/* Function seg_cmp returns
* -1 if S1 HAS TO BE to the right/below S2 to avoid a crossing,
* 0 if a crossing is unavoidable or there is no crossing at all or
* the segments are parallel,
* 1 if S1 HAS TO BE to the left/above S2 to avoid a crossing
*
* Note: This definition means horizontal segments have track numbers
* increasing as y decreases, while vertical segments have track numbers
* increasing as x increases. It would be good to make this consistent,
* with horizontal track numbers increasing with y. This can be done by
* switching B_DOWN and B_UP in the first call to segCmp. At present,
* though, I'm not sure what assumptions are made in handling parallel
* segments, so we leave the code alone for the time being.
*/
static int
seg_cmp(segment* S1, segment* S2)
{
if(S1->isVert!=S2->isVert||S1->comm_coord!=S2->comm_coord) {
agerr (AGERR, "incomparable segments !! -- Aborting\n");
longjmp(jbuf, 1);
}
if(S1->isVert)
return segCmp (S1, S2, B_RIGHT, B_LEFT);
else
return segCmp (S1, S2, B_DOWN, B_UP);
}
/* Function seg_cmp returns
* -1 if S1 HAS TO BE to the right/below S2 to avoid a crossing,
* 0 if a crossing is unavoidable or there is no crossing at all or
* the segments are parallel,
* 1 if S1 HAS TO BE to the left/above S2 to avoid a crossing
*
* Note: This definition means horizontal segments have track numbers
* increasing as y decreases, while vertical segments have track numbers
* increasing as x increases. It would be good to make this consistent,
* with horizontal track numbers increasing with y. This can be done by
* switching B_DOWN and B_UP in the first call to segCmp. At present,
* though, I'm not sure what assumptions are made in handling parallel
* segments, so we leave the code alone for the time being.
*/
static int
seg_cmp(segment* S1, segment* S2)
{
if(S1->isVert!=S2->isVert||S1->comm_coord!=S2->comm_coord) {
fprintf (stderr, "incomparable segments !! -- Aborting\n");
exit(1);
}
if(S1->isVert)
return segCmp (S1, S2, B_RIGHT, B_LEFT);
else
return segCmp (S1, S2, B_DOWN, B_UP);
}