Adjusts the columns of nodes within the unfixedLayer to reduce the number of "bends" between the unfixedLayer and its adjacent layers. The direction argument indicates which of the adjacent layers should be taken into consideration when reducing the number of bends. The "weighted bend" between a node U and a node V connected by link L is calculated by abs((U.column + L.portFromColOffset) - (V.column + L.portToColOffset)) * LinkStraightenWeight(L) The LinkStraightenWeight attempts to give higher priority to links between "artificial" nodes; i.e., long links in the final layout will be straighter. The idea is shift nodes to the left and to the right to reduce the bends ensuring that no two nodes have overlapping "allocations" of columns. Return true if some change was made to the layer.

protected virtual bool ShiftBendStraighten( 
   int unfixedLayer,
   int direction
)