& borderPoint,
const label startFaceI,
const label startEdgeI, // is border edge
const label startPointI, // is border point
Map<label>& faceToEdge,
Map<label>& faceToPoint
)
{
label faceI = startFaceI;
label edgeI = startEdgeI;
label pointI = startPointI;
do
{
//
// Stick to pointI and walk face-edge-face until back on border edge.
//
do
{
// Cross face to next edge.
edgeI = otherEdge(surf, faceI, edgeI, pointI);
if (borderEdge[edgeI])
{
if (!faceToEdge.insert(faceI, edgeI))
{
// Was already visited.
return;
}
else
{
// First visit to this borderEdge. We're back on borderline.
break;
}
}
else if (!faceToPoint.insert(faceI, pointI))
{
// Was already visited.
return;
}
// Cross edge to other face
const labelList& eFaces = surf.edgeFaces()[edgeI];
if (eFaces.size() != 2)
{
FatalErrorIn("walkSplitPoint(..)")
<< "Can only handle edges with 2 or 4 edges for now."
<< abort(FatalError);
}
if (eFaces[0] == faceI)
{
faceI = eFaces[1];
}
else if (eFaces[1] == faceI)
{
faceI = eFaces[0];
}
else
{
FatalErrorIn("walkSplitPoint(..)") << abort(FatalError);
}
}
while (true);
//
// Back on border edge. Cross to other point on edge.
//
pointI = surf.edges()[edgeI].otherVertex(pointI);
if (borderPoint[pointI] == -1)
{
return;
}
}
while (true);
}
// Find second face which is from same surface i.e. has points on the
// shared edge in reverse order.
label sharedFace
(
const triSurface& surf,
const label firstFaceI,
const label sharedEdgeI
)
{
// Find ordering of face points in edge.
const edge& e = surf.edges()[sharedEdgeI];
const labelledTri& f = surf.localFaces()[firstFaceI];
label startIndex = findIndex(f, e.start());
// points in face in same order as edge
bool edgeOrder = (f[f.fcIndex(startIndex)] == e.end());
// Get faces using edge in sorted order. (sorted such that walking
// around them in anti-clockwise order corresponds to edge vector
// acc. to right-hand rule)
const labelList& eFaces = surf.sortedEdgeFaces()[sharedEdgeI];
// Get position of face in sorted edge faces
label faceIndex = findIndex(eFaces, firstFaceI);
if (edgeOrder)
{
// Get face before firstFaceI
return eFaces[eFaces.rcIndex(faceIndex)];
}
else
{
// Get face after firstFaceI
return eFaces[eFaces.fcIndex(faceIndex)];
}
}
// Calculate (inward pointing) normals on edges shared by faces in faceToEdge and
// averages them to pointNormals.
void calcPointVecs
(
const triSurface& surf,
const Map<label>& faceToEdge,
const Map<label>& faceToPoint,
vectorField& borderPointVec
)
{
const labelListList& sortedEdgeFaces = surf.sortedEdgeFaces();
const edgeList& edges = surf.edges();
const pointField& points = surf.localPoints();
boolList edgeDone(surf.nEdges(), false);
for
(
Map<label>::const_iterator iter = faceToEdge.begin();
iter != faceToEdge.end();
++iter
)
{
label edgeI = iter();
if (!edgeDone[edgeI])
{
edgeDone[edgeI] = true;
// Get the two connected faces in sorted order
// Note: should have stored this when walking ...
label face0I = -1;
label face1I = -1;
const labelList& eFaces = sortedEdgeFaces[edgeI];
forAll(eFaces, i)
{
label faceI = eFaces[i];
if (faceToEdge.found(faceI))
{
if (face0I == -1)
{
face0I = faceI;
}
else if (face1I == -1)
{
face1I = faceI;
break;
}
}
}
if (face0I == -1 && face1I == -1)
{
Info<< "Writing surface to errorSurf.ftr" << endl;
surf.write("errorSurf.ftr");
FatalErrorIn("calcPointVecs(..)")
<< "Cannot find two faces using border edge " << edgeI
<< " verts:" << edges[edgeI]
<< " eFaces:" << eFaces << endl
<< "face0I:" << face0I
<< " face1I:" << face1I << nl
<< "faceToEdge:" << faceToEdge << nl
<< "faceToPoint:" << faceToPoint
<< "Written surface to errorSurf.ftr"
<< abort(FatalError);
}
// Now we have edge and the two faces in counter-clockwise order
// as seen from edge vector. Calculate normal.
const edge& e = edges[edgeI];
vector eVec = e.vec(points);
// Determine vector as average of the vectors in the two faces.
// If there is only one face available use only one vector.
vector midVec(vector::zero);
if (face0I != -1)
{
label v0 = triSurfaceTools::oppositeVertex(surf, face0I, edgeI);
vector e0 = (points[v0] - points[e.start()]) ^ eVec;
e0 /= mag(e0);
midVec = e0;
}
if (face1I != -1)
{
label v1 = triSurfaceTools::oppositeVertex(surf, face1I, edgeI);
vector e1 = (points[e.start()] - points[v1]) ^ eVec;
e1 /= mag(e1);
midVec += e1;
}
scalar magMidVec = mag(midVec);
if (magMidVec > SMALL)
{
midVec /= magMidVec;
// Average to pointVec
borderPointVec[e.start()] += midVec;
borderPointVec[e.end()] += midVec;
}
}
}
}
// Renumbers vertices (of triangles in faceToEdge) of which the pointMap is
// not -1.
void renumberFaces
(
const triSurface& surf,
const labelList& pointMap,
const Map<label>& faceToEdge,
List<labelledTri>& newTris
)
{
for
(
Map<label>::const_iterator iter = faceToEdge.begin();
iter != faceToEdge.end();
++iter
)
{
label faceI = iter.key();
const labelledTri& f = surf.localFaces()[faceI];
forAll(f, fp)
{
if (pointMap[f[fp]] != -1)
{
newTris[faceI][fp] = pointMap[f[fp]];
}
}
}
}
// Split all borderEdges that don't have borderPoint. Return true if split
// anything.
bool splitBorderEdges
(
triSurface& surf,
const boolList& borderEdge,
const labelList& borderPoint
)
{
labelList edgesToBeSplit(surf.nEdges());
label nSplit = 0;
forAll(borderEdge, edgeI)
{
if (borderEdge[edgeI])
{
const edge& e = surf.edges()[edgeI];
if (borderPoint[e.start()] == -1 && borderPoint[e.end()] == -1)
{
// None of the points of the edge is borderPoint. Split edge
// to introduce border point.
edgesToBeSplit[nSplit++] = edgeI;
}
}
}
edgesToBeSplit.setSize(nSplit);
if (nSplit > 0)
{
Info<< "Splitting surface along " << nSplit << " borderEdges that don't"
<< " neighbour other borderEdges" << nl << endl;
surf = triSurfaceTools::greenRefine(surf, edgesToBeSplit);
return true;
}
else
{
Info<< "No edges to be split" <<nl << endl;
return false;
}
}
// Main program:
int main(int argc, char *argv[])
{
argList::noParallel();
argList::validArgs.clear();
argList::validArgs.append("surface file");
argList::validArgs.append("output surface file");
argList::validOptions.insert("debug", "");
argList args(argc, argv);
fileName inSurfName(args.additionalArgs()[0]);
fileName outSurfName(args.additionalArgs()[1]);
bool debug = args.optionFound("debug");
Info<< "Reading surface from " << inSurfName << endl;
triSurface surf(inSurfName);
// Make sure sortedEdgeFaces is calculated correctly
testSortedEdgeFaces(surf);
// Get all quad connected edges. These are seen as borders when walking.
boolList borderEdge(surf.nEdges(), false);
markBorderEdges(debug, surf, borderEdge);
// Points on two sides connected to borderEdges are called borderPoints and
// will be duplicated. borderPoint contains label of newly introduced vertex.
labelList borderPoint(surf.nPoints(), -1);
markBorderPoints(debug, surf, borderEdge, borderPoint);
// Split edges where there would be no borderPoint to duplicate.
splitBorderEdges(surf, borderEdge, borderPoint);
Info<< "Writing split surface to " << outSurfName << nl << endl;
surf.write(outSurfName);
Info<< "Finished writing surface to " << outSurfName << nl << endl;
// Last iteration values.
label nOldBorderEdges = -1;
label nOldBorderPoints = -1;
label iteration = 0;
do
{
// Redo borderEdge/borderPoint calculation.
boolList borderEdge(surf.nEdges(), false);
label nBorderEdges = markBorderEdges(debug, surf, borderEdge);
if (nBorderEdges == 0)
{
Info<< "Found no border edges. Exiting." << nl << nl;
break;
}
// Label of newly introduced duplicate.
labelList borderPoint(surf.nPoints(), -1);
label nBorderPoints =
markBorderPoints
(
debug,
surf,
borderEdge,
borderPoint
);
if (nBorderPoints == 0)
{
Info<< "Found no border points. Exiting." << nl << nl;
break;
}
Info<< "Found:\n"
<< " border edges :" << nBorderEdges << nl
<< " border points:" << nBorderPoints << nl
<< endl;
if
(
nBorderPoints == nOldBorderPoints
&& nBorderEdges == nOldBorderEdges
)
{
Info<< "Stopping since number of border edges and point is same"
<< " as in previous iteration" << nl << endl;
break;
}
//
// Define splitLine as a series of connected borderEdges. Find start
// of one (as edge and point on edge)
//
label startEdgeI = -1;
label startPointI = -1;
forAll(borderEdge, edgeI)
{
if (borderEdge[edgeI])
{
const edge& e = surf.edges()[edgeI];
if ((borderPoint[e[0]] != -1) && (borderPoint[e[1]] == -1))
{
startEdgeI = edgeI;
startPointI = e[0];
break;
}
else if ((borderPoint[e[0]] == -1) && (borderPoint[e[1]] != -1))
{
startEdgeI = edgeI;
startPointI = e[1];
break;
}
}
}
if (startEdgeI == -1)
{
Info<< "Cannot find starting point of splitLine\n" << endl;
break;
}
// Pick any face using edge to start from.
const labelList& eFaces = surf.edgeFaces()[startEdgeI];
label firstFaceI = eFaces[0];
// Find second face which is from same surface i.e. has outwards
// pointing normal as well (actually bit more complex than this)
label secondFaceI = sharedFace(surf, firstFaceI, startEdgeI);
Info<< "Starting local walk from:" << endl
<< " edge :" << startEdgeI << endl
<< " point:" << startPointI << endl
<< " face0:" << firstFaceI << endl
<< " face1:" << secondFaceI << endl
<< endl;
// From face on border edge to edge.
Map<label> faceToEdge(2*nBorderEdges);
// From face connected to border point (but not border edge) to point.
Map<label> faceToPoint(2*nBorderPoints);
faceToEdge.insert(firstFaceI, startEdgeI);
walkSplitLine
(
surf,
borderEdge,
borderPoint,
firstFaceI,
startEdgeI,
startPointI,
faceToEdge,
faceToPoint
);
faceToEdge.insert(secondFaceI, startEdgeI);
walkSplitLine
(
surf,
borderEdge,
borderPoint,
secondFaceI,
startEdgeI,
startPointI,
faceToEdge,
faceToPoint
);
Info<< "Finished local walk and visited" << nl
<< " border edges :" << faceToEdge.size() << nl
<< " border points(but not edges):" << faceToPoint.size() << nl
<< endl;
if (debug)
{
dumpFaces("faceToEdge.obj", surf, faceToEdge);
dumpFaces("faceToPoint.obj", surf, faceToPoint);
}
//
// Create coordinates for borderPoints by duplicating the existing
// point and then slightly shifting it inwards. To determine the
// inwards direction get the average normal of both connectedFaces on
// the edge and then interpolate this to the (border)point.
//
vectorField borderPointVec(surf.nPoints(), vector(GREAT, GREAT, GREAT));
calcPointVecs(surf, faceToEdge, faceToPoint, borderPointVec);
// New position. Start off from copy of old points.
pointField newPoints(surf.localPoints());
newPoints.setSize(newPoints.size() + nBorderPoints);
forAll(borderPoint, pointI)
{
label newPointI = borderPoint[pointI];
if (newPointI != -1)
{
scalar minLen = minEdgeLen(surf, pointI);
vector n = borderPointVec[pointI];
n /= mag(n);
newPoints[newPointI] = newPoints[pointI] + 0.1 * minLen * n;
}
}
//
// Renumber all faces in connectedFaces
//
// Start off from copy of faces.
List<labelledTri> newTris(surf.size());
forAll(surf, faceI)
{
newTris[faceI] = surf.localFaces()[faceI];
newTris[faceI].region() = surf[faceI].region();
}
// Renumber all faces in faceToEdge
renumberFaces(surf, borderPoint, faceToEdge, newTris);
// Renumber all faces in faceToPoint
renumberFaces(surf, borderPoint, faceToPoint, newTris);
// Check if faces use unmoved points.
forAll(newTris, faceI)
{
const labelledTri& f = newTris[faceI];
forAll(f, fp)
{
const point& pt = newPoints[f[fp]];
if (mag(pt) >= GREAT/2)
{
Info<< "newTri:" << faceI << " verts:" << f
<< " vert:" << f[fp] << " point:" << pt << endl;
}
}
}
surf = triSurface(newTris, surf.patches(), newPoints);
if (debug || (iteration != 0 && (iteration % 20) == 0))
{
Info<< "Writing surface to " << outSurfName << nl << endl;
surf.write(outSurfName);
Info<< "Finished writing surface to " << outSurfName << nl << endl;
}
// Save prev iteration values.
nOldBorderEdges = nBorderEdges;
nOldBorderPoints = nBorderPoints;
iteration++;
}
while (true);
Info<< "Writing final surface to " << outSurfName << nl << endl;
surf.write(outSurfName);
Info << "End\n" << endl;
return 0;
}
// ************************************************************************* //