Generic Printer Driver

Hello!

I want to create a printer driver where the users
can print and the printout will be visible on screen
as a preview, or to be able to recognise the content
of a printed text.

This regards two projects that I am involved in. I
tried to understand what I have to do to create the
simplest printer driver which will be device independent.

There are two options as far as I can understand. The first
is to use a spool file viewer (instead of a printer driver) or
to create a printer driver.

Am i asking too much? I just want to find out how to build that driver!

Thank you in advance,

Panayiotis
___