D-Man
(C) MELTED SNOW, 1998
3D-accelerator. How this is done on a PC.
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Accelerator (the accelerator) is a set
Part of the video card or a specially designed card for
performing different operations on work over the image. When
This significantly reduces CPU utilization, resulting in a
significant acceleration is achieved in the work (depending on
accelerator and applications from 20-30% to several tens of
times). Very conditional accelerators can be divided by
targets: accelerator graphics (line drawing, polygon fill
color, etc.) are generally integrated into all modern boards;
Accelerators animation (support MPEG, video scaling, etc.);
three-dimensional graphics accelerator - contains a set of
standard tools not only for acceleration, but also change the
image, taking into account all possibilities of 3D.
The effects that get in the 3D-accelerator:
Alpha-blending - alpha blending. Texture mapping with different
the alpha parameter - the level of transparency. Ability to
correctly reproduce the overlapping textures. Anti-aliasing -
smoothing the contours of objects, eliminating the "Jaggies"
forms. Bi-linear filtering - the two-line filtering. The color
of each pixel is determined by interpolating the four adjacent
colors. Delivers increased image quality textures.
Bus-mastering - control of the bus. Allows the board directly,
without involvement of the central protsesskra access system
memory, saving computer resources. Significantly increases the
speed processing of graphics data. Requires the installation of
the slot, supporting management. CCIR-601 - digital television
standard that specifies the format frame rules for converting a
standard analovogo video (NTSC, PAL, SECAM) to digital signals,
the encoding method tsidrogo video. Color dithering -
compressing palette that will play full-color images in a lower
color depth (8 and 16-bit).
Color key - the color code. Parameter characterizing the change
color pixel, depending on its remoteness.
Contributes to a more realistic image.
DAC (RAMDAC) - (Digital-to-Analog Converter) converter,
forming an analog RGB-signal to the monitor from a digital
representation of pixels. The rate of its work primarily
depends on the frequency of updating computer screen.
Depth cueing - the effect of simulating the depth of the image
by reducing the brightness of more distant elements. Double
buffering - Double buffering. In memory instead of one
identifies two areas in which formed the image frame screen.
Reading the content comes from that part of the buffer where
the frame is fully formed, which increases the smoothness of
playback (especially important for video clips). EDO DRAM -
memory with enhanced access, which has the lowest rate from all
types of memory, but also the cheapest. EDO DRAM installed on
your video card has a higher rate than similar memory for
motherboards. Fogging - aliasing mist to distant osekty.Ne
only makes the image more realistic, but a few offloads
accelerators obobrazhenii 3D-graphics. Frame buffer - a frame
buffer. Memory area, which forms the screen image. Gouraud
ahading - Gouraud shading on. Calculation method, which
provides a smooth change of color of the surface in simulated
light source space. Unlike the flat paint provides a more
realistic image, but poteblyaet more resources. MDRAM -
multibankovaya memory based on technology for chips with
high-bit disk access. For 128-bit access enough only 2Mb of
memory instead of 4Mb for other species. May built up in small
volumes. MIP-mapping - saving multiple texture size to speed
up the imposition of changing the geometric dimensions of the
three-dimensional surface.
Perspective corrected texture mapping-texture mapping with
perspective correction. One of the most important functions for
three-dimensional accelerators. Provides the correct
reproduction of textures at different spatial positions basics
overlay. RGB - the color format of the image signal formed by
the video card to monitor PC. SGRAM - Synchronous Graphics
Memory. The most modern form Memory is relatively cheap, with
the highest rate of access works in contrast to other species
at a frequency of 100 MHz. Videoanalog widely used by SDRAM.
Texture - texture. The image used for drawing on
three-dimensional surface. Tri-linear filtering - the
three-line filtering. The color of each pixel is determined by
interpolating the colors of eight contiguous. Provides the best
image quality of textures. Video scaling - scaling of the
video. Correct reproduction of the video in a window of varying
size. Video texture - visual textures. Use as textures on the
surface of the digitized video. VRAM - (Video-RAM) two-port
(allowing access the data simultaneously video processor and
DAC) video memory. On average, 2 times more expensive than EDO
DRAM, but faster. At the moment supplanted by fast single port
memory SGRAM. WRAM-(Windows-RAM) dual port video RAM, which
has a 50% higher than the VRAM access speed, as well as maps
and the Gulf ki rectangular areas. Used in high-power adapters.
X / Y interpolation - X / Y interpolation. Approximation of
color picture elements with an increase in the size of the
video playback window. In the absence of this function
accelerator image has a characteristic block structure.
YUV - the encoding method of color signal component signal
luminance (Y) and Chroma signals U and V, used in
video equipment and video clips used in MPEG.
Z-buffering - Z-buffering is essential for 3D-accelerator
function. For each picture element is stored coordinate of the
"depth". In accordance with its value of two elements,
superimposed on each other, is depicted next to the plane of
the screen.
In the computer market PC-iron at the moment appears
all sorts of 3D-accelerators. The most preferred of
They are the ones that are made on the Voodoo Graphics chipset
/ Voodoo2 company 3Dfx Interactive, Inc. (Eg, Diamond Monster
3D / Monster 3D II). Also not bad are the following boosters:
Matrox Mystique / Mystique 220; Matrox Millennium / Millennium
II; ATI XPERT @ PLAY / XPERT @ WORK/3D Pro Turbo PC2TV; ASUSTek
3DexPlorer-V3000 / AGP-V3000. In addition, the accelerator can
be as accessories (Add-on) to the graphics card and installed
in an additional expansion slot, and be most video card with
built-in set of specialized chips (Chipset). The first group
includes such accelerators as Diamond Monster 3D and Matrox
m3D. The second group - Diamond Stealth II (recommended only
for games) and NIMBER NINE Revolution 3D "Ticket to Ride" (the
most expensive and fancy card). Selecting the type of card
depends on what you're going to do. If this is the 3D-games,
it's better to buy Add-on, then to not be problems with drivers.
You should only add that despite the power of even the most
expensive accelerators, they are not able to completely
replicate all light and tsvetoeffekty which can easily create a
"naked" Amiga.
