Third Generation Display Layers Other than OS X?

jayegirl asks: "The display subsystem in MacOS X seems like a 'really good thing'(tm), and so, I was wondering, what other third generation display layers -- using screen representations based on shapes, rather than pixels -- exist or are under development. Are there any open source projects in this direction?"

Comments

PostScript

[maggard]

PostScript is generally though of as a Page Display Language however it's been applied as a display rendering layer also.

Sun Microsystems' James Gosling created a displayed PostScript as the basis for NeWS around 1985. This implementation was never particularly Adobe/Apple-PostScript compatible and was only licensed from Adobe shortly before Sun abandoned it. However it was the first use of PostScript for a windowing system.

NeXT then licensed & underwrote development of PostScript into Display PostScript (no direct relation to displayed PostScript.) This was the basis for NeXT's NextStep interface and lives on today in GNUstep.

Apple has recently independantly implemented the PostScript-derived PDF from public specifications for it's Quartz rendering layer in it's recently released MacOS X.

Thus you've a single well known, well documented language that's been used for three independant windowing systems over the course of 15 years, two of them independant of the language's licensors. Add that to it's direct application to printing and it's a pretty powerful argument for further consideration as an X-Window alternative/successor.