possibleRotations = function( coordinate ) {
            var orders = [ "xyz", "xzy", "yxz", "yzx", "zxy", "zyx" ];
            var rotations = [ ];

            for ( var i = 0; i < orders.length; ++i ) {
                rotations.push(
                    coordinateToOrderedRotation( coordinate, orders[ i ] )
                );
            }

            return rotations;
        }
Returns the possible rotations from unit coordinate
to specified coordinate.