How to replace the subtotal including tax with subtotal excluding tax in the pdf invoice?

Question

My pdf invoice show now the subtotal including tax, the tax, shipping taxes, and the grand total including taxes and i want to show the subtotal excluding tax instead of including tax. I tried to edit the

/app/code/local/Mage/Sales/Model/Order/Pdf/Items/Invoice/Default.php 
/app/code/local/Mage/Sales/Model/Order/Pdf/Invoice.php
/app/code/local/Mage/Sales/Model/Order/Pdf/Total/Default.php

Can anyone point me to the right direction? Thank you

Answer 1

its simple. go to system -> configuration select Tax under Sales tab

In Orders, Invoices, Credit Memos Display Settings you could set whatever you need..

Answer 2

You need to replicate magento behavior regarding taxes but locally. I never needed this into the wild but this is how I'd be doing it.

You can alter the Total\Default.php. Start with getFullTaxInfo:line 88. Play with that global setting (Orders, Invoices, Credit Memos Display Settings) and use var_dump into that function to detect the changes into variable $taxClassAmount. After you built your idea of how data should be sent later on, into the invoice pdf, revert the global setting and start changing the code to show totals as it was when global config was set to excluding tax. Basically you need to recode $taxClassAmount to look like global config was set as excluding tax.

DO NOT alter app/core/core files. Use module rewrites and move additional coding into app/code/local.