## 3.2. What are the different options for ?

The "Ideal Distance" and "Y-ideal Distance"
fields rule distances between nodes. In the tree-parts of the
graph, "Ideal Distance" and "Y-ideal
Distance" are respectively the horizontal and vertical
distances between nodes. In the "loop-parts" of the
graph, the energy algorithm tries to ensure a uniform distance
equal to "Ideal Distance" between two linked nodes.

The field "Max Nb of Steps" allows you to set the
maximum number of steps for the energy algorithm. One step
corresponds to the modification of the position of one node.
When setting the maximal number of steps you should remember
that each node needs to be placed, and its position optimized,
and that this is all the more costly that the structure of the
loop is complex (high number of nodes / edges). If the number of
steps specified is less than the number of nodes to place, the
"Fast" option will be used instead.

The Fast option disables the use of the energy algorithm for
drawing the loops when ticked. The nodes belonging to a loop are
then uniformly placed on a circle, in an attempt to form a
regular polygon. This option significantly speeds-up the
algorithm. There are several cases in which you may want to
choose this option :

if you know that the loops in your graph are indeed forming
regular polygons ;

if you know that the loops in your graph are
"small" (then this is likely to yield satisfactory
results) ;

if you want to draw a large graph, and do not care for an
optimal drawing of each loop.

The "Start Again" option allows you to restart the
drawing algorithm from scratch without having to reset your
model.