[twopi] Allow user to explicitly specify a rank / distance from the root (enhancement)
Steps to reproduce
twopi currently sets the physical distance of a node from the root based on minimum distance (spanning tree) from the root - unlike dot that sets default rank based on greatest distances.
This enhancement would allow the user to explicitly specify one of two alternatives:
- use longest distance from the root (similar to the dot default) for all nodes
- explicitly specify rank for individual nodes
Expected Behaviour
This enhancement would allow the user to more easily manage the placement of nodes on specific ranks (rings)
Actual Behaviour
The spanning tree algorithm (shortest distance) is quite useful, but sometimes not appropriate for the user's goals.
OS Version
all
Graphviz Version
current
Additional info
Fill in with anything else that might be important.