/*
* attach and install edges between clusters.
* essentially, class2() for interclust edges.
*/
void interclexp(graph_t* subg)
{
graph_t *g;
node_t *n;
edge_t *e,*prev;
g = subg->root;
for (n = agfstnode(subg); n; n = agnxtnode(subg,n)) {
/* N.B. n may be in a sub-cluster of subg */
prev = NULL;
for (e = agfstedge(subg->root,n); e; e = agnxtedge(subg->root,e,n)) {
if (agcontains(subg,e)) continue;
/* short/flat multi edges */
if (mergeable(prev,e)) {
if (e->tail->u.rank == e->head->u.rank) e->u.to_virt = prev;
else e->u.to_virt = NULL;
if (prev->u.to_virt == NULL) continue; /* internal edge */
merge_chain(subg,e,prev->u.to_virt,FALSE);
safe_other_edge(e);
continue;
}
/* flat edges */
if (e->tail->u.rank == e->head->u.rank) {
if (find_flat_edge(e->tail,e->head) == NULL) {
flat_edge(g,e); prev = e;
}
else prev = NULL;
continue;
}
assert (e->u.to_virt != NULL);
/* forward edges */
if (e->head->u.rank > e->tail->u.rank) {
make_interclust_chain(g,e->tail,e->head,e);
prev = e;
continue;
}
/* backward edges */
else {
/*
I think that make_interclust_chain should create call other_edge(e) anyway
if (agcontains(subg,e->tail)
&& agfindedge(subg->root,e->head,e->tail)) other_edge(e);
*/
make_interclust_chain(g,e->head,e->tail,e);
prev = e;
}
}
}
}
/*
* attach and install edges between clusters.
* essentially, class2() for interclust edges.
*/
void interclexp(graph_t * subg)
{
graph_t *g;
node_t *n;
edge_t *e, *prev, *next;
g = agroot(subg);
for (n = agfstnode(subg); n; n = agnxtnode(subg, n)) {
/* N.B. n may be in a sub-cluster of subg */
prev = NULL;
for (e = agfstedge(agroot(subg), n); e; e = next) {
next = agnxtedge(agroot(subg), e, n);
if (agcontains(subg, e))
continue;
#ifdef WITH_CGRAPH
/* canonicalize edge */
e = AGMKOUT(e);
#endif
/* short/flat multi edges */
if (mergeable(prev, e)) {
if (ND_rank(agtail(e)) == ND_rank(aghead(e)))
ED_to_virt(e) = prev;
else
ED_to_virt(e) = NULL;
if (ED_to_virt(prev) == NULL)
continue; /* internal edge */
merge_chain(subg, e, ED_to_virt(prev), FALSE);
safe_other_edge(e);
continue;
}
/* flat edges */
if (ND_rank(agtail(e)) == ND_rank(aghead(e))) {
edge_t* fe;
if ((fe = find_flat_edge(agtail(e), aghead(e))) == NULL) {
flat_edge(g, e);
prev = e;
} else if (e != fe) {
safe_other_edge(e);
if (!ED_to_virt(e)) merge_oneway(e, fe);
}
continue;
}
/* This assertion is still valid if the new ranking is not used */
#ifndef WITH_CGRAPH
assert(ED_to_virt(e) != NULL);
#endif
/* forward edges */
if (ND_rank(aghead(e)) > ND_rank(agtail(e))) {
make_interclust_chain(g, agtail(e), aghead(e), e);
prev = e;
continue;
}
/* backward edges */
else {
/*
I think that make_interclust_chain should create call other_edge(e) anyway
if (agcontains(subg,agtail(e))
&& agfindedge(subg->root,aghead(e),agtail(e))) other_edge(e);
*/
make_interclust_chain(g, aghead(e), agtail(e), e);
prev = e;
}
}
}
}