1 // ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
3 // + This file is part of enGrid. +
5 // + Copyright 2008-2014 enGits GmbH +
7 // + enGrid is free software: you can redistribute it and/or modify +
8 // + it under the terms of the GNU General Public License as published by +
9 // + the Free Software Foundation, either version 3 of the License, or +
10 // + (at your option) any later version. +
12 // + enGrid is distributed in the hope that it will be useful, +
13 // + but WITHOUT ANY WARRANTY; without even the implied warranty of +
14 // + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +
15 // + GNU General Public License for more details. +
17 // + You should have received a copy of the GNU General Public License +
18 // + along with enGrid. If not, see <http://www.gnu.org/licenses/>. +
20 // ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
21 #include "swaptriangles.h"
22 #include "guimainwindow.h"
24 #include <vtkCellArray.h>
26 #include "checksurfaceintegrity.h"
27 #include "statistics.h"
29 using namespace GeometryTools
;
31 SwapTriangles::SwapTriangles() : SurfaceOperation()
34 m_FeatureSwap
= false;
35 m_FeatureAngle
= GeometryTools::deg2rad(30);
37 m_SmallAreaSwap
= false;
38 m_SmallAreaRatio
= 1e-3;
40 m_DelaunayThreshold
= 1.0;
41 getSet("surface meshing", "small area ratio for edge-swapping", 1e-3, m_SmallAreaRatio
);
42 getSet("surface meshing", "surface error threshold", 0.05, m_SurfErrorThreshold
);
43 m_SurfErrorThreshold
= deg2rad(m_SurfErrorThreshold
);
46 bool SwapTriangles::testOrientation(stencil_t S
)
49 vec3_t n1_old
= triNormal(m_Grid
, S
.id_node
[0], S
.p1
, S
.p2
);
50 vec3_t n2_old
= triNormal(m_Grid
, S
.id_node
[1], S
.p2
, S
.p1
);
53 vec3_t n1_new
= triNormal(m_Grid
, S
.p1
, S
.id_node
[1], S
.id_node
[0]);
54 vec3_t n2_new
= triNormal(m_Grid
, S
.p2
, S
.id_node
[0], S
.id_node
[1]);
57 vec3_t
x_summit(0,0,0);
60 m_Grid
->GetPoints()->GetPoint(S
.id_node
[0], x
[0].data());
61 m_Grid
->GetPoints()->GetPoint(S
.p1
, x
[1].data());
62 m_Grid
->GetPoints()->GetPoint(S
.id_node
[1], x
[2].data());
63 m_Grid
->GetPoints()->GetPoint(S
.p2
, x
[3].data());
64 for (int k
= 0; k
< 4; ++k
) {
67 for (int k
= 0; k
< 4; ++k
) {
73 l_max
= max(l_max
, (x
[i
]-x
[j
]).abs());
76 vec3_t n
= n1_old
+ n2_old
;
78 x_summit
+= 3*l_max
*n
;
81 double V1_old
= tetraVol(x
[0], x
[1], x
[3], x_summit
, true);
82 double V2_old
= tetraVol(x
[2], x
[3], x
[1], x_summit
, true);
84 double V1_new
= tetraVol(x
[1], x
[2], x
[0], x_summit
, true);
85 double V2_new
= tetraVol(x
[3], x
[0], x
[2], x_summit
, true);
88 if (m_SmallAreaSwap
) {
89 swap_ok
= V1_new
>0 && V2_new
>0;
91 swap_ok
= V1_old
>0 && V2_old
>0 && V1_new
>0 && V2_new
>0;
96 bool SwapTriangles::isEdge(vtkIdType id_node1
, vtkIdType id_node2
)
98 l2g_t nodes
= getPartNodes();
99 g2l_t _nodes
= getPartLocalNodes();
100 l2l_t n2n
= getPartN2N();
103 foreach(int i_node
, n2n
[_nodes
[id_node1
]]) {
104 vtkIdType id_node
= nodes
[i_node
];
105 if( id_node
== id_node2
) ret
= true;
110 double SwapTriangles::computeSurfaceDistance(vec3_t x1
, vec3_t x2
, vec3_t x3
, CadInterface
*cad_interface
)
112 static const double f13
= 1.0/3.0;
113 vec3_t x
= f13
*(x1
+ x2
+ x3
);
114 vec3_t n
= triNormal(x1
, x2
, x3
);
116 if (!checkVector(n
)) {
119 vec3_t xp
= cad_interface
->snap(x
, false);
120 return (x
- xp
).abs();
123 double SwapTriangles::edgeAngle(vec3_t x1
, vec3_t x2
, vec3_t x3
, vec3_t x4
)
125 static const double f13
= 1.0/3.0;
126 vec3_t xf1
= f13
*(x1
+ x2
+ x4
);
127 vec3_t xf2
= f13
*(x2
+ x3
+ x4
);
128 vec3_t xe
= 0.5*(x2
+ x4
);
129 vec3_t xfe
= 0.5*(xf1
+ xf2
);
130 vec3_t n1
= triNormal(x1
, x2
, x4
);
131 vec3_t n2
= triNormal(x2
, x3
, x4
);
132 vec3_t ve
= xe
- xfe
;
133 double alpha
= angle(n1
, n2
);
134 if ((n1
+ n2
)*ve
< 0) {
140 vtkIdType
SwapTriangles::neighbourNode(vtkIdType id_node0
, vtkIdType id_node1
, vtkIdType id_node2
)
142 for (int i
= 0; i
< m_Part
.n2nGSize(id_node1
); ++i
) {
143 vtkIdType id_neigh
= m_Part
.n2nGG(id_node1
, i
);
144 if (id_neigh
!= id_node0
) {
145 if (m_Part
.hasNeighNode(id_node2
, id_neigh
)) {
154 bool SwapTriangles::swapDueToSurfaceNoise(stencil_t S
)
156 vtkIdType p1
= S
.id_node
[0];
158 vtkIdType p3
= S
.id_node
[1];
160 vtkIdType p12
= neighbourNode(p4
, p1
, p2
);
161 vtkIdType p23
= neighbourNode(p4
, p2
, p3
);
162 vtkIdType p34
= neighbourNode(p2
, p3
, p4
);
163 vtkIdType p41
= neighbourNode(p2
, p4
, p1
);
164 vec3_t x1
, x2
, x3
, x4
, x12
, x23
, x34
, x41
;
165 m_Grid
->GetPoint(p1
, x1
.data());
166 m_Grid
->GetPoint(p2
, x2
.data());
167 m_Grid
->GetPoint(p3
, x3
.data());
168 m_Grid
->GetPoint(p4
, x4
.data());
169 m_Grid
->GetPoint(p12
, x12
.data());
170 m_Grid
->GetPoint(p23
, x23
.data());
171 m_Grid
->GetPoint(p34
, x34
.data());
172 m_Grid
->GetPoint(p41
, x41
.data());
174 double noise1
, noise2
;
176 double alpha_min
= M_PI
;
177 double alpha_max
= -M_PI
;
180 alpha
= edgeAngle(x4
, x1
, x12
, x2
);
181 alpha_max
= max(alpha
, alpha_max
);
182 alpha_min
= min(alpha
, alpha_min
);
184 alpha
= edgeAngle(x4
, x2
, x23
, x3
);
185 alpha_max
= max(alpha
, alpha_max
);
186 alpha_min
= min(alpha
, alpha_min
);
188 alpha
= edgeAngle(x2
, x3
, x34
, x4
);
189 alpha_max
= max(alpha
, alpha_max
);
190 alpha_min
= min(alpha
, alpha_min
);
192 alpha
= edgeAngle(x2
, x4
, x41
, x1
);
193 alpha_max
= max(alpha
, alpha_max
);
194 alpha_min
= min(alpha
, alpha_min
);
196 alpha
= edgeAngle(x1
, x2
, x3
, x4
);
197 alpha_max
= max(alpha
, alpha_max
);
198 alpha_min
= min(alpha
, alpha_min
);
200 noise1
= alpha_max
- alpha_min
;
203 double alpha_min
= M_PI
;
204 double alpha_max
= -M_PI
;
207 alpha
= edgeAngle(x3
, x1
, x12
, x2
);
208 alpha_max
= max(alpha
, alpha_max
);
209 alpha_min
= min(alpha
, alpha_min
);
211 alpha
= edgeAngle(x1
, x2
, x23
, x3
);
212 alpha_max
= max(alpha
, alpha_max
);
213 alpha_min
= min(alpha
, alpha_min
);
215 alpha
= edgeAngle(x1
, x3
, x34
, x4
);
216 alpha_max
= max(alpha
, alpha_max
);
217 alpha_min
= min(alpha
, alpha_min
);
219 alpha
= edgeAngle(x3
, x4
, x41
, x1
);
220 alpha_max
= max(alpha
, alpha_max
);
221 alpha_min
= min(alpha
, alpha_min
);
223 alpha
= edgeAngle(x2
, x3
, x4
, x1
);
224 alpha_max
= max(alpha
, alpha_max
);
225 alpha_min
= min(alpha
, alpha_min
);
227 noise2
= alpha_max
- alpha_min
;
230 if (noise1
> m_SurfErrorThreshold
&& noise1
> noise2
) {
237 void SwapTriangles::computeSurfaceErrors(const QVector
<vec3_t
> &x
, int bc
, double &err1
, double &err2
)
239 using namespace GeometryTools
;
242 CadInterface
* cad_interface
= GuiMainWindow::pointer()->getCadInterface(bc
);
243 if (!cad_interface
) {
247 double d013
= computeSurfaceDistance(x
[0], x
[1], x
[3], cad_interface
);
248 double d123
= computeSurfaceDistance(x
[1], x
[2], x
[3], cad_interface
);
249 double d012
= computeSurfaceDistance(x
[0], x
[1], x
[2], cad_interface
);
250 double d023
= computeSurfaceDistance(x
[0], x
[2], x
[3], cad_interface
);
252 double L
= max((x
[1] - x
[3]).abs(), (x
[0] - x
[2]).abs());
253 err1
= max(d013
, d123
)/L
;
254 err2
= max(d012
, d023
)/L
;
255 if (err1
< m_SurfErrorThreshold
) {
258 if (err2
< m_SurfErrorThreshold
) {
264 int SwapTriangles::swap()
267 setAllSurfaceCells();
268 //computeAverageSurfaceError();
269 EG_VTKDCC(vtkIntArray
, cell_code
, m_Grid
, "cell_code");
270 EG_VTKDCN(vtkCharArray
, node_type
, m_Grid
, "node_type");
271 QVector
<bool> marked(m_Grid
->GetNumberOfCells(), false);
272 for (int i
= 0; i
< m_Part
.getNumberOfCells(); ++i
) {
273 vtkIdType id_cell
= m_Part
.globalCell(i
);
274 if (!m_BoundaryCodes
.contains(cell_code
->GetValue(id_cell
)) && m_Grid
->GetCellType(id_cell
) == VTK_TRIANGLE
) { //if it is a selected triangle
275 if (!marked
[id_cell
] && !m_Swapped
[id_cell
]) {
276 for (int j
= 0; j
< 3; ++j
) {
278 stencil_t S
= getStencil(id_cell
, j
);
279 if(S
.id_cell
.size() == 2 && S
.sameBC
) {
280 if (S
.type_cell
[1] == VTK_TRIANGLE
) {
281 if(!isEdge(S
.id_node
[0], S
.id_node
[1]) ) {
282 //if (!marked[S.id_cell[1]] && !m_Swapped[S.id_cell[1]] && (!isFeatureNode(S.id_node[0]) || !isFeatureNode(S.id_node[1]))) {
283 if (!marked
[S
.id_cell
[1]] && !m_Swapped
[S
.id_cell
[1]] && (!isFeatureNode(S
.p1
) || !isFeatureNode(S
.p2
))) {
284 QVector
<vec3_t
> x3(4);
287 m_Grid
->GetPoint(S
.id_node
[0], x3
[0].data());
288 m_Grid
->GetPoint(S
.p1
, x3
[1].data());
289 m_Grid
->GetPoint(S
.id_node
[1], x3
[2].data());
290 m_Grid
->GetPoint(S
.p2
, x3
[3].data());
292 vec3_t n1
= triNormal(x3
[0], x3
[1], x3
[3]);
293 vec3_t n2
= triNormal(x3
[1], x3
[2], x3
[3]);
295 if (m_SmallAreaSwap
) {
296 double A1
= n1
.abs();
297 double A2
= n2
.abs();
298 if (isnan(A1
) || isnan(A2
)) {
301 swap
= A1
< m_SmallAreaRatio
*A2
|| A2
< m_SmallAreaRatio
*A1
;
305 if (GeometryTools::angle(n1
, n2
) < m_FeatureAngle
) {
311 vec3_t ex
= orthogonalVector(n
);
312 vec3_t ey
= ex
.cross(n
);
313 for (int k
= 0; k
< 4; ++k
) {
314 x
[k
] = vec2_t(x3
[k
]*ex
, x3
[k
]*ey
);
316 vec2_t r1
, r2
, r3
, u1
, u2
, u3
;
317 r1
= 0.5*(x
[0] + x
[1]); u1
= turnLeft(x
[1] - x
[0]);
318 r2
= 0.5*(x
[1] + x
[2]); u2
= turnLeft(x
[2] - x
[1]);
319 r3
= 0.5*(x
[1] + x
[3]); u3
= turnLeft(x
[3] - x
[1]);
323 if (intersection(k
, l
, r1
, u1
, r3
, u3
)) {
325 if (intersection(k
, l
, r2
, u2
, r3
, u3
)) {
335 if ((xm1
- x
[2]).abs() < (xm1
- x
[0]).abs()/m_DelaunayThreshold
) {
338 if ((xm2
- x
[0]).abs() < (xm2
- x
[2]).abs()/m_DelaunayThreshold
) {
343 } //end of if feature angle
344 } //end of if l_marked
345 } //end of if TestSwap
350 if (testOrientation(S
)) {
351 marked
[S
.id_cell
[0]] = true;
352 marked
[S
.id_cell
[1]] = true;
353 for (int k
= 0; k
< m_Part
.n2cGSize(S
.id_node
[0]); ++k
) {
354 vtkIdType id_neigh
= m_Part
.n2cGG(S
.id_node
[0], k
);
355 marked
[id_neigh
] = true;
357 for (int k
= 0; k
< m_Part
.n2cGSize(S
.id_node
[1]); ++k
) {
358 vtkIdType id_neigh
= m_Part
.n2cGG(S
.id_node
[1], k
);
359 marked
[id_neigh
] = true;
361 for (int k
= 0; k
< m_Part
.n2cGSize(S
.p1
); ++k
) {
362 vtkIdType id_neigh
= m_Part
.n2cGG(S
.p1
, k
);
363 marked
[id_neigh
] = true;
365 for (int k
= 0; k
< m_Part
.n2cGSize(S
.p2
); ++k
) {
366 vtkIdType id_neigh
= m_Part
.n2cGG(S
.p2
, k
);
367 marked
[id_neigh
] = true;
369 vtkIdType new_pts1
[3], new_pts2
[3];
371 new_pts1
[1] = S
.id_node
[1];
372 new_pts1
[2] = S
.id_node
[0];
373 new_pts2
[0] = S
.id_node
[1];
375 new_pts2
[2] = S
.id_node
[0];
376 vtkIdType old_pts1
[3], old_pts2
[3];
377 old_pts1
[0] = S
.id_node
[0];
380 old_pts2
[0] = S
.id_node
[1];
383 m_Grid
->ReplaceCell(S
.id_cell
[0], 3, new_pts1
);
384 m_Grid
->ReplaceCell(S
.id_cell
[1], 3, new_pts2
);
385 m_Swapped
[S
.id_cell
[0]] = true;
386 m_Swapped
[S
.id_cell
[1]] = true;
391 } //end of loop through sides
393 } //end of if selected triangle
394 } //end of loop through cells
398 void SwapTriangles::computeAverageSurfaceError()
400 EG_VTKDCC(vtkIntArray
, cell_code
, m_Grid
, "cell_code");
401 QList
<double> errors
;
402 EG_FORALL_NODES(id_node1
, m_Grid
) {
403 vec3_t n1
= m_Part
.globalNormal(id_node1
);
405 m_Grid
->GetPoint(id_node1
, x1
.data());
406 for (int i
= 0; i
< m_Part
.n2nGSize(id_node1
); ++i
) {
407 vtkIdType id_node2
= m_Part
.n2nGG(id_node1
, i
);
408 if (id_node1
< id_node2
) {
409 QVector
<vtkIdType
> faces
;
410 getEdgeCells(id_node1
, id_node2
, faces
);
411 if (faces
.size() == 2) {
412 int bc1
= cell_code
->GetValue(faces
[0]);
413 int bc2
= cell_code
->GetValue(faces
[1]);
415 CadInterface
* cad_interface
= GuiMainWindow::pointer()->getCadInterface(bc1
);
417 vec3_t n2
= m_Part
.globalNormal(id_node2
);
418 vec3_t n
= 0.5*(n1
+ n2
);
420 m_Grid
->GetPoint(id_node2
, x2
.data());
421 vec3_t x
= 0.5*(x1
+ x2
);
422 vec3_t xp
= cad_interface
->snap(x
);
423 double err
= (x
- xp
).abs()/(x1
- x2
).abs();
432 m_AverageSurfaceError
= Statistics::meanValue(errors
);
433 m_SurfaceErrorDeviation
= Statistics::standardDeviation(errors
, m_AverageSurfaceError
);
434 cout
<< "mean: " << m_AverageSurfaceError
<< " sigma: " << m_SurfaceErrorDeviation
<< endl
;
437 void SwapTriangles::operate()
439 if (m_Verbose
) cout
<< "swapping edges for surface triangles ..." << endl
;
440 long int N_swaps
= 100000000;
441 long int N_last_swaps
= 100000001;
444 while ((N_swaps
> 0) && (loop
<= m_MaxNumLoops
) && (N_swaps
< N_last_swaps
)) {
445 N_last_swaps
= N_swaps
;
446 if (m_Verbose
) cout
<< " loop " << loop
<< "/" << m_MaxNumLoops
<< endl
;
447 m_Swapped
.fill(false, m_Grid
->GetNumberOfCells());
454 m_NumSwaps
= max(N
, m_NumSwaps
);
455 if (m_Verbose
) cout
<< " sub-loop " << sub_loop
<< ": " << N
<< " swaps" << endl
;