Virtual channels define possible passing ways for wires. They
do not have to exist physically. You can imagine them as streets
in the town.
To go from Point (A) to point (B) you have to select and follow
the streets. As a default, SpaceCable always selects the ‘shortest
way’ between two points and automatically route the wires from component to
component to build up the harness with the smallest consumption
of wires.
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