[comp.sys.mac] Printer drivers for the Macintosh.

radford@calgary.UUCP (Radford Neal) (04/20/87)

In article <6014@dartvax.UUCP>, earleh@dartvax.UUCP writes:

> Printer drivers for standard
> printers cost from $100 to $400, and are well worth it, considering
> the complexity of the code involved.  Basically, the poor programmer
> has to rewrite QuickDraw, the Macintosh graphics package, for each
> printer supported by the printer driver.  In addition, the information
> needed to do this has been removed from the new editions of Inside
> Macintosh...

Yeah, it's horrible. And what's more, it's COMPLETELY UNNECESSARY!

To support screen dumping, a printer driver currently has to implement a 
capability to print a bit map. Apple could easily write a "generic"
printer driver that uses this driver request to do everything else.
Supporting a new printer would then require about a page of code.

Anyone at Apple listening? Or does Apple make lots of money off of
Imagewriter sales?

     Radford Neal


PS: Actually, things are really complicated. You don't have to rewrite
quickdraw if you just want to print at 72 dots/inch. If you want to
use 144 dots/inch, you sort of have to rewrite quickdraw - you have to
intercept all the calls, scale the parameters, and then re-issue the
modified request. Except that you can't easily scale regions or pictures
without knowing the internal structure...  Bleach.