QuickDraw GX was a replacement for the QuickDraw (QD) 2D graphics engine and Printing Manager inside the "classic" Mac OS. Its underlying drawing platform was a resolution-independent object oriented retained mode system, making it much easier for programmers to perform common tasks (compared to the original QuickDraw). Additionally, GX added various curve-drawing commands that had been lacking from QD, as well as introducing TrueType as its basic font system.
While GX certainly addressed many of the problems QD had, by the time it was available most developers had already developed their own solutions to these problems anyway. GX also suffered from causing a number of incompatibilities in existing programs, notably those that had developed their own QD extensions. This, coupled with opposition from an important fraction of the developer market, especially PostScript owner Adobe, and a lack of communication from Apple about the benefits of GX and why users should adopt it, led to the technology being sidelined. QuickDraw GX was eventually "killed" with the purchase of NeXT and the eventual adoption of the Quartz imaging model in Mac OS X, but many of its component features lived on and are now standard in the current Macintosh platform.
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