Sum of Item Discount
I have a complex discount calculation in my cart, which is recalculated on-the -fly, depending on the current login.
At present, the discount is shown on a per item basis and displayed as a discount calculation.
instead, i would like to create an additional calculation in my cart.
totalweight is simply [weight] * [qty]
total price is [price] * [qty]
is it possible to calculate totalitemdiscount which is a sum of an existing calculation [itemdiscount] ?