xref: /petsc/src/dm/impls/swarm/swarmpic_plex.c (revision 6f150b4d0a4003fa79fe091e32a8eb069c7d15a1)
1 #include <petscdm.h>
2 #include <petscdmplex.h>
3 #include <petscdmswarm.h>
4 #include "data_bucket.h"
5 
6 
7 PetscErrorCode private_DMSwarmSetPointCoordinatesCellwise_PLEX(DM,DM,PetscInt,PetscReal*xi);
8 
9 static PetscErrorCode private_PetscFECreateDefault_scalar_pk1(DM dm, PetscInt dim, PetscBool isSimplex, PetscInt qorder, PetscFE *fem)
10 {
11   const PetscInt Nc = 1;
12   PetscQuadrature q, fq;
13   DM              K;
14   PetscSpace      P;
15   PetscDualSpace  Q;
16   PetscInt        order, quadPointsPerEdge;
17   PetscBool       tensor = isSimplex ? PETSC_FALSE : PETSC_TRUE;
18   PetscErrorCode  ierr;
19 
20   PetscFunctionBegin;
21   /* Create space */
22   ierr = PetscSpaceCreate(PetscObjectComm((PetscObject) dm), &P);CHKERRQ(ierr);
23   /*ierr = PetscObjectSetOptionsPrefix((PetscObject) P, prefix);CHKERRQ(ierr);*/
24   ierr = PetscSpacePolynomialSetTensor(P, tensor);CHKERRQ(ierr);
25   /*ierr = PetscSpaceSetFromOptions(P);CHKERRQ(ierr);*/
26   ierr = PetscSpaceSetType(P,PETSCSPACEPOLYNOMIAL);CHKERRQ(ierr);
27   ierr = PetscSpaceSetOrder(P,1);CHKERRQ(ierr);
28   ierr = PetscSpaceSetNumComponents(P, Nc);CHKERRQ(ierr);
29   ierr = PetscSpacePolynomialSetNumVariables(P, dim);CHKERRQ(ierr);
30   ierr = PetscSpaceSetUp(P);CHKERRQ(ierr);
31   ierr = PetscSpaceGetOrder(P, &order);CHKERRQ(ierr);
32   ierr = PetscSpacePolynomialGetTensor(P, &tensor);CHKERRQ(ierr);
33   /* Create dual space */
34   ierr = PetscDualSpaceCreate(PetscObjectComm((PetscObject) dm), &Q);CHKERRQ(ierr);
35   ierr = PetscDualSpaceSetType(Q,PETSCDUALSPACELAGRANGE);CHKERRQ(ierr);
36   /*ierr = PetscObjectSetOptionsPrefix((PetscObject) Q, prefix);CHKERRQ(ierr);*/
37   ierr = PetscDualSpaceCreateReferenceCell(Q, dim, isSimplex, &K);CHKERRQ(ierr);
38   ierr = PetscDualSpaceSetDM(Q, K);CHKERRQ(ierr);
39   ierr = DMDestroy(&K);CHKERRQ(ierr);
40   ierr = PetscDualSpaceSetNumComponents(Q, Nc);CHKERRQ(ierr);
41   ierr = PetscDualSpaceSetOrder(Q, order);CHKERRQ(ierr);
42   ierr = PetscDualSpaceLagrangeSetTensor(Q, tensor);CHKERRQ(ierr);
43   /*ierr = PetscDualSpaceSetFromOptions(Q);CHKERRQ(ierr);*/
44   ierr = PetscDualSpaceSetType(Q,PETSCDUALSPACELAGRANGE);CHKERRQ(ierr);
45   ierr = PetscDualSpaceSetUp(Q);CHKERRQ(ierr);
46   /* Create element */
47   ierr = PetscFECreate(PetscObjectComm((PetscObject) dm), fem);CHKERRQ(ierr);
48   /*ierr = PetscObjectSetOptionsPrefix((PetscObject) *fem, prefix);CHKERRQ(ierr);*/
49   /*ierr = PetscFESetFromOptions(*fem);CHKERRQ(ierr);*/
50   ierr = PetscFESetType(*fem,PETSCFEBASIC);CHKERRQ(ierr);
51   ierr = PetscFESetBasisSpace(*fem, P);CHKERRQ(ierr);
52   ierr = PetscFESetDualSpace(*fem, Q);CHKERRQ(ierr);
53   ierr = PetscFESetNumComponents(*fem, Nc);CHKERRQ(ierr);
54   ierr = PetscFESetUp(*fem);CHKERRQ(ierr);
55   ierr = PetscSpaceDestroy(&P);CHKERRQ(ierr);
56   ierr = PetscDualSpaceDestroy(&Q);CHKERRQ(ierr);
57   /* Create quadrature (with specified order if given) */
58   qorder = qorder >= 0 ? qorder : order;
59   quadPointsPerEdge = PetscMax(qorder + 1,1);
60   if (isSimplex) {
61     ierr = PetscDTGaussJacobiQuadrature(dim,   1, quadPointsPerEdge, -1.0, 1.0, &q);CHKERRQ(ierr);
62     ierr = PetscDTGaussJacobiQuadrature(dim-1, 1, quadPointsPerEdge, -1.0, 1.0, &fq);CHKERRQ(ierr);
63   }
64   else {
65     ierr = PetscDTGaussTensorQuadrature(dim,   1, quadPointsPerEdge, -1.0, 1.0, &q);CHKERRQ(ierr);
66     ierr = PetscDTGaussTensorQuadrature(dim-1, 1, quadPointsPerEdge, -1.0, 1.0, &fq);CHKERRQ(ierr);
67   }
68   ierr = PetscFESetQuadrature(*fem, q);CHKERRQ(ierr);
69   ierr = PetscFESetFaceQuadrature(*fem, fq);CHKERRQ(ierr);
70   ierr = PetscQuadratureDestroy(&q);CHKERRQ(ierr);
71   ierr = PetscQuadratureDestroy(&fq);CHKERRQ(ierr);
72   PetscFunctionReturn(0);
73 }
74 
75 PetscErrorCode subdivide_triangle(PetscReal v1[2],PetscReal v2[2],PetscReal v3[3],PetscInt depth,PetscInt max,PetscReal xi[],PetscInt *np)
76 {
77   PetscReal v12[2],v23[2],v31[2];
78   PetscInt i;
79   PetscErrorCode ierr;
80 
81   PetscFunctionBegin;
82   if (depth == max) {
83     PetscReal cx[2];
84 
85     cx[0] = (v1[0] + v2[0] + v3[0])/3.0;
86     cx[1] = (v1[1] + v2[1] + v3[1])/3.0;
87 
88     xi[2*(*np)+0] = cx[0];
89     xi[2*(*np)+1] = cx[1];
90     (*np)++;
91     PetscFunctionReturn(0);
92   }
93 
94   /* calculate midpoints of each side */
95   for (i = 0; i < 2; i++) {
96     v12[i] = (v1[i]+v2[i])/2.0;
97     v23[i] = (v2[i]+v3[i])/2.0;
98     v31[i] = (v3[i]+v1[i])/2.0;
99   }
100 
101   /* recursively subdivide new triangles */
102   ierr = subdivide_triangle(v1,v12,v31,depth+1,max,xi,np);CHKERRQ(ierr);
103   ierr = subdivide_triangle(v2,v23,v12,depth+1,max,xi,np);CHKERRQ(ierr);
104   ierr = subdivide_triangle(v3,v31,v23,depth+1,max,xi,np);CHKERRQ(ierr);
105   ierr = subdivide_triangle(v12,v23,v31,depth+1,max,xi,np);CHKERRQ(ierr);
106   PetscFunctionReturn(0);
107 }
108 
109 
110 PetscErrorCode private_DMSwarmInsertPointsUsingCellDM_PLEX2D_SubDivide(DM dm,DM dmc,PetscInt nsub)
111 {
112   PetscErrorCode ierr;
113   const PetscInt dim = 2;
114   PetscInt q,npoints_q,e,nel,npe,pcnt,ps,pe,d,k,depth;
115   PetscReal *xi;
116   PetscReal **basis;
117   Vec coorlocal;
118   PetscSection coordSection;
119   PetscScalar *elcoor = NULL;
120   PetscReal *swarm_coor;
121   PetscInt *swarm_cellid;
122   PetscReal v1[2],v2[2],v3[2];
123 
124   PetscFunctionBegin;
125 
126   npoints_q = 1;
127   for (d=0; d<nsub; d++) { npoints_q *= 4; }
128   ierr = PetscMalloc1(dim*npoints_q,&xi);CHKERRQ(ierr);
129 
130   v1[0] = 0.0;  v1[1] = 0.0;
131   v2[0] = 1.0;  v2[1] = 0.0;
132   v3[0] = 0.0;  v3[1] = 1.0;
133   depth = 0;
134   pcnt = 0;
135   ierr = subdivide_triangle(v1,v2,v3,depth,nsub,xi,&pcnt);CHKERRQ(ierr);
136 
137   npe = 3; /* nodes per element (triangle) */
138   ierr = PetscMalloc1(npoints_q,&basis);CHKERRQ(ierr);
139   for (q=0; q<npoints_q; q++) {
140     ierr = PetscMalloc1(npe,&basis[q]);CHKERRQ(ierr);
141 
142     basis[q][0] = 1.0 - xi[dim*q+0] - xi[dim*q+1];
143     basis[q][1] = xi[dim*q+0];
144     basis[q][2] = xi[dim*q+1];
145   }
146 
147   /* 0->cell, 1->edge, 2->vert */
148   ierr = DMPlexGetHeightStratum(dmc,0,&ps,&pe);CHKERRQ(ierr);
149   nel = pe - ps;
150 
151   ierr = DMSwarmSetLocalSizes(dm,npoints_q*nel,-1);CHKERRQ(ierr);
152   ierr = DMSwarmGetField(dm,DMSwarmPICField_coor,NULL,NULL,(void**)&swarm_coor);CHKERRQ(ierr);
153   ierr = DMSwarmGetField(dm,DMSwarmPICField_cellid,NULL,NULL,(void**)&swarm_cellid);CHKERRQ(ierr);
154 
155   ierr = DMGetCoordinatesLocal(dmc,&coorlocal);CHKERRQ(ierr);
156   ierr = DMGetCoordinateSection(dmc,&coordSection);CHKERRQ(ierr);
157 
158   pcnt = 0;
159   for (e=0; e<nel; e++) {
160     ierr = DMPlexVecGetClosure(dmc,coordSection,coorlocal,e,NULL,&elcoor);CHKERRQ(ierr);
161 
162     for (q=0; q<npoints_q; q++) {
163       for (d=0; d<dim; d++) {
164         swarm_coor[dim*pcnt+d] = 0.0;
165         for (k=0; k<npe; k++) {
166           swarm_coor[dim*pcnt+d] += basis[q][k] * PetscRealPart(elcoor[dim*k+d]);
167         }
168       }
169       swarm_cellid[pcnt] = e;
170       pcnt++;
171     }
172     ierr = DMPlexVecRestoreClosure(dmc,coordSection,coorlocal,e,NULL,&elcoor);CHKERRQ(ierr);
173   }
174   ierr = DMSwarmRestoreField(dm,DMSwarmPICField_cellid,NULL,NULL,(void**)&swarm_cellid);CHKERRQ(ierr);
175   ierr = DMSwarmRestoreField(dm,DMSwarmPICField_coor,NULL,NULL,(void**)&swarm_coor);CHKERRQ(ierr);
176 
177   ierr = PetscFree(xi);CHKERRQ(ierr);
178   for (q=0; q<npoints_q; q++) {
179     ierr = PetscFree(basis[q]);CHKERRQ(ierr);
180   }
181   ierr = PetscFree(basis);CHKERRQ(ierr);
182 
183   PetscFunctionReturn(0);
184 }
185 
186 PetscErrorCode private_DMSwarmInsertPointsUsingCellDM_PLEX_SubDivide(DM dm,DM dmc,PetscInt nsub)
187 {
188   PetscErrorCode ierr;
189   PetscInt dim,nfaces,nbasis;
190   PetscInt q,npoints_q,e,nel,pcnt,ps,pe,d,k,r;
191   PetscReal *B;
192   Vec coorlocal;
193   PetscSection coordSection;
194   PetscScalar *elcoor = NULL;
195   PetscReal *swarm_coor;
196   PetscInt *swarm_cellid;
197   const PetscReal *xiq;
198   PetscQuadrature quadrature;
199   PetscFE fe,feRef;
200   PetscBool is_simplex;
201 
202   PetscFunctionBegin;
203 
204   ierr = DMGetDimension(dmc,&dim);CHKERRQ(ierr);
205 
206   is_simplex = PETSC_FALSE;
207   ierr = DMPlexGetHeightStratum(dmc,0,&ps,&pe);CHKERRQ(ierr);
208   ierr = DMPlexGetConeSize(dmc, ps, &nfaces);CHKERRQ(ierr);
209   if (nfaces == (dim+1)) { is_simplex = PETSC_TRUE; }
210 
211   ierr = private_PetscFECreateDefault_scalar_pk1(dmc, dim, is_simplex, 0, &fe);CHKERRQ(ierr);
212 
213   for (r=0; r<nsub; r++) {
214     ierr = PetscFERefine(fe,&feRef);CHKERRQ(ierr);
215     ierr = PetscFEGetQuadrature(feRef,&quadrature);CHKERRQ(ierr);
216     ierr = PetscFESetQuadrature(fe,quadrature);CHKERRQ(ierr);
217     ierr = PetscFEDestroy(&feRef);CHKERRQ(ierr);
218   }
219 
220   ierr = PetscFEGetQuadrature(fe,&quadrature);CHKERRQ(ierr);
221   ierr = PetscQuadratureGetData(quadrature, NULL, NULL, &npoints_q, &xiq, NULL);CHKERRQ(ierr);
222   ierr = PetscFEGetDimension(fe,&nbasis);CHKERRQ(ierr);
223   ierr = PetscFEGetDefaultTabulation(fe, &B, NULL, NULL);CHKERRQ(ierr);
224 
225   /* 0->cell, 1->edge, 2->vert */
226   ierr = DMPlexGetHeightStratum(dmc,0,&ps,&pe);CHKERRQ(ierr);
227   nel = pe - ps;
228 
229   ierr = DMSwarmSetLocalSizes(dm,npoints_q*nel,-1);CHKERRQ(ierr);
230   ierr = DMSwarmGetField(dm,DMSwarmPICField_coor,NULL,NULL,(void**)&swarm_coor);CHKERRQ(ierr);
231   ierr = DMSwarmGetField(dm,DMSwarmPICField_cellid,NULL,NULL,(void**)&swarm_cellid);CHKERRQ(ierr);
232 
233   ierr = DMGetCoordinatesLocal(dmc,&coorlocal);CHKERRQ(ierr);
234   ierr = DMGetCoordinateSection(dmc,&coordSection);CHKERRQ(ierr);
235 
236   pcnt = 0;
237   for (e=0; e<nel; e++) {
238     ierr = DMPlexVecGetClosure(dmc,coordSection,coorlocal,ps+e,NULL,&elcoor);CHKERRQ(ierr);
239 
240     for (q=0; q<npoints_q; q++) {
241       for (d=0; d<dim; d++) {
242         swarm_coor[dim*pcnt+d] = 0.0;
243         for (k=0; k<nbasis; k++) {
244           swarm_coor[dim*pcnt+d] += B[q*nbasis + k] * PetscRealPart(elcoor[dim*k+d]);
245         }
246       }
247       swarm_cellid[pcnt] = e;
248       pcnt++;
249     }
250     ierr = DMPlexVecRestoreClosure(dmc,coordSection,coorlocal,ps+e,NULL,&elcoor);CHKERRQ(ierr);
251   }
252   ierr = DMSwarmRestoreField(dm,DMSwarmPICField_cellid,NULL,NULL,(void**)&swarm_cellid);CHKERRQ(ierr);
253   ierr = DMSwarmRestoreField(dm,DMSwarmPICField_coor,NULL,NULL,(void**)&swarm_coor);CHKERRQ(ierr);
254 
255   ierr = PetscFEDestroy(&fe);CHKERRQ(ierr);
256   PetscFunctionReturn(0);
257 }
258 
259 PetscErrorCode private_DMSwarmInsertPointsUsingCellDM_PLEX2D_Regular(DM dm,DM dmc,PetscInt npoints)
260 {
261   PetscErrorCode ierr;
262   const PetscInt dim = 2;
263   PetscInt ii,jj,q,npoints_q,e,nel,npe,pcnt,ps,pe,d,k;
264   PetscReal *xi,ds,ds2;
265   PetscReal **basis;
266   Vec coorlocal;
267   PetscSection coordSection;
268   PetscScalar *elcoor = NULL;
269   PetscReal *swarm_coor;
270   PetscInt *swarm_cellid;
271 
272   PetscFunctionBegin;
273   ierr = PetscMalloc1(dim*npoints*npoints,&xi);CHKERRQ(ierr);
274   pcnt = 0;
275   ds = 1.0/((PetscReal)(npoints-1));
276   ds2 = 1.0/((PetscReal)(npoints));
277   for (jj = 0; jj<npoints; jj++) {
278     for (ii=0; ii<npoints-jj; ii++) {
279       xi[dim*pcnt+0] = ii * ds;
280       xi[dim*pcnt+1] = jj * ds;
281 
282       xi[dim*pcnt+0] *= (1.0 - 1.2*ds2);
283       xi[dim*pcnt+1] *= (1.0 - 1.2*ds2);
284 
285       xi[dim*pcnt+0] += 0.35*ds2;
286       xi[dim*pcnt+1] += 0.35*ds2;
287 
288       pcnt++;
289     }
290   }
291   npoints_q = pcnt;
292 
293   npe = 3; /* nodes per element (triangle) */
294   ierr = PetscMalloc1(npoints_q,&basis);CHKERRQ(ierr);
295   for (q=0; q<npoints_q; q++) {
296     ierr = PetscMalloc1(npe,&basis[q]);CHKERRQ(ierr);
297 
298     basis[q][0] = 1.0 - xi[dim*q+0] - xi[dim*q+1];
299     basis[q][1] = xi[dim*q+0];
300     basis[q][2] = xi[dim*q+1];
301   }
302 
303   /* 0->cell, 1->edge, 2->vert */
304   ierr = DMPlexGetHeightStratum(dmc,0,&ps,&pe);CHKERRQ(ierr);
305   nel = pe - ps;
306 
307   ierr = DMSwarmSetLocalSizes(dm,npoints_q*nel,-1);CHKERRQ(ierr);
308   ierr = DMSwarmGetField(dm,DMSwarmPICField_coor,NULL,NULL,(void**)&swarm_coor);CHKERRQ(ierr);
309   ierr = DMSwarmGetField(dm,DMSwarmPICField_cellid,NULL,NULL,(void**)&swarm_cellid);CHKERRQ(ierr);
310 
311   ierr = DMGetCoordinatesLocal(dmc,&coorlocal);CHKERRQ(ierr);
312   ierr = DMGetCoordinateSection(dmc,&coordSection);CHKERRQ(ierr);
313 
314   pcnt = 0;
315   for (e=0; e<nel; e++) {
316     ierr = DMPlexVecGetClosure(dmc,coordSection,coorlocal,e,NULL,&elcoor);CHKERRQ(ierr);
317 
318     for (q=0; q<npoints_q; q++) {
319       for (d=0; d<dim; d++) {
320         swarm_coor[dim*pcnt+d] = 0.0;
321         for (k=0; k<npe; k++) {
322           swarm_coor[dim*pcnt+d] += basis[q][k] * PetscRealPart(elcoor[dim*k+d]);
323         }
324       }
325       swarm_cellid[pcnt] = e;
326       pcnt++;
327     }
328     ierr = DMPlexVecRestoreClosure(dmc,coordSection,coorlocal,e,NULL,&elcoor);CHKERRQ(ierr);
329   }
330   ierr = DMSwarmRestoreField(dm,DMSwarmPICField_cellid,NULL,NULL,(void**)&swarm_cellid);CHKERRQ(ierr);
331   ierr = DMSwarmRestoreField(dm,DMSwarmPICField_coor,NULL,NULL,(void**)&swarm_coor);CHKERRQ(ierr);
332 
333   ierr = PetscFree(xi);CHKERRQ(ierr);
334   for (q=0; q<npoints_q; q++) {
335     ierr = PetscFree(basis[q]);CHKERRQ(ierr);
336   }
337   ierr = PetscFree(basis);CHKERRQ(ierr);
338 
339   PetscFunctionReturn(0);
340 }
341 
342 PetscErrorCode private_DMSwarmInsertPointsUsingCellDM_PLEX(DM dm,DM celldm,DMSwarmPICLayoutType layout,PetscInt layout_param)
343 {
344   PetscErrorCode ierr;
345   PetscInt dim;
346 
347   PetscFunctionBegin;
348   ierr = DMGetDimension(celldm,&dim);CHKERRQ(ierr);
349   switch (layout) {
350     case DMSWARMPIC_LAYOUT_REGULAR:
351       if (dim == 3) SETERRQ(PetscObjectComm((PetscObject)dm),PETSC_ERR_SUP,"No 3D support for REGULAR+PLEX");
352       ierr = private_DMSwarmInsertPointsUsingCellDM_PLEX2D_Regular(dm,celldm,layout_param);CHKERRQ(ierr);
353       break;
354     case DMSWARMPIC_LAYOUT_GAUSS:
355     {
356       PetscInt npoints,npoints1,ps,pe,nfaces;
357       const PetscReal *xi;
358       PetscBool is_simplex;
359       PetscQuadrature quadrature;
360 
361       is_simplex = PETSC_FALSE;
362       ierr = DMPlexGetHeightStratum(celldm,0,&ps,&pe);CHKERRQ(ierr);
363       ierr = DMPlexGetConeSize(celldm, ps, &nfaces);CHKERRQ(ierr);
364       if (nfaces == (dim+1)) { is_simplex = PETSC_TRUE; }
365 
366       npoints1 = layout_param;
367       if (is_simplex) {
368         ierr = PetscDTGaussJacobiQuadrature(dim,1,npoints1,-1.0,1.0,&quadrature);CHKERRQ(ierr);
369       } else {
370         ierr = PetscDTGaussTensorQuadrature(dim,1,npoints1,-1.0,1.0,&quadrature);CHKERRQ(ierr);
371       }
372       ierr = PetscQuadratureGetData(quadrature,NULL,NULL,&npoints,&xi,NULL);CHKERRQ(ierr);
373       ierr = private_DMSwarmSetPointCoordinatesCellwise_PLEX(dm,celldm,npoints,(PetscReal*)xi);CHKERRQ(ierr);
374       ierr = PetscQuadratureDestroy(&quadrature);CHKERRQ(ierr);
375     }
376       break;
377     case DMSWARMPIC_LAYOUT_SUBDIVISION:
378       ierr = private_DMSwarmInsertPointsUsingCellDM_PLEX_SubDivide(dm,celldm,layout_param);CHKERRQ(ierr);
379       break;
380   }
381   PetscFunctionReturn(0);
382 }
383 
384 /*
385 typedef struct {
386   PetscReal x,y;
387 } Point2d;
388 
389 static PetscErrorCode signp2d(Point2d p1, Point2d p2, Point2d p3,PetscReal *s)
390 {
391   PetscFunctionBegin;
392   *s = (p1.x - p3.x) * (p2.y - p3.y) - (p2.x - p3.x) * (p1.y - p3.y);
393   PetscFunctionReturn(0);
394 }
395 */
396 /*
397 static PetscErrorCode PointInTriangle(Point2d pt, Point2d v1, Point2d v2, Point2d v3,PetscBool *v)
398 {
399   PetscReal s1,s2,s3;
400   PetscBool b1, b2, b3;
401 
402   PetscFunctionBegin;
403   signp2d(pt, v1, v2,&s1); b1 = s1 < 0.0f;
404   signp2d(pt, v2, v3,&s2); b2 = s2 < 0.0f;
405   signp2d(pt, v3, v1,&s3); b3 = s3 < 0.0f;
406 
407   *v = ((b1 == b2) && (b2 == b3));
408   PetscFunctionReturn(0);
409 }
410 */
411 /*
412 static PetscErrorCode _ComputeLocalCoordinateAffine2d(PetscReal xp[],PetscReal coords[],PetscReal xip[],PetscReal *dJ)
413 {
414   PetscReal x1,y1,x2,y2,x3,y3;
415   PetscReal c,b[2],A[2][2],inv[2][2],detJ,od;
416 
417   PetscFunctionBegin;
418   x1 = coords[2*0+0];
419   x2 = coords[2*1+0];
420   x3 = coords[2*2+0];
421 
422   y1 = coords[2*0+1];
423   y2 = coords[2*1+1];
424   y3 = coords[2*2+1];
425 
426   c = x1 - 0.5*x1 - 0.5*x1 + 0.5*x2 + 0.5*x3;
427   b[0] = xp[0] - c;
428   c = y1 - 0.5*y1 - 0.5*y1 + 0.5*y2 + 0.5*y3;
429   b[1] = xp[1] - c;
430 
431   A[0][0] = -0.5*x1 + 0.5*x2;   A[0][1] = -0.5*x1 + 0.5*x3;
432   A[1][0] = -0.5*y1 + 0.5*y2;   A[1][1] = -0.5*y1 + 0.5*y3;
433 
434   detJ = A[0][0]*A[1][1] - A[0][1]*A[1][0];
435   *dJ = PetscAbsReal(detJ);
436   od = 1.0/detJ;
437 
438   inv[0][0] =  A[1][1] * od;
439   inv[0][1] = -A[0][1] * od;
440   inv[1][0] = -A[1][0] * od;
441   inv[1][1] =  A[0][0] * od;
442 
443   xip[0] = inv[0][0]*b[0] + inv[0][1]*b[1];
444   xip[1] = inv[1][0]*b[0] + inv[1][1]*b[1];
445   PetscFunctionReturn(0);
446 }
447 */
448 
449 static PetscErrorCode ComputeLocalCoordinateAffine2d(PetscReal xp[],PetscScalar coords[],PetscReal xip[],PetscReal *dJ)
450 {
451   PetscReal x1,y1,x2,y2,x3,y3;
452   PetscReal b[2],A[2][2],inv[2][2],detJ,od;
453 
454   PetscFunctionBegin;
455   x1 = PetscRealPart(coords[2*0+0]);
456   x2 = PetscRealPart(coords[2*1+0]);
457   x3 = PetscRealPart(coords[2*2+0]);
458 
459   y1 = PetscRealPart(coords[2*0+1]);
460   y2 = PetscRealPart(coords[2*1+1]);
461   y3 = PetscRealPart(coords[2*2+1]);
462 
463   b[0] = xp[0] - x1;
464   b[1] = xp[1] - y1;
465 
466   A[0][0] = x2-x1;   A[0][1] = x3-x1;
467   A[1][0] = y2-y1;   A[1][1] = y3-y1;
468 
469   detJ = A[0][0]*A[1][1] - A[0][1]*A[1][0];
470   *dJ = PetscAbsReal(detJ);
471   od = 1.0/detJ;
472 
473   inv[0][0] =  A[1][1] * od;
474   inv[0][1] = -A[0][1] * od;
475   inv[1][0] = -A[1][0] * od;
476   inv[1][1] =  A[0][0] * od;
477 
478   xip[0] = inv[0][0]*b[0] + inv[0][1]*b[1];
479   xip[1] = inv[1][0]*b[0] + inv[1][1]*b[1];
480   PetscFunctionReturn(0);
481 }
482 
483 PetscErrorCode DMSwarmProjectField_ApproxP1_PLEX_2D(DM swarm,PetscReal *swarm_field,DM dm,Vec v_field)
484 {
485   PetscErrorCode ierr;
486   const PetscReal PLEX_C_EPS = 1.0e-8;
487   Vec v_field_l,denom_l,coor_l,denom;
488   PetscInt k,p,e,npoints;
489   PetscInt *mpfield_cell;
490   PetscReal *mpfield_coor;
491   PetscReal xi_p[2];
492   PetscScalar Ni[3];
493   PetscSection coordSection;
494   PetscScalar *elcoor = NULL;
495 
496   PetscFunctionBegin;
497   ierr = VecZeroEntries(v_field);CHKERRQ(ierr);
498 
499   ierr = DMGetLocalVector(dm,&v_field_l);CHKERRQ(ierr);
500   ierr = DMGetGlobalVector(dm,&denom);CHKERRQ(ierr);
501   ierr = DMGetLocalVector(dm,&denom_l);CHKERRQ(ierr);
502   ierr = VecZeroEntries(v_field_l);CHKERRQ(ierr);
503   ierr = VecZeroEntries(denom);CHKERRQ(ierr);
504   ierr = VecZeroEntries(denom_l);CHKERRQ(ierr);
505 
506   ierr = DMGetCoordinatesLocal(dm,&coor_l);CHKERRQ(ierr);
507   ierr = DMGetCoordinateSection(dm,&coordSection);CHKERRQ(ierr);
508 
509   ierr = DMSwarmGetLocalSize(swarm,&npoints);CHKERRQ(ierr);
510   ierr = DMSwarmGetField(swarm,DMSwarmPICField_coor,NULL,NULL,(void**)&mpfield_coor);CHKERRQ(ierr);
511   ierr = DMSwarmGetField(swarm,DMSwarmPICField_cellid,NULL,NULL,(void**)&mpfield_cell);CHKERRQ(ierr);
512 
513   for (p=0; p<npoints; p++) {
514     PetscReal   *coor_p,dJ;
515     PetscScalar elfield[3];
516     PetscBool   point_located;
517 
518     e       = mpfield_cell[p];
519     coor_p  = &mpfield_coor[2*p];
520 
521     ierr = DMPlexVecGetClosure(dm,coordSection,coor_l,e,NULL,&elcoor);CHKERRQ(ierr);
522 
523 /*
524     while (!point_located && (failed_counter < 25)) {
525       ierr = PointInTriangle(point, coords[0], coords[1], coords[2], &point_located);CHKERRQ(ierr);
526       point.x = coor_p[0];
527       point.y = coor_p[1];
528       point.x += 1.0e-10 * (2.0 * rand()/((double)RAND_MAX)-1.0);
529       point.y += 1.0e-10 * (2.0 * rand()/((double)RAND_MAX)-1.0);
530       failed_counter++;
531     }
532 
533     if (!point_located){
534         PetscPrintf(PETSC_COMM_SELF,"Failed to locate point (%1.8e,%1.8e) in local mesh (cell %D) with triangle coords (%1.8e,%1.8e) : (%1.8e,%1.8e) : (%1.8e,%1.8e) in %D iterations\n",point.x,point.y,e,coords[0].x,coords[0].y,coords[1].x,coords[1].y,coords[2].x,coords[2].y,failed_counter);
535     }
536 
537     if (!point_located) SETERRQ3(PETSC_COMM_SELF,PETSC_ERR_SUP,"Failed to locate point (%1.8e,%1.8e) in local mesh (cell %D)\n",point.x,point.y,e);
538     else {
539       ierr = _ComputeLocalCoordinateAffine2d(coor_p,elcoor,xi_p,&dJ);CHKERRQ(ierr);
540       xi_p[0] = 0.5*(xi_p[0] + 1.0);
541       xi_p[1] = 0.5*(xi_p[1] + 1.0);
542 
543       PetscPrintf(PETSC_COMM_SELF,"[p=%D] x(%+1.4e,%+1.4e) -> mapped to element %D xi(%+1.4e,%+1.4e)\n",p,point.x,point.y,e,xi_p[0],xi_p[1]);
544 
545     }
546 */
547 
548     ierr = ComputeLocalCoordinateAffine2d(coor_p,elcoor,xi_p,&dJ);CHKERRQ(ierr);
549     /*
550     PetscPrintf(PETSC_COMM_SELF,"[p=%D] x(%+1.4e,%+1.4e) -> mapped to element %D xi(%+1.4e,%+1.4e)\n",p,point.x,point.y,e,xi_p[0],xi_p[1]);
551     */
552     /*
553      point_located = PETSC_TRUE;
554     if (xi_p[0] < 0.0) {
555       if (xi_p[0] > -PLEX_C_EPS) {
556         xi_p[0] = 0.0;
557       } else {
558         point_located = PETSC_FALSE;
559       }
560     }
561     if (xi_p[1] < 0.0) {
562       if (xi_p[1] > -PLEX_C_EPS) {
563         xi_p[1] = 0.0;
564       } else {
565         point_located = PETSC_FALSE;
566       }
567     }
568     if (xi_p[1] > (1.0-xi_p[0])) {
569       if ((xi_p[1] - 1.0 + xi_p[0]) < PLEX_C_EPS) {
570         xi_p[1] = 1.0 - xi_p[0];
571       } else {
572         point_located = PETSC_FALSE;
573       }
574     }
575     if (!point_located){
576       PetscPrintf(PETSC_COMM_SELF,"[Error] xi,eta = %+1.8e, %+1.8e\n",xi_p[0],xi_p[1]);
577       PetscPrintf(PETSC_COMM_SELF,"[Error] Failed to locate point (%1.8e,%1.8e) in local mesh (cell %D) with triangle coords (%1.8e,%1.8e) : (%1.8e,%1.8e) : (%1.8e,%1.8e)\n",coor_p[0],coor_p[1],e,elcoor[0],elcoor[1],elcoor[2],elcoor[3],elcoor[4],elcoor[5]);
578     }
579     if (!point_located) SETERRQ3(PETSC_COMM_SELF,PETSC_ERR_SUP,"Failed to locate point (%1.8e,%1.8e) in local mesh (cell %D)\n",coor_p[0],coor_p[1],e);
580     */
581 
582     Ni[0] = 1.0 - xi_p[0] - xi_p[1];
583     Ni[1] = xi_p[0];
584     Ni[2] = xi_p[1];
585 
586     point_located = PETSC_TRUE;
587     for (k=0; k<3; k++) {
588       if (PetscRealPart(Ni[k]) < -PLEX_C_EPS) point_located = PETSC_FALSE;
589       if (PetscRealPart(Ni[k]) > (1.0+PLEX_C_EPS)) point_located = PETSC_FALSE;
590     }
591     if (!point_located){
592       PetscPrintf(PETSC_COMM_SELF,"[Error] xi,eta = %+1.8e, %+1.8e\n",(double)xi_p[0],(double)xi_p[1]);
593       PetscPrintf(PETSC_COMM_SELF,"[Error] Failed to locate point (%1.8e,%1.8e) in local mesh (cell %D) with triangle coords (%1.8e,%1.8e) : (%1.8e,%1.8e) : (%1.8e,%1.8e)\n",(double)coor_p[0],(double)coor_p[1],e,(double)PetscRealPart(elcoor[0]),(double)PetscRealPart(elcoor[1]),(double)PetscRealPart(elcoor[2]),(double)PetscRealPart(elcoor[3]),(double)PetscRealPart(elcoor[4]),(double)PetscRealPart(elcoor[5]));
594     }
595     if (!point_located) SETERRQ3(PETSC_COMM_SELF,PETSC_ERR_SUP,"Failed to locate point (%1.8e,%1.8e) in local mesh (cell %D)\n",(double)coor_p[0],(double)coor_p[1],e);
596 
597     for (k=0; k<3; k++) {
598       Ni[k] = Ni[k] * dJ;
599       elfield[k] = Ni[k] * swarm_field[p];
600     }
601 
602     ierr = DMPlexVecRestoreClosure(dm,coordSection,coor_l,e,NULL,&elcoor);CHKERRQ(ierr);
603 
604     ierr = DMPlexVecSetClosure(dm, NULL,v_field_l, e, elfield, ADD_VALUES);CHKERRQ(ierr);
605     ierr = DMPlexVecSetClosure(dm, NULL,denom_l, e, Ni, ADD_VALUES);CHKERRQ(ierr);
606   }
607 
608   ierr = DMSwarmRestoreField(swarm,DMSwarmPICField_cellid,NULL,NULL,(void**)&mpfield_cell);CHKERRQ(ierr);
609   ierr = DMSwarmRestoreField(swarm,DMSwarmPICField_coor,NULL,NULL,(void**)&mpfield_coor);CHKERRQ(ierr);
610 
611   ierr = DMLocalToGlobalBegin(dm,v_field_l,ADD_VALUES,v_field);CHKERRQ(ierr);
612   ierr = DMLocalToGlobalEnd(dm,v_field_l,ADD_VALUES,v_field);CHKERRQ(ierr);
613   ierr = DMLocalToGlobalBegin(dm,denom_l,ADD_VALUES,denom);CHKERRQ(ierr);
614   ierr = DMLocalToGlobalEnd(dm,denom_l,ADD_VALUES,denom);CHKERRQ(ierr);
615 
616   ierr = VecPointwiseDivide(v_field,v_field,denom);CHKERRQ(ierr);
617 
618   ierr = DMRestoreLocalVector(dm,&v_field_l);CHKERRQ(ierr);
619   ierr = DMRestoreLocalVector(dm,&denom_l);CHKERRQ(ierr);
620   ierr = DMRestoreGlobalVector(dm,&denom);CHKERRQ(ierr);
621 
622   PetscFunctionReturn(0);
623 }
624 
625 PetscErrorCode private_DMSwarmProjectFields_PLEX(DM swarm,DM celldm,PetscInt project_type,PetscInt nfields,DataField dfield[],Vec vecs[])
626 {
627   PetscErrorCode ierr;
628   PetscInt f,dim;
629 
630   PetscFunctionBegin;
631   ierr = DMGetDimension(swarm,&dim);CHKERRQ(ierr);
632   switch (dim) {
633     case 2:
634       for (f=0; f<nfields; f++) {
635         PetscReal *swarm_field;
636 
637         ierr = DataFieldGetEntries(dfield[f],(void**)&swarm_field);CHKERRQ(ierr);
638         ierr = DMSwarmProjectField_ApproxP1_PLEX_2D(swarm,swarm_field,celldm,vecs[f]);CHKERRQ(ierr);
639       }
640       break;
641     case 3:
642       SETERRQ(PetscObjectComm((PetscObject)swarm),PETSC_ERR_SUP,"No support for 3D");
643       break;
644     default:
645       break;
646   }
647 
648   PetscFunctionReturn(0);
649 }
650 
651 PetscErrorCode private_DMSwarmSetPointCoordinatesCellwise_PLEX(DM dm,DM dmc,PetscInt npoints,PetscReal xi[])
652 {
653   PetscBool is_simplex,is_tensorcell;
654   PetscErrorCode ierr;
655   PetscInt dim,nfaces,ps,pe,p,d,nbasis,pcnt,e,k,nel;
656   PetscFE fe;
657   PetscQuadrature quadrature;
658   PetscReal *B,*xiq;
659   Vec coorlocal;
660   PetscSection coordSection;
661   PetscScalar *elcoor = NULL;
662   PetscReal *swarm_coor;
663   PetscInt *swarm_cellid;
664 
665   PetscFunctionBegin;
666   ierr = DMGetDimension(dmc,&dim);CHKERRQ(ierr);
667 
668   is_simplex = PETSC_FALSE;
669   is_tensorcell = PETSC_FALSE;
670   ierr = DMPlexGetHeightStratum(dmc,0,&ps,&pe);CHKERRQ(ierr);
671   ierr = DMPlexGetConeSize(dmc, ps, &nfaces);CHKERRQ(ierr);
672 
673   if (nfaces == (dim+1)) { is_simplex = PETSC_TRUE; }
674 
675   switch (dim) {
676     case 2:
677       if (nfaces == 4) { is_tensorcell = PETSC_TRUE; }
678       break;
679     case 3:
680       if (nfaces == 6) { is_tensorcell = PETSC_TRUE; }
681       break;
682     default:
683       SETERRQ(PetscObjectComm((PetscObject)dm),PETSC_ERR_SUP,"Only support for 2D, 3D");
684       break;
685   }
686 
687   /* check points provided fail inside the reference cell */
688   if (is_simplex) {
689     for (p=0; p<npoints; p++) {
690       PetscReal sum;
691       for (d=0; d<dim; d++) {
692         if (xi[dim*p+d] < -1.0) SETERRQ(PetscObjectComm((PetscObject)dm),PETSC_ERR_USER,"Points do not fail inside the simplex domain");
693       }
694       sum = 0.0;
695       for (d=0; d<dim; d++) {
696         sum += xi[dim*p+d];
697       }
698       if (sum > 0.0) SETERRQ(PetscObjectComm((PetscObject)dm),PETSC_ERR_USER,"Points do not fail inside the simplex domain");
699     }
700   } else if (is_tensorcell) {
701     for (p=0; p<npoints; p++) {
702       for (d=0; d<dim; d++) {
703         if (PetscAbsReal(xi[dim*p+d]) > 1.0) SETERRQ(PetscObjectComm((PetscObject)dm),PETSC_ERR_USER,"Points do not fail inside the tensor domain [-1,1]^d");
704       }
705     }
706   } else SETERRQ(PetscObjectComm((PetscObject)dm),PETSC_ERR_SUP,"Only support for d-simplex and d-tensorcell");
707 
708   ierr = PetscQuadratureCreate(PetscObjectComm((PetscObject)dm),&quadrature);CHKERRQ(ierr);
709   ierr = PetscMalloc1(npoints*dim,&xiq);CHKERRQ(ierr);
710   ierr = PetscMemcpy(xiq,xi,npoints*dim*sizeof(PetscReal));CHKERRQ(ierr);
711   ierr = PetscQuadratureSetData(quadrature,dim,1,npoints,(const PetscReal*)xiq,NULL);CHKERRQ(ierr);
712   ierr = private_PetscFECreateDefault_scalar_pk1(dmc, dim, is_simplex, 0, &fe);CHKERRQ(ierr);
713   ierr = PetscFESetQuadrature(fe,quadrature);CHKERRQ(ierr);
714   ierr = PetscFEGetDimension(fe,&nbasis);CHKERRQ(ierr);
715   ierr = PetscFEGetDefaultTabulation(fe, &B, NULL, NULL);CHKERRQ(ierr);
716 
717   /* for each cell, interpolate coordaintes and insert the interpolated points coordinates into swarm */
718   /* 0->cell, 1->edge, 2->vert */
719   ierr = DMPlexGetHeightStratum(dmc,0,&ps,&pe);CHKERRQ(ierr);
720   nel = pe - ps;
721 
722   ierr = DMSwarmSetLocalSizes(dm,npoints*nel,-1);CHKERRQ(ierr);
723   ierr = DMSwarmGetField(dm,DMSwarmPICField_coor,NULL,NULL,(void**)&swarm_coor);CHKERRQ(ierr);
724   ierr = DMSwarmGetField(dm,DMSwarmPICField_cellid,NULL,NULL,(void**)&swarm_cellid);CHKERRQ(ierr);
725 
726   ierr = DMGetCoordinatesLocal(dmc,&coorlocal);CHKERRQ(ierr);
727   ierr = DMGetCoordinateSection(dmc,&coordSection);CHKERRQ(ierr);
728 
729   pcnt = 0;
730   for (e=0; e<nel; e++) {
731     ierr = DMPlexVecGetClosure(dmc,coordSection,coorlocal,ps+e,NULL,&elcoor);CHKERRQ(ierr);
732 
733     for (p=0; p<npoints; p++) {
734       for (d=0; d<dim; d++) {
735         swarm_coor[dim*pcnt+d] = 0.0;
736         for (k=0; k<nbasis; k++) {
737           swarm_coor[dim*pcnt+d] += B[p*nbasis + k] * PetscRealPart(elcoor[dim*k+d]);
738         }
739       }
740       swarm_cellid[pcnt] = e;
741       pcnt++;
742     }
743     ierr = DMPlexVecRestoreClosure(dmc,coordSection,coorlocal,ps+e,NULL,&elcoor);CHKERRQ(ierr);
744   }
745   ierr = DMSwarmRestoreField(dm,DMSwarmPICField_cellid,NULL,NULL,(void**)&swarm_cellid);CHKERRQ(ierr);
746   ierr = DMSwarmRestoreField(dm,DMSwarmPICField_coor,NULL,NULL,(void**)&swarm_coor);CHKERRQ(ierr);
747 
748   ierr = PetscQuadratureDestroy(&quadrature);CHKERRQ(ierr);
749   ierr = PetscFEDestroy(&fe);CHKERRQ(ierr);
750 
751   PetscFunctionReturn(0);
752 }
753