[Dot] Weird edges within same node rank with rank=same option

[GadgetSteve]

Ported Issue from Mantis
Original ID: 1164
Reported By: J. Barnholt

SEVERITY: MINOR
Submitted: 2006-08-03 10:16:59

OS: --

VERSION: 2.9 (31/07/06)

DESCRIPTION

The attached input file causes weird edges between the nodes of the lowest rank.
Removing the "rank=same" results in correct placement of the edges.

In an earlier version of GraphViz this worked fine (sorry, don't have this release any more - must have been 2.6 or 2.7 I guess)

This edge rendering quirk makes the result badly readable.

STEPS TO REPRODUCE

digraph KSAM_Segment_1038 {
  node [shape=record fontname="Courier" fontsize=9.0];
{
rank=same
9 [label = "{ Master: '' |  {  <P> A: : 4 | <S> B:  1588 }\
| { #1 | '' | <SI1> X1 }\
| { #2 | '00000004000004190000082A' | <SI2> X2 }\
| { #3 | '000000040000041900000848' | <SI3> X3 }\
| { #4 | '000000040000041900003812' | <SI4> X4 } }" ];
}

 9:SI1:e -> 5 [headport=n arrowsize=0.75];
 9:SI2:e -> 25 [headport=n arrowsize=0.75];
 9:SI3:e -> 10 [headport=n arrowsize=0.75];
 9:SI4:e -> 27 [headport=n arrowsize=0.75];


{
rank=same
5 [label = "{  Master: '00000004 00000419 0000082A' |  {  <P> A: : 0 | <S> B:  1824 } }" ];
 5:S -> 25:P   [fontname="Courier" fontsize=10.0 arrowsize=0.75 label="S"];
25 [label = "{Master: '00000004 00000419 00000848' |  {  <P> A: : 0 | <S> B:  896 } }" ];
 25:P -> 5:S   [fontname="Courier" fontsize=10.0 arrowsize=0.75 label="P"];
 25:S -> 10:P   [fontname="Courier" fontsize=10.0 arrowsize=0.75 label="S"];
10 [label = "{ Master: '00000004 00000419 00003812' |  {  <P> A: : 0 | <S> B:  1860 } }" ];
 10:P -> 25:S   [fontname="Courier" fontsize=10.0 arrowsize=0.75 label="P"];
 10:S -> 27:P   [fontname="Courier" fontsize=10.0 arrowsize=0.75 label="S"];
27 [label = "{ Master: '' |  {  <P> A: : 0 | <S> B:  1846 } }" ];
 27:P -> 10:S   [fontname="Courier" fontsize=10.0 arrowsize=0.75 label="P"];
}

}

ADDITIONAL INFORMATION

Great program anyway!
Helps us a lot to debug our various datastructures