ELSA Synergy II, Руководство пользователя

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Glossary
ELSA SYNERGY II
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Multifrequency/Multisync monitor – A
monitor that can be operated at various hori-
zontal scan frequencies, or that automatically
adapts itself to different video signals (resolu-
tions).
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OpenGL – 3D software interface (3D API).
E.g. implemented in Windows NT and avail-
able for Windows 95. Based on Iris GL from Sil-
icon Graphics and licensed from Microsoft.
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Page Flipping – The image generated in the
➞
back buffer is displayed
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PCI bus – Abbreviation of Peripheral Compo-
nent Interconnect Bus. An advanced bus sys-
tem, i.e. a system of parallel data lines to
transfer information between individual system
components, especially to expansion boards.
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Phong shading –
➞
'Shading'.
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Pixel – Picture element. Dot in the image.
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Pixel frequency – Pixel clock frequency
(number of pixels drawn per second in MHz).
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Primitive – Simple, polygonal geometrical
object, such as a triangle. 3D landscapes are
generally broken down into triangles.
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RAM – Abbreviation of Random Access Mem-
ory. Chip memory of a computer or expansion
board that can be read from and written to
(unlike ROM = Read Only Memory).
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RAMDAC – The RAMDAC converts the digital
signals to analog signals on a graphics board.
VGA monitors are only capable of processing
analog signals.
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RealColor – RealColor normally designates a
15-bpp or 16-bpp (bits per pixel) graphics mode,
i.e. 32,768 or 65,536 colors).
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Refresh rate – or image refresh frequency (in
Hz) indicates how many times per second an
image on the monitor is refreshed.
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Rendering – Process for calculating the repre-
sentation of a 3D scene, in which the position
and color of each point in space is determined.
The depth information is held in the
➞
Z buffer,
the color and size information is held in the
➞
frame buffer.
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Resolution – The number of pixels in horizon-
tal and vertical direction on the screen, for
example 640 horizontal by 480 vertical pixels
(640 x 480).
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RGB – Color information is saved in the Red/
Green/Blue color format.
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ROM – Abbreviation of Read Only Memory.
Semiconductor memory that can only be read
and not written to.
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Shading – Shading or rendering is a way to
define the colors on curved surfaces in order to
give an object a natural appearance. To
achieve this, the surfaces are subdivided into
many small triangles. The three most impor-
tant 3D shading methods differ in the algorithm
used to apply colors to these triangles:
Flat shading: the triangles are uniformly col-
ored.
Gouraud shading: The color shades on a trian-
gle are calculated by interpolating the vertex
colors, resulting in a smooth appearance of the
surface.
Phong shading: the color shades on a triangle
are calculated by interpolating the normal vec-
tor.
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Single buffer – By contrast with double buff-
ering, where the image buffer is duplicated, the
single buffering mode is not able to access the
next image, which has already been calculated.
This means that animations will run jerkily.
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Tearing – A distinction is made in double
buffering between the front buffer and the back
buffer. The image change between the front