As part of this conversion, Apple also ported the graphics engine from the licence-encumbered Display PostScript to the licence-free Quartz (which has been called "Display PDF"). Quartz provided native calls that could be used from either Carbon or Cocoa, as well as offering Java 2D-like interfaces as well. The underlying operating system itself was further isolated and released as Darwin.
As part of this conversion Apple also ported the graphics engine from the licence-encumbered Display PostScript to the licence-free Quartz (which has been called "Display PDF"). Quartz provided native calls that could be used from either Carbon or Cocoa as well as offering Java 2D-like interfaces as well The underlying operating system itself was further isolated and released as Darwin.