Help hacking contribution

[zebraplayer]

Hi,

 

I'd like to change the workings of the Order Total v1.2 contribution, but I have no idea how to do this. The contribution is set up to deduct a percentage of the total order amount. I'd like it to deduct a fixed amount, say $1.00, no matter what the total order amount is. How would I go about doing that?

 

I think this is the part of that contribution's code that needs to be altered, but I don't know how to do it.

 

 

function calculate_credit($amount) {

global $order, $customer_id, $payment;

$od_amount=0;

$od_pc = $this->percentage;

$do = false;

if ($amount > $this->minimum) {

$table = split("[,]" , MODULE_PAYMENT_DISC_TYPE);

for ($i = 0; $i < count($table); $i++) {

if ($payment == $table[$i]) $do = true;

}

 

Can anyone help. I have tried changing "percentage" to "amount", but it didn't work.

 

Thanks for your help in advance.

 

-zp