I am trying to make a clustered column chart in Vega where in if the values in the category are positive and negative, they are going to be stacked in one column but if the values in the category are both positive or both negatives then they must be displayed side by side instead of stacked.

However, the column positioning is not always centered as setting a definite offset does not work and will change depending on the number of columns. Does anyone know how I get this to be dynamic.. might need a computation in the column width

current implementation