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flicker-free. The acronym refers to the National Television Systems
Committee, which devised this color video standard in 1953.
Offscreen Memory
An area of memory used to preload images so that they can be quickly
drawn to the screen. Offscreen memory refers to all of the remaining video
memory not taken up by the front buffer, which holds the contents of the
display screen currently visible.
OpenGL®
Short for “Open Graphics Library,” this is an industry standard for cross-
platform 3D graphics development. It consists of a large number of
functions that can be called upon in various programs, such as games,
CAD, and virtual-reality systems, to produce complex 3D objects from
simpler, more “primitive” building blocks. Implementations currently exist
under Windows®, Mac OS® X, and various forms of Unix, including
Linux®.
PAL
An acronym for “Phase Alternating Line”, the name for a video broadcast
standard used in much of Europe (except France), most of Asia, the
Middle-East, Africa and Australia. It draws a total of 625 vertical interlaced
frames of video at a refresh rate of 25 Hz.
Pipeline
In relation to computer graphic processors, refers to the number of separate
arithmetic units available for rendering the output on a display. In general,
more pipelines available on a graphical processor means there are more 3D
rendering capabilities available, increasing overall 3D performance.
Pixel
All computer images are made up of tiny dots. Each individual dot is called
a pixel, a word created from the term “picture element.” A pixel is the
smallest indivisible unit of a digital image and can be only a single color.
The size of the pixel depends on how the display resolution has been set.
The smallest size a pixel can be is determined by the display’s dot pitch,
which is measured in millimeters (mm).