Creating rounding rules to product sales price that apply globally...

[Genius WebDesign]

Hi,

I want to apply some rounding rules to the final product sales price (product price inkl. all taxes and calculation rules), and they need to apply globally, meaning that the rounding rule must apply to the final product price in the following places; frontend (category view and product details view), shopping cart, order confirmations and invoices.

In product details view I know that this is the code that outputs the value of the final product sales price:

Code Select Expand

$this->product->prices['salesPrice']

My question is, where (in which file) do I apply my rounding rules?