Comment by protomyth
14 years ago
Quartz was written new for OS X and didn't use any of the code from Display Postscript. The licensing fee for DPS was cost prohibitive for Apple and NeXT/Apple did not own the code. I am well aware of the PDF and PS specs (I have programmed in PS for a while). It should be noted that PS and PDF have diverged and PS looks to be no longer updating.
I think you discount the complexity of Carbon a little bit.
NeXTStep's IOKit uses Objective-C and the OSX uses a cut spec version of C++. Driver code is not compatible.
I've never really done a whole lot of lower level programming but IIRC 68K/PowerPC was big endian and I believe that a lot of Carbon was pretty stubborn about that.
Also I don't know how much Altivec code would have needed to be ported to SSE (if any).