DDR (Double
Data Rate):
DDR is a new generation of RAM which doubles on-board
data transfer. DDR RAM allows texture to be loaded
and mapped twice as fast in games.
Depth
shading:
Also
known as distance shading, fog shading
or depth cueing. This is to prevent a processor from having to render
objects in a 3D environment out to infinity, which would cause monumental slowdown.
After a certain predetermined distance, an object is considered to be out of
range and is no longer rendered. To prevent objects suddenly popping up, they
are shaded to appear as though they are coming out of a fog.
Digital:
A
way of representing information (such as the height of a sound wave or the color
of a pixel) that uses a number of discrete values.
Direct3D:
This
is Microsoft DirectX's programming API (Application
Programming Interface) that comes with DirectDraw, DirectSound, DirectPlay,
Direct3D and DirectInput). Direct3D includes support of, and control over, low
level transformations, rasterization and lighting. The latest version of DirectX
8.0 contains Direct3D. There are games made with Direct3D's APIs and these are
100% compatible with 3D Prophet graphics boards.
DirectX:
A series of utilities created by Microsoft, intended to optimize 2D, 3D and
sound features.
Dithering:
A
process which enables the system to create the illusion of displaying more colors
than it can actually generate. Color dithering is achieved by placing dots of
different colors next to each other in a variety of patterns. When looked at
from a distance, the combined effect is a new color, since dithering takes advantage
of the human eye's propensity to average the colors in a small area. For instance,
placing blue and yellow dots next to each other in a checkered pattern will
create an impression of the color green.
DRAM (Dynamic
Random Access Memory):
Conventional random access memory (RAM) used on lower-
and mid-range graphics boards. Random access memory is required by the system
to store data and programs prior to processing. The amount and operating speed
of this memory have a direct incidence on a PC's performance. Indeed, some applications,
such as technical or scientific calculations or CAD (Computer-Assisted Design),
will require a certain minimum amount of memory to operate correctly, offering
decent performance. In addition, the quicker the memory access time, the lower
the processor queuing time.
Draw
in:
This
can occur in 3D games, where whole objects suddenly pop-up into view. It occurs
either because of bad programming of clipping
areas, or a lack of processor power, which prevents the system from rendering
objects until they are too close.
Drop
out:
Occurs
when too many polygons are displayed on-screen
to allow display update at a constant rate. Some
of the polygons may "drop out" and disappear.
DVD
(Digital Versatile Disc):
A
new standard for digital optical discs, DVD is the next step. It promises up
to 26 times the storage capacity of current CD-ROMs.
DVI (Digital
Visual Interface):
The DVI standard for digital display has been established
by the Digital Display Working Group (www.ddwg.org),
an open industry group including Intel, Compaq, Fujitsu, Hewlett Packard, IBM,
NEC and Silicon Image. DVI replaces former standards of digital display to provide
a single standard for digital display. DVI is compatible with older standard
monitors, and requires only a cable adapter to support them. The benefits of
DVI CRTs are: