A Trapezoid is a Distorted 2 x 2 that can be formed from a normal
2 x 2 after any two adjacent dancers each move
a distance of one matrix position directly away from each other.
From a 2 x 4, there are two Trapezoids. The Ends of one side work with
the Centers of the other side within a Distorted Box.
The traffic pattern for some Trapezoid calls can be horrendous. Use
Stars as necessary and try to get to your ending position without
colliding with any other dancers.
Calls must end on original Trapezoid footprints. Shape-changing
calls are not allowed.
Trapezoid Couple Up
See also Magic Line | Wave CONCEPT [C3B]
which (from Parallel Lines) involves the same footprints, but dancers work within a
Distorted Line instead of a Distorted Box.