Line item Calc not available


Using 1.5.3 after working up from last 1.4 upgrades and grappling with customizing the invoice especially presentation of calculations.

The current basic invoice template will list line items and subtotals to include: Qty, Unit price, Discount, then total inc VAT without showing the net subtotal or indicating the tax is included. This means the line looks like:

Which looks confusing to my eye.

I could edit the /modules.invoices/models/Mdl_item_amounts.php and change the total calc to exclude tax but that would always be overwritten during upgrades.

The better solution might be to have a item_netsubtotal variable which could be useful in many areas but again will disappear each upgrade. OR even a template and add a line to head the vat element to the line item listings but this makes the invoice very compressed and again less clear.

Looks like the invoice creation/edit does calculate the net but it isnt available in the invoice PDF template.

What is the most persistent and recommended approach to solve this?



Just to add Item subtotal is not enough as it doesnt account for discounts - $item_subtotal = $item->item_quantity * $item->item_price;