This generally comes down to the specific implementation of the payment method. However the default payment methods provide this functionality by first defining a toPdf method - like this
class Mage_Payment_Block_Info_Purchaseorder extends Mage_Payment_Block_Info
{
protected function _construct()
{
parent::_construct();
$this->setTemplate('payment/info/purchaseorder.phtml');
}
public function toPdf()
{
$this->setTemplate('payment/info/pdf/purchaseorder.phtml');
return $this->toHtml();
}
}
Which in this case will reference this template file. Your payment method might not have it's own specified toPdf method in which case you will end up using the default template which will affect all not specified payment methods.
To customise admin templates I would suggest your own admin theme, see here for details. Just copy the relevant file to the your theme and add your information there.
Another avenue to look into is to update the payment method to provide its specific information similar to how the CC method does it
Best Answer
You can add specific text after total price follow the code
First override that block add this code in your config file between
<global/>
:Create file in app/code/local/Namespace/Module/Model/Order/Pdf/Invoice.php and add the below function at the end of the file:
Now, you need to call this insertText() function in the getPdf() function and add this getPdf() function after insertText() function like here:
$this->insertText($page); that call your custom text function so you need to add before $this->_afterGetPdf(); this function.