netgen/libsrc/meshing/improve2.cpp
2019-08-18 13:10:58 +02:00

847 lines
20 KiB
C++

#include <mystdlib.h>
#include "meshing.hpp"
#include <opti.hpp>
namespace netgen
{
class Neighbour
{
int nr[3];
int orient[3];
public:
Neighbour () { ; }
void SetNr (int side, int anr) { nr[side] = anr; }
int GetNr (int side) { return nr[side]; }
void SetOrientation (int side, int aorient) { orient[side] = aorient; }
int GetOrientation (int side) { return orient[side]; }
};
class trionedge
{
public:
SurfaceElementIndex tnr;
int sidenr;
trionedge () { tnr = 0; sidenr = 0; }
trionedge (SurfaceElementIndex atnr, int asidenr)
{ tnr = atnr; sidenr = asidenr; }
};
void MeshOptimize2d :: EdgeSwapping (Mesh & mesh, int usemetric)
{
if (!faceindex)
{
if (usemetric)
PrintMessage (3, "Edgeswapping, metric");
else
PrintMessage (3, "Edgeswapping, topological");
for (faceindex = 1; faceindex <= mesh.GetNFD(); faceindex++)
{
EdgeSwapping (mesh, usemetric);
if (multithread.terminate)
throw NgException ("Meshing stopped");
}
faceindex = 0;
mesh.CalcSurfacesOfNode();
return;
}
static int timer = NgProfiler::CreateTimer ("EdgeSwapping 2D");
NgProfiler::RegionTimer reg1 (timer);
static int timerstart = NgProfiler::CreateTimer ("EdgeSwapping 2D start");
NgProfiler::StartTimer (timerstart);
Array<SurfaceElementIndex> seia;
mesh.GetSurfaceElementsOfFace (faceindex, seia);
/*
for (int i = 0; i < seia.Size(); i++)
if (mesh[seia[i]].GetNP() != 3)
{
GenericImprove (mesh);
return;
}
*/
for (SurfaceElementIndex sei : seia)
if (mesh[sei].GetNP() != 3)
{
GenericImprove (mesh);
return;
}
int surfnr = mesh.GetFaceDescriptor (faceindex).SurfNr();
Array<Neighbour> neighbors(mesh.GetNSE());
INDEX_2_HASHTABLE<trionedge> other(2*seia.Size() + 2);
Array<bool> swapped(mesh.GetNSE());
NgArray<int,PointIndex::BASE> pdef(mesh.GetNP());
NgArray<double,PointIndex::BASE> pangle(mesh.GetNP());
// int e;
// double d;
// Vec3d nv1, nv2;
// double loch(-1);
static const double minangle[] = { 0, 1.481, 2.565, 3.627, 4.683, 5.736, 7, 9 };
for (int i = 0; i < seia.Size(); i++)
{
const Element2d & sel = mesh[seia[i]];
for (int j = 0; j < 3; j++)
pangle[sel[j]] = 0.0;
}
// pangle = 0;
for (int i = 0; i < seia.Size(); i++)
{
const Element2d & sel = mesh[seia[i]];
for (int j = 0; j < 3; j++)
{
POINTTYPE typ = mesh[sel[j]].Type();
if (typ == FIXEDPOINT || typ == EDGEPOINT)
{
pangle[sel[j]] +=
Angle (mesh[sel[(j+1)%3]] - mesh[sel[j]],
mesh[sel[(j+2)%3]] - mesh[sel[j]]);
}
}
}
// for (PointIndex pi = PointIndex::BASE;
// pi < mesh.GetNP()+PointIndex::BASE; pi++)
// pdef = 0;
for (int i = 0; i < seia.Size(); i++)
{
const Element2d & sel = mesh[seia[i]];
for (int j = 0; j < 3; j++)
{
PointIndex pi = sel[j];
if (mesh[pi].Type() == INNERPOINT || mesh[pi].Type() == SURFACEPOINT)
pdef[pi] = -6;
else
for (int j = 0; j < 8; j++)
if (pangle[pi] >= minangle[j])
pdef[pi] = -1-j;
}
}
/*
for (int i = 0; i < seia.Size(); i++)
{
const Element2d & sel = mesh[seia[i]];
for (int j = 0; j < 3; j++)
pdef[sel[j]]++;
}
*/
for (SurfaceElementIndex sei : seia)
for (PointIndex pi : mesh[sei].PNums<3>())
pdef[pi]++;
// for (int i = 0; i < seia.Size(); i++)
for (SurfaceElementIndex sei : seia)
for (int j = 0; j < 3; j++)
{
neighbors[sei].SetNr (j, -1);
neighbors[sei].SetOrientation (j, 0);
}
/*
NgArray<Vec3d> normals(mesh.GetNP());
for (i = 1; i <= mesh.GetNSE(); i++)
{
Element2d & hel = mesh.SurfaceElement(i);
if (hel.GetIndex() == faceindex)
for (k = 1; k <= 3; k++)
{
int pi = hel.PNum(k);
SelectSurfaceOfPoint (mesh.Point(pi), hel.GeomInfoPi(k));
int surfi = mesh.GetFaceDescriptor(faceindex).SurfNr();
GetNormalVector (surfi, mesh.Point(pi), normals.Elem(pi));
normals.Elem(pi) /= normals.Elem(pi).Length();
}
}
*/
/*
for (int i = 0; i < seia.Size(); i++)
{
const Element2d & sel = mesh[seia[i]];
*/
for (SurfaceElementIndex sei : seia)
{
const Element2d & sel = mesh[sei];
for (int j = 0; j < 3; j++)
{
PointIndex pi1 = sel.PNumMod(j+2);
PointIndex pi2 = sel.PNumMod(j+3);
// double loch = mesh.GetH(mesh[pi1]);
// INDEX_2 edge(pi1, pi2);
// edge.Sort();
if (mesh.IsSegment (pi1, pi2))
continue;
/*
if (segments.Used (edge))
continue;
*/
INDEX_2 ii2 (pi1, pi2);
if (other.Used (ii2))
{
// INDEX_2 i2s(ii2);
// i2s.Sort();
/*
int i2 = other.Get(ii2).tnr;
int j2 = other.Get(ii2).sidenr;
*/
auto othertrig = other.Get(ii2);
SurfaceElementIndex i2 = othertrig.tnr;
int j2 = othertrig.sidenr;
neighbors[sei].SetNr (j, i2);
neighbors[sei].SetOrientation (j, j2);
neighbors[i2].SetNr (j2, sei);
neighbors[i2].SetOrientation (j2, j);
}
else
{
other.Set (INDEX_2 (pi2, pi1), trionedge (sei, j));
}
}
}
for (SurfaceElementIndex sei : seia)
swapped[sei] = false;
NgProfiler::StopTimer (timerstart);
int t = 4;
bool done = false;
while (!done && t >= 2)
{
for (int i = 0; i < seia.Size(); i++)
{
SurfaceElementIndex t1 = seia[i];
if (mesh[t1].IsDeleted())
continue;
if (mesh[t1].GetIndex() != faceindex)
continue;
if (multithread.terminate)
throw NgException ("Meshing stopped");
for (int o1 = 0; o1 < 3; o1++)
{
bool should;
SurfaceElementIndex t2 = neighbors[t1].GetNr (o1);
int o2 = neighbors[t1].GetOrientation (o1);
if (t2 == -1) continue;
if (swapped[t1] || swapped[t2]) continue;
PointIndex pi1 = mesh[t1].PNumMod(o1+1+1);
PointIndex pi2 = mesh[t1].PNumMod(o1+1+2);
PointIndex pi3 = mesh[t1].PNumMod(o1+1);
PointIndex pi4 = mesh[t2].PNumMod(o2+1);
PointGeomInfo gi1 = mesh[t1].GeomInfoPiMod(o1+1+1);
PointGeomInfo gi2 = mesh[t1].GeomInfoPiMod(o1+1+2);
PointGeomInfo gi3 = mesh[t1].GeomInfoPiMod(o1+1);
PointGeomInfo gi4 = mesh[t2].GeomInfoPiMod(o2+1);
bool allowswap = true;
Vec<3> auxvec1 = mesh[pi3]-mesh[pi4];
Vec<3> auxvec2 = mesh[pi1]-mesh[pi4];
allowswap = allowswap && fabs(1.-(auxvec1*auxvec2)/(auxvec1.Length()*auxvec2.Length())) > 1e-4;
if(!allowswap)
continue;
// normal of new
Vec<3> nv1 = Cross (auxvec1, auxvec2);
auxvec1 = mesh.Point(pi4)-mesh.Point(pi3);
auxvec2 = mesh.Point(pi2)-mesh.Point(pi3);
allowswap = allowswap && fabs(1.-(auxvec1*auxvec2)/(auxvec1.Length()*auxvec2.Length())) > 1e-4;
if(!allowswap)
continue;
Vec<3> nv2 = Cross (auxvec1, auxvec2);
// normals of original
Vec<3> nv3 = Cross (mesh[pi1]-mesh[pi4], mesh[pi2]-mesh[pi4]);
Vec<3> nv4 = Cross (mesh[pi2]-mesh[pi3], mesh[pi1]-mesh[pi3]);
nv3 *= -1;
nv4 *= -1;
nv3.Normalize();
nv4.Normalize();
nv1.Normalize();
nv2.Normalize();
Vec<3> nvp3, nvp4;
SelectSurfaceOfPoint (mesh.Point(pi3), gi3);
GetNormalVector (surfnr, mesh.Point(pi3), gi3, nvp3);
nvp3.Normalize();
SelectSurfaceOfPoint (mesh.Point(pi4), gi4);
GetNormalVector (surfnr, mesh.Point(pi4), gi4, nvp4);
nvp4.Normalize();
double critval = cos (M_PI / 6); // 30 degree
allowswap = allowswap &&
(nv1 * nvp3 > critval) &&
(nv1 * nvp4 > critval) &&
(nv2 * nvp3 > critval) &&
(nv2 * nvp4 > critval) &&
(nvp3 * nv3 > critval) &&
(nvp4 * nv4 > critval);
double horder = Dist (mesh[pi1], mesh[pi2]);
if ( // nv1 * nv2 >= 0 &&
nv1.Length() > 1e-3 * horder * horder &&
nv2.Length() > 1e-3 * horder * horder &&
allowswap )
{
if (!usemetric)
{
int e = pdef[pi1] + pdef[pi2] - pdef[pi3] - pdef[pi4];
double d =
Dist2 (mesh[pi1], mesh[pi2]) -
Dist2 (mesh[pi3], mesh[pi4]);
should = e >= t && (e > 2 || d > 0);
}
else
{
double loch = mesh.GetH(mesh[pi1]);
should =
CalcTriangleBadness (mesh[pi4], mesh[pi3], mesh[pi1], metricweight, loch) +
CalcTriangleBadness (mesh[pi3], mesh[pi4], mesh[pi2], metricweight, loch) <
CalcTriangleBadness (mesh[pi1], mesh[pi2], mesh[pi3], metricweight, loch) +
CalcTriangleBadness (mesh[pi2], mesh[pi1], mesh[pi4], metricweight, loch);
}
if (allowswap)
{
Element2d sw1 (pi4, pi3, pi1);
Element2d sw2 (pi3, pi4, pi2);
int legal1 =
mesh.LegalTrig (mesh[t1]) +
mesh.LegalTrig (mesh[t2]);
int legal2 =
mesh.LegalTrig (sw1) + mesh.LegalTrig (sw2);
if (legal1 < legal2) should = true;
if (legal2 < legal1) should = false;
}
if (should)
{
// do swapping !
done = true;
/*
mesh[t1] = { pi1, pi4, pi3 };
mesh[t2] = { pi2, pi3, pi4 };
mesh[t1].GeomInfoPi(1) = gi1;
mesh[t1].GeomInfoPi(2) = gi4;
mesh[t1].GeomInfoPi(3) = gi3;
mesh[t2].GeomInfoPi(1) = gi2;
mesh[t2].GeomInfoPi(2) = gi3;
mesh[t2].GeomInfoPi(3) = gi4;
*/
mesh[t1] = { { pi1, gi1 }, { pi4, gi4 }, { pi3, gi3 } };
mesh[t2] = { { pi2, gi2 }, { pi3, gi3 }, { pi4, gi4 } };
pdef[pi1]--;
pdef[pi2]--;
pdef[pi3]++;
pdef[pi4]++;
swapped[t1] = true;
swapped[t2] = true;
}
}
}
}
t--;
}
mesh.SetNextTimeStamp();
}
void MeshOptimize2d :: CombineImprove (Mesh & mesh)
{
if (!faceindex)
{
PrintMessage (3, "Combine improve");
for (faceindex = 1; faceindex <= mesh.GetNFD(); faceindex++)
{
CombineImprove (mesh);
if (multithread.terminate)
throw NgException ("Meshing stopped");
}
faceindex = 0;
return;
}
static int timer = NgProfiler::CreateTimer ("Combineimprove 2D");
NgProfiler::RegionTimer reg (timer);
static int timerstart = NgProfiler::CreateTimer ("Combineimprove 2D start");
NgProfiler::StartTimer (timerstart);
static int timerstart1 = NgProfiler::CreateTimer ("Combineimprove 2D start1");
NgProfiler::StartTimer (timerstart1);
Array<SurfaceElementIndex> seia;
mesh.GetSurfaceElementsOfFace (faceindex, seia);
for (SurfaceElementIndex sei : seia)
if (mesh[sei].GetNP() != 3)
return;
int surfnr = 0;
if (faceindex)
surfnr = mesh.GetFaceDescriptor (faceindex).SurfNr();
Vec<3> nv;
int np = mesh.GetNP();
TABLE<SurfaceElementIndex,PointIndex::BASE> elementsonnode(np);
Array<SurfaceElementIndex> hasonepi, hasbothpi;
for (SurfaceElementIndex sei : seia)
for (PointIndex pi : mesh[sei].PNums<3>())
elementsonnode.Add (pi, sei);
Array<bool,PointIndex> fixed(np);
fixed = false;
NgProfiler::StopTimer (timerstart1);
/*
for (SegmentIndex si = 0; si < mesh.GetNSeg(); si++)
{
INDEX_2 i2(mesh[si][0], mesh[si][1]);
fixed[i2.I1()] = true;
fixed[i2.I2()] = true;
}
*/
for (SurfaceElementIndex sei : seia)
{
Element2d & sel = mesh[sei];
for (int j = 0; j < sel.GetNP(); j++)
{
PointIndex pi1 = sel.PNumMod(j+2);
PointIndex pi2 = sel.PNumMod(j+3);
if (mesh.IsSegment (pi1, pi2))
{
fixed[pi1] = true;
fixed[pi2] = true;
}
}
}
/*
for(int i = 0; i < mesh.LockedPoints().Size(); i++)
fixed[mesh.LockedPoints()[i]] = true;
*/
for (PointIndex pi : mesh.LockedPoints())
fixed[pi] = true;
Array<Vec<3>,PointIndex> normals(np);
// for (PointIndex pi = mesh.Points().Begin(); pi < mesh.Points().End(); pi++)
for (PointIndex pi : mesh.Points().Range())
{
if (elementsonnode[pi].Size())
{
Element2d & hel = mesh[elementsonnode[pi][0]];
for (int k = 0; k < 3; k++)
if (hel[k] == pi)
{
SelectSurfaceOfPoint (mesh[pi], hel.GeomInfoPi(k+1));
GetNormalVector (surfnr, mesh[pi], hel.GeomInfoPi(k+1), normals[pi]);
break;
}
}
}
NgProfiler::StopTimer (timerstart);
for (int i = 0; i < seia.Size(); i++)
{
SurfaceElementIndex sei = seia[i];
Element2d & elem = mesh[sei];
if (elem.IsDeleted()) continue;
for (int j = 0; j < 3; j++)
{
PointIndex pi1 = elem[j];
PointIndex pi2 = elem[(j+1) % 3];
/*
if (pi1 < PointIndex::BASE ||
pi2 < PointIndex::BASE)
continue;
*/
if (!pi1.IsValid() || !pi2.IsValid())
continue;
/*
INDEX_2 i2(pi1, pi2);
i2.Sort();
if (segmentht.Used(i2))
continue;
*/
bool debugflag = 0;
if (debugflag)
{
(*testout) << "Combineimprove, face = " << faceindex
<< "pi1 = " << pi1 << " pi2 = " << pi2 << endl;
}
/*
// save version:
if (fixed.Get(pi1) || fixed.Get(pi2))
continue;
if (pi2 < pi1) swap (pi1, pi2);
*/
// more general
if (fixed[pi2])
Swap (pi1, pi2);
if (fixed[pi2])
continue;
double loch = mesh.GetH (mesh[pi1]);
// INDEX_2 si2 (pi1, pi2);
// si2.Sort();
/*
if (edgetested.Used (si2))
continue;
edgetested.Set (si2, 1);
*/
hasonepi.SetSize(0);
hasbothpi.SetSize(0);
// for (int k = 0; k < elementsonnode[pi1].Size(); k++)
for (SurfaceElementIndex sei2 : elementsonnode[pi1])
{
const Element2d & el2 = mesh[sei2];
if (el2.IsDeleted()) continue;
if (el2[0] == pi2 || el2[1] == pi2 || el2[2] == pi2)
{
hasbothpi.Append (sei2);
nv = Cross (Vec3d (mesh[el2[0]], mesh[el2[1]]),
Vec3d (mesh[el2[0]], mesh[el2[2]]));
}
else
{
hasonepi.Append (sei2);
}
}
Element2d & hel = mesh[hasbothpi[0]];
for (int k = 0; k < 3; k++)
if (hel[k] == pi1)
{
SelectSurfaceOfPoint (mesh[pi1],
hel.GeomInfoPi(k+1));
GetNormalVector (surfnr, mesh[pi1], hel.GeomInfoPi(k+1), nv);
break;
}
// nv = normals.Get(pi1);
for (SurfaceElementIndex sei2 : elementsonnode[pi2])
{
const Element2d & el2 = mesh[sei2];
if (el2.IsDeleted()) continue;
if (!el2.PNums<3>().Contains (pi1))
hasonepi.Append (sei2);
}
double bad1 = 0;
int illegal1 = 0, illegal2 = 0;
/*
for (SurfaceElementIndex sei : hasonepi)
{
const Element2d & el = mesh[sei];
bad1 += CalcTriangleBadness (mesh[el[0]], mesh[el[1]], mesh[el[2]],
nv, -1, loch);
illegal1 += 1-mesh.LegalTrig(el);
}
*/
for (const Element2d & el : mesh.SurfaceElements()[hasonepi])
{
bad1 += CalcTriangleBadness (mesh[el[0]], mesh[el[1]], mesh[el[2]],
nv, -1, loch);
illegal1 += 1-mesh.LegalTrig(el);
}
for (int k = 0; k < hasbothpi.Size(); k++)
{
const Element2d & el = mesh[hasbothpi[k]];
bad1 += CalcTriangleBadness (mesh[el[0]], mesh[el[1]], mesh[el[2]],
nv, -1, loch);
illegal1 += 1-mesh.LegalTrig(el);
}
bad1 /= (hasonepi.Size()+hasbothpi.Size());
MeshPoint p1 = mesh[pi1];
MeshPoint p2 = mesh[pi2];
MeshPoint pnew = p1;
mesh[pi1] = pnew;
mesh[pi2] = pnew;
double bad2 = 0;
for (int k = 0; k < hasonepi.Size(); k++)
{
Element2d & el = mesh[hasonepi[k]];
double err =
CalcTriangleBadness (mesh[el[0]], mesh[el[1]], mesh[el[2]],
nv, -1, loch);
bad2 += err;
Vec<3> hnv = Cross (Vec3d (mesh[el[0]],
mesh[el[1]]),
Vec3d (mesh[el[0]],
mesh[el[2]]));
if (hnv * nv < 0)
bad2 += 1e10;
for (int l = 0; l < 3; l++)
if ( (normals[el[l]] * nv) < 0.5)
bad2 += 1e10;
illegal2 += 1-mesh.LegalTrig(el);
}
bad2 /= hasonepi.Size();
mesh[pi1] = p1;
mesh[pi2] = p2;
if (debugflag)
{
(*testout) << "bad1 = " << bad1 << ", bad2 = " << bad2 << endl;
}
bool should = (bad2 < bad1 && bad2 < 1e4);
if (bad2 < 1e4)
{
if (illegal1 > illegal2) should = true;
if (illegal2 > illegal1) should = false;
}
if (should)
{
/*
(*testout) << "combine !" << endl;
(*testout) << "bad1 = " << bad1 << ", bad2 = " << bad2 << endl;
(*testout) << "illegal1 = " << illegal1 << ", illegal2 = " << illegal2 << endl;
(*testout) << "loch = " << loch << endl;
*/
mesh[pi1] = pnew;
PointGeomInfo gi;
// bool gi_set(false);
/*
Element2d *el1p(NULL);
int l = 0;
while(mesh[elementsonnode[pi1][l]].IsDeleted() && l<elementsonnode[pi1].Size()) l++;
if(l<elementsonnode[pi1].Size())
el1p = &mesh[elementsonnode[pi1][l]];
else
cerr << "OOPS!" << endl;
for (l = 0; l < el1p->GetNP(); l++)
if ((*el1p)[l] == pi1)
{
gi = el1p->GeomInfoPi (l+1);
// gi_set = true;
}
*/
for (SurfaceElementIndex sei : elementsonnode[pi1])
{
const Element2d & el1p = mesh[sei];
if (el1p.IsDeleted()) continue;
for (int l = 0; l < el1p.GetNP(); l++)
if (el1p[l] == pi1)
// gi = el1p.GeomInfoPi (l+1);
gi = el1p.GeomInfo()[l];
break;
}
// (*testout) << "Connect point " << pi2 << " to " << pi1 << "\n";
// for (int k = 0; k < elementsonnode[pi2].Size(); k++)
for (SurfaceElementIndex sei2 : elementsonnode[pi2])
{
Element2d & el = mesh[sei2];
if (el.IsDeleted()) continue;
if (el.PNums().Contains(pi1)) continue;
elementsonnode.Add (pi1, sei2);
for (auto l : Range(el.GetNP()))
{
if (el[l] == pi2)
{
el[l] = pi1;
el.GeomInfo()[l] = gi;
}
fixed[el[l]] = true;
}
}
for (auto sei : hasbothpi)
mesh[sei].Delete();
}
}
}
// mesh.Compress();
mesh.SetNextTimeStamp();
}
void MeshOptimize2d :: CheckMeshApproximation (Mesh & mesh)
{
// Check angles between elements and normals at corners
/*
int i, j;
int ne = mesh.GetNSE();
int surfnr;
Vec3d n, ng;
NgArray<Vec3d> ngs(3);
(*mycout) << "Check Surface Approximation" << endl;
(*testout) << "Check Surface Approximation" << endl;
for (i = 1; i <= ne; i++)
{
const Element2d & el = mesh.SurfaceElement(i);
surfnr = mesh.GetFaceDescriptor (el.GetIndex()).SurfNr();
Vec3d n = Cross (mesh.Point (el.PNum(1)) - mesh.Point (el.PNum(2)),
mesh.Point (el.PNum(1)) - mesh.Point (el.PNum(3)));
n /= n.Length();
for (j = 1; j <= el.GetNP(); j++)
{
SelectSurfaceOfPoint (mesh.Point(el.PNum(j)), el.GeomInfoPi(j));
GetNormalVector (surfnr, mesh.Point(el.PNum(j)), ng);
ng /= ng.Length();
ngs.Elem(j) = ng;
double angle = (180.0 / M_PI) * Angle (n, ng);
if (angle > 60)
{
(*testout) << "el " << i << " node " << el.PNum(j)
<< "has angle = " << angle << endl;
}
}
for (j = 1; j <= 3; j++)
{
double angle = (180.0 / M_PI) * Angle (ngs.Get(j), ngs.Get(j%3+1));
if (angle > 60)
{
(*testout) << "el " << i << " node-node "
<< ngs.Get(j) << " - " << ngs.Get(j%3+1)
<< " has angle = " << angle << endl;
}
}
}
*/
}
}