game engine: A group of software routines that render polygonal
models overlaid with texture maps in order to create the illusion of a gaming
world in three dimensions.
gamma correction: The ability to manipulate the gamma--red, green, and blue
(RGB)--values of an image. This can affect how light or dark an image is.
gating item: The limiting item, the slowest moving part that limits the performance
of a system as a whole.
GDI: Graphics Device Interface. A part of the display subsystem
within Windows that controls and maintains how graphics will be displayed
on screen. This usually involves software drivers written for videocards interfacing
with this GDI, and then the data transfers take place.
GDI End-User Interface: The Graphics Developer Interface
is Windows' original graphics API, which lets Windows application developers
draw on-screen. Prior to DirectX, it was the only Windows API for generating
graphics and is the interface used in nearly all nongame Windows applications.
geeky: Used to describe the fickle tastes of individuals
who spend much of their social lives in front of a computer and sprinkle their
conversations with more acronyms than adjectives.
General MIDI: An agreed upon specification by many synthesizer
manufacturers that places the same type of timbres in the same patch location.
For example a piano patch is always in patch 000. There are 128 patches allocated
as well as a reverb and chorus parameter to help fatten the sound.
geometric distortion: A visual flaw in which display content
is bowed or out of proportion, for example, straight lines look curved, squares
look rectangular, and perfect circles look like elongated ellipsoids.
geometry engines: Computer code that accelerates the ability
to manipulate polygons in a 3D model.
geometry transformation: A math-intensive process that
creates the skeleton of a 3D object on a screen. It makes heavy use of floating-point
numbers and matrix multiplication.
GFLOP: A billion floating-point operations per second. FPUs may be compared
in terms of how many GFLOPs they can perform.
giant magneto-resistive: In 1988, scientists in France
and Germany discovered that certain thin-film sandwiches had very large magnetoresistance,
which they termed "giant magnetoresistance." But their structures were laboriously
built and required extremely low temperatures and high magnetic fields. IBM
scientists discovered ways to use standard manufacturing techniques to make
GMR structures that had much greater MR at room temperature and low fields
than the sensors used in MR heads. In 1997, IBM introduced the GMR head, in
which a GMR sandwich replaced the MR element and continued the spectacular
increase in disk drive densities and capacities.
GIF89a: LZW-compressed image format limited to 256 colors.
The 89a spec adds transparency to the animation abilities included in the
87a spec.
Glide: 3Dfx's proprietary programming interface (API) for
its Voodoo family of videocard accelerators. It's usually faster and easier
to program for than Direct3D.
gobos: Patterned mesh or gel placed between a light source
and the scene it illuminates. The resulting patterned lighting effect adds
interest and drama to the scene.
golds: A slang term for the discs created by CD-Recordable
drives. The term gold refers to the 50nm- to 100nm-thick 24K gold layer that
sits atop a thin layer of organic dye on which pits are etched during the
recording process.
gouraud shading: The process of shading 3D polygons to
create realistic environments. Without gouraud shading, the graphics on screen
would resemble chicken wire.
Graffiti: Not what you see all over Los Angeles or New
York. It's a fairly easy-to-use character-recognition application where users
memorize a few specific short-hand commands to enter alphanumeric data.
graphic: An image file. Graphic is another word for "picture."
graphic aperture size: The amount of system memory set aside for use by AGP
video cards.
graphics pipelines: The infrastructure through which graphics
data is passed from the CPU to the AGP/PCI bus through the graphics card and
out to the video screen.
Gremlin: Possibly one of the ugliest vehicles known to
this sector of the galaxy. Was it American or French? No one really knows.
GUI: Graphical user interface. The windows, buttons, menus, scrollbars, and other graphical screen elements that allow a user to control a program. The alternate style is called a CLI (command-line interface)--users type commands at a screen prompt, as in MS-DOS.