Fix bug in splines=line case. When polylines are used to handle edges

between adjacent ranks, replace by line segments.

diff --git a/lib/dotgen/dotsplines.c b/lib/dotgen/dotsplines.c
index 1fd64bb644bc01f470b619530d157a1bba0cbe94..04609bef39ee698c7c69b27acc8d8642f54d3c51 100644 (file)
--- a/lib/dotgen/dotsplines.c
+++ b/lib/dotgen/dotsplines.c
@@ -1254,6 +1254,8 @@ leftOf (point p1, point p2, point p3)
  *
  * If the endpoints are on adjacent ranks, revert to usual code by
  * returning 0.
+ * This is done because the usual code handles the interaction of
+ * multiple edges better.
  */
 static int 
 makeLineEdge(edge_t* fe, point* points, node_t** hp)
@@ -1413,7 +1415,14 @@ make_regular_edge(spline_info_t* sp, path * P, edge_t ** edges, int ind, int cnt
            P->end.theta = PI / 2, P->end.constrained = TRUE;
            completeregularpath(P, segfirst, e, &tend, &hend, boxes, boxn, 1);
            if (splines) ps = routesplines(P, &pn);
-           else ps = routepolylines (P, &pn);
+           else {
+               ps = routepolylines (P, &pn);
+               if ((et == ET_LINE) && (pn > 4)) {
+                   ps[1] = ps[0];
+                   ps[3] = ps[2] = ps[pn-1];
+                   pn = 4;
+               }
+           }
            if (pn == 0)
                return;
            for (i = 0; i < pn; i++)
@@ -1447,6 +1456,15 @@ make_regular_edge(spline_info_t* sp, path * P, edge_t ** edges, int ind, int cnt
                        longedge);
        if (splines) ps = routesplines(P, &pn);
        else ps = routepolylines (P, &pn);
+       if ((et == ET_LINE) && (pn > 4)) {
+           /* Here we have used the polyline case to handle
+            * an edge between two nodes on adjacent ranks. If the
+            * results really is a polyline, straighten it.
+            */
+           ps[1] = ps[0];
+           ps[3] = ps[2] = ps[pn-1];
+           pn = 4;
+        }
        if (pn == 0)
            return;
        for (i = 0; i < pn; i++)