Add item to totals in pdf invoice

Question

We have a pdf invoices with totals displaying both prices with included and excluded tax, but without a subtotal. What we need now only on pdf invoices is to display a total when the discount (coupon code) is active. I see that this works, but not on the totals itself:

$subtotal = $item->getRowTotal() + $item->getTaxAmount() + $item->getHiddenTaxAmount()
        - $item->getDiscountAmount();  

What would be the proper way of showing this total line on PDF invoices?

Answer 1

Maybe I am wrong but I thought the orders Grand Total would include the discount also so that something like the following would give you how much the user has paid:

$order->getGrandTotal()

If this does not work you can combine the subtotal, shipping amount and then remove the discount:

$order->getSubtotal() + $order->getShippingAmount() + $order->getDiscountAmount()

Note that on orders the discount are normally stored as a negative amount