MVertex_ptr ME_Split_SimplexMesh(MEdge_ptr esplit, double *splitxyz) {
int i, j, k, rfdir, ntets=0, ntris=0, *fdim, *fid, *rid=NULL, found;
MVertex_ptr vsplit, ev[2], (*tetverts)[4]=NULL, (*triverts)[3]=NULL, fv;
MVertex_ptr fvarr[3], rvarr[4];
MFace_ptr f;
MRegion_ptr r;
List_ptr etets, rfaces, etris, fverts;
Mesh_ptr mesh = ME_Mesh(esplit);
ev[0] = ME_Vertex(esplit,0);
ev[1] = ME_Vertex(esplit,1);
etets = ME_Regions(esplit);
if (etets) {
ntets = List_Num_Entries(etets);
tetverts = (MVertex_ptr (*)[4]) malloc(ntets*sizeof(MVertex_ptr [4]));
rid = (int *) malloc(ntets*sizeof(int));
}
for (i = 0; i < ntets; i++) {
r = List_Entry(etets,i);
rfaces = MR_Faces(r);
/* Find a tet face that uses ev[0] but not ev[1] */
found = 0;
for (j = 0; !found && j < 4; j++) {
f = List_Entry(rfaces,j);
fverts = MF_Vertices(f,1,0);
if (List_Contains(fverts,ev[0]) &&
!List_Contains(fverts,ev[1])) {
found = 1;
/* Get the two vertices (a,b) of this face excluding ev[0] in
such an order that ev[0],a,b,ev[1] will form a valid
tet. This requires checking whether the face points into or
out of this tet (look at rfdir) */
rfdir = MR_FaceDir_i(r,j);
for (k = 0; k < 3; k++) {
fv = List_Entry(fverts,k);
if (fv == ev[0]) {
tetverts[i][0] = ev[0];
tetverts[i][1] = rfdir ? List_Entry(fverts,(k+2)%3) : List_Entry(fverts,(k+1)%3);
tetverts[i][2] = rfdir ? List_Entry(fverts,(k+1)%3) : List_Entry(fverts,(k+2)%3);
tetverts[i][3] = ev[1];
}
}
}
List_Delete(fverts);
if (found) break;
}
List_Delete(rfaces);
}
/* Now that we finished collecting info about the connected tets we
can delete them */
if (etets) {
for (i = 0; i < ntets; i++)
MR_Delete(List_Entry(etets,i),0);
List_Delete(etets);
}
/* Now get the triangular face connected to the edge. For each
triangular face, record the vertex opposite to edge esplit and
delete the triangular face */
etris = ME_Faces(esplit);
if (etris) {
ntris = List_Num_Entries(etris);
triverts = (MVertex_ptr (*)[3]) malloc(ntris*sizeof(MVertex_ptr[3]));
fdim = (int *) malloc(ntris*sizeof(int));
fid = (int *) malloc(ntris*sizeof(int));
}
for (i = 0; i < ntris; i++) {
f = List_Entry(etris,i);
fverts = MF_Vertices(f,1,0);
for (j = 0; j < 3; j++) {
fv = List_Entry(fverts,j);
if (fv != ev[0] && fv != ev[1]) {
triverts[i][0] = fv;
triverts[i][1] = List_Entry(fverts,(j+1)%3);
triverts[i][2] = List_Entry(fverts,(j+2)%3);
fdim[i] = MF_GEntDim(f);
fid[i] = MF_GEntID(f);
break;
}
}
List_Delete(fverts);
MF_Delete(f,0);
}
if (etris) List_Delete(etris);
/* Now split the edge itself */
vsplit = ME_Split(esplit, splitxyz);
/* Now for each tri face that we deleted, create two tri faces that
incorporate the split vertex, one of the split edge vertices and
opposite vertex */
for (i = 0; i < ntris; i++) {
/* First triangle */
fvarr[0] = triverts[i][0];
fvarr[1] = triverts[i][1];
fvarr[2] = vsplit;
f = MF_New(mesh);
MF_Set_Vertices(f,3,fvarr);
MF_Set_GEntDim(f,fdim[i]);
MF_Set_GEntID(f,fid[i]);
/* Second triangle */
fvarr[0] = triverts[i][0];
fvarr[1] = vsplit;
fvarr[2] = triverts[i][2];
f = MF_New(mesh);
MF_Set_Vertices(f,3,fvarr);
MF_Set_GEntDim(f,fdim[i]);
MF_Set_GEntID(f,fid[i]);
}
if (ntris) {
free(triverts);
free(fdim);
free(fid);
}
/* Now for each tet that we deleted, create two tets (these will use
the split faces that are already created */
for (i = 0; i < ntets; i++) {
rvarr[0] = vsplit;
rvarr[1] = tetverts[i][2];
rvarr[2] = tetverts[i][1];
rvarr[3] = tetverts[i][0];
r = MR_New(mesh);
MR_Set_Vertices(r,4,rvarr,0,NULL);
MR_Set_GEntID(r,rid[i]);
rvarr[0] = vsplit;
rvarr[1] = tetverts[i][1];
rvarr[2] = tetverts[i][2];
rvarr[3] = tetverts[i][3];
r = MR_New(mesh);
MR_Set_Vertices(r,4,rvarr,0,NULL);
MR_Set_GEntID(r,rid[i]);
}
if (ntets) {
free(tetverts);
free(rid);
}
return vsplit;
}
MVertex_ptr MF_Split_SimplexMesh(MFace_ptr fsplit, double *splitxyz) {
int i, j, k, rfdir=1, ntets=0, ntris=0, *rid=NULL, fgdim, fgid, found;
MVertex_ptr vsplit, ev[2], (*tetverts)[4]=NULL, triverts[3], fv;
MVertex_ptr fvarr[3], rvarr[4];
MFace_ptr f;
MRegion_ptr r;
List_ptr fedges, ftets, rfaces, fverts;
Mesh_ptr mesh = MF_Mesh(fsplit);
/* point is not on the boundary of the face */
ftets = MF_Regions(fsplit);
if (ftets) {
ntets = List_Num_Entries(ftets);
tetverts = (MVertex_ptr (*)[4]) malloc(ntets*sizeof(MVertex_ptr [4]));
rid = (int *) malloc(ntets*sizeof(int));
}
for (i = 0; i < ntets; i++) {
r = List_Entry(ftets,i);
rfaces = MR_Faces(r);
/* Find the face to be split and get the first three vertices
in a suitable order from it. Also, find another face and
get a vertex that is not in the face to be split. This vertex
forms the fourth vertex of the tet */
for (j = 0; j < 4; j++) {
f = List_Entry(rfaces,j);
if (f == fsplit) {
rfdir = MR_FaceDir_i(r,j);
fverts = MF_Vertices(f,!rfdir,0);
for (k = 0; k < 3; k++) {
tetverts[i][0] = List_Entry(fverts,0);
tetverts[i][1] = List_Entry(fverts,1);
tetverts[i][2] = List_Entry(fverts,2);
}
List_Delete(fverts);
break;
}
}
found = 0;
for (j = 0; j < 4; j++) {
f = List_Entry(rfaces,j);
if (f != fsplit) {
fverts = MF_Vertices(f,!rfdir,0);
for (k = 0; k < 3; k++) {
fv = List_Entry(fverts,k);
if (!MF_UsesEntity(fsplit,fv,MVERTEX)) {
tetverts[i][3] = fv;
found = 1;
break;
}
}
List_Delete(fverts);
}
if (found) break;
}
List_Delete(rfaces);
}
/* Now that we finished collecting info about the connected tets we
can delete them */
if (ftets) {
for (i = 0; i < ntets; i++)
MR_Delete(List_Entry(ftets,i),0);
List_Delete(ftets);
}
/* Delete the face itself */
fverts = MF_Vertices(fsplit,1,0);
for (i = 0; i < 3; i++)
triverts[i] = List_Entry(fverts,i);
List_Delete(fverts);
fgdim = MF_GEntDim(fsplit);
fgid = MF_GEntID(fsplit);
/* Split the face */
vsplit = MF_Split(fsplit, splitxyz);
/* Create three tets for each tet that was deleted */
for (i = 0; i < ntets; i++) {
for (j = 0; j < 3; j++) {
r = MR_New(mesh);
rvarr[0] = vsplit;
rvarr[1] = tetverts[i][j];
rvarr[2] = tetverts[i][(j+1)%3];
rvarr[3] = tetverts[i][3];
MR_Set_Vertices(r, 4, rvarr, 0, NULL);
MR_Set_GEntID(r,rid[i]);
}
}
if (ntets) {
free(tetverts);
free(rid);
}
return vsplit;
}