Scan frequency:
Horizontal scan frequency : The number of lines illuminated on a video screen
in one second. For example, a resolution of 400 lines refreshed 60 times per
second requires a scan rate of 24 kHz plus overhead (time to bring the beam
back to the beginning of the next line). Same as horizontal sync frequency in
TV. Contrast with vertical scan frequency. Vertical
scan frequency : Also called "refresh rate," it is the number of times an entire
display screen is refreshed, or redrawn, per second. Measured in Hertz, display
systems typically range from 56Hz to well over 100Hz. A minimum of 70Hz is recommended
to help prevent eye strain. Contrast with horizontal scan frequency.
SDRAM (Synchronous
Dynamic Random Access Memory):
A memory type, that is faster than DRAM. It synchronizes
all memory access requests according to the microprocessor's internal clock.
Shading:
The process of interpolating color within the
interior of a polygon, or between the vertices
of a line, during rasterization.
Sideband
signalling:
This is an extra 8-bits of transfer capability
built into AGP so that an AGP graphics board can request
information at the same time as it is receiving other information.
16-bit/64-bit:
1. The processing power of a chip or system. The processor
can handle this many bits of information at once.
2. May also designate the width of a bus or data path.
3. Used to describe graphics power (e.g. 16-bit color = 65,000 colors).
Specular
reflexion (specular highlighting):
In a 3D image, reflections
of light sources on shiny materials, such as metal.
Sprite:
A 2D on-screen graphic object. It is possible
to manipulate it without affecting the background images.
Stencil
buffer:
This is an extra buffer containing special
information concerning pixels as to whether to draw
them or not. Its feature is particularly useful in creating special effects
such as shadowing from multiple light sources. These buffers calculate a cutout
effect, masking part of an image to apply a more precise transformation to the
rest. Another function would be to mask part of an image so that the chip
only calculates the rest.
SVGA
(Super Video Graphics Array):
A graphics standard
starting from display resolutions of 640x480 at
256 colors.