static solid *tetrahedron(jigglystruct *js)
{
solid *s;
vertex *vtx;
vector v;
hedge *h;
face *f;
int i;
vector_init(v, 1, 1, 1);
s = solid_new(v);
vector_init(v, -1, -1, 1);
h = s->faces->start;
vtx = vertex_split(h, v);
vector_init(v, -1, 1, -1);
vtx = vertex_split(vtx->h, v);
h = vtx->h;
f = face_split(s->faces, h, h->prev);
vector_init(v, 1, -1, -1);
vertex_split(f->start, v);
f = s->faces->next->next;
h = f->start;
face_split(f, h, h->next->next);
if(js->color_style == COLOR_STYLE_FLOWERBOX) {
f = s->faces;
for(i=0; i<4; i++) {
f->color = flowerbox_colors[i];
f = f->next;
}
}
return s;
}
// vertex_split and helpers
int FEM_Adapt::vertex_split(int n, int n1, int n2)
{
int e1 = theMesh->getElementOnEdge(n, n1);
if (e1 < 0) {
CkPrintf("ERROR: vertex_split: no element with edge [%d,%d]\n", n, n1);
return -1;
}
int e3 = theMesh->getElementOnEdge(n, n2);
if (e3 < 0) {
CkPrintf("ERROR: vertex_split: no element with edge [%d,%d]\n", n, n2);
return -1;
}
return vertex_split(n, n1, n2, e1, e3);
}
/* This will only work with solids composed entirely of
* triangular faces. It first add a vertex to the middle
* of each edge, then walks the faces, connecting the
* dots.
* I'm abusing the fact that new faces and edges are always
* added at the head of the list. If that ever changes,
* this is borked.
*/
static void solid_tesselate(solid *s)
{
edge *e = s->edges;
face *f = s->faces;
while(e) {
vector v;
midpoint(e->left->vtx->v, e->right->vtx->v, v);
vertex_split(e->left, v);
e = e->next;
}
while(f) {
face_tessel2(f);
f=f->next;
}
}