1 3d – three-dimensional.

    2 3d clipping – a process within geometric transformation in which invisible areas or portions of a 3d object are removed.

    3 3dnow! – extended command set used by amd in the k6-2, k6-3 and k7 processors. 21 additional commands are intended above all to accelerate the floatingpoint operations that are especially important for 3d games.

    4 3d pipeline – the sum of all steps required in displaying an imaginary 3d scenario on the monitor. included in this are → geometrical transformation and → refresh rate.

    5 agp bus – abbreviation for accelerated graphics port—a relatively new interface standard within the pc platform. graphics boards take advantage of its high transfer rates for the display of 3d and full-motion video sequences.

    6 aliasing – the well-known staircase effect. there is often a jagged transition between adjacent pixels when displaying slanted or curved lines. the rough transitions can be smoothed using anti-aliasing.

    7 alpha blending – supplementary information per pixel for generating transparent material.

    8 anisotropic filtering – method designed to reduce texture aliasing effects on surfaces at an angle to the viewer. unlike other methods (such as → bilinear filtering, → trilinear filtering) anisotropic filtering takes into account that such surfaces require a greater number of texture pixels for a clean display than surfaces that are perpendicular to the viewer. this especially enhances the legibility of text on angled planes (“star wars text”).

    9 anti-aliasing – methods for the reduction of → aliasing effects.

    10 api – application programming interface. software interfaces that provide applications with complete packages of functions. the most important 3d apis are → direct3d and → opengl

    11 back buffer – a portion of the graphics memory that is used to construct the image that is to appear on the monitor next. the back buffer is also used to calculate transparency effects.

    12 back-face culling – leaving out invisible areas.

    13 bilinear filtering – in this case, a weighted average is calculated from four neighboring → pixels or → texels (2x2 matrix).

    14 bios – abbreviation for basic input/output system. a code stored in the computer's memory (rom), which carries out the self test and various other functions when the system is started.

    15 blitting – traditional method for → buffer swapping: the contents of the → bump mapping is copied to the → front buffer; slower than → page flipping.

    16 buffer swapping – the image prepared in the → bump mapping is displayed.

    17 bump mapping – a technique that provides textures with depth information, which can be applied to display relief or embossed structures.

    18 bus system – a system of parallel conductors for transferring data between individual system components, especially to expansion cards, such as isa → page flipping and → agp bus.

    19 chrominance – color information in the transfer of video signals.

    20 clipping – reduces the number of → primitives to be calculated. all primitives outside the limits of the screen (2d) or outside of the → viewing pyramid (3d) are clipped or removed.

    21 cube environment mapping – in order to represent realistic and undistorted reflections of the environment onto an object, six → textures are viewed as the surfaces of a cube. the textures show the environment from the perspective of the object. this gives the impression that the environment is being reflected by the object. cem is an extension of sphere environment mapping. the advantage of cem is that no new textures need to be calculated when the observer's point of view changes and the texture is not distorted.

    22 d/a converter – digital/analog converter: a signal converter that converts digital input to analog output.

    23 ddc – abbreviation for display data channel. a special data channel through which a ddc-capable monitor can send its technical data to the graphics board.

    24 ddr sdram – double data rate sdram is a further development of → sdram memory technology. while sdrams only provide data at the actual system clock speed, ddr chips permit data to be accessed at twice the system clock speed.

    25 direct3d – software interface (→ api) developed by microsoft for the manipulation and display of 3d content.

    26 directcolor – method to achieve the high-resolution → highcolor, → truecolor and → realcolor graphics modes. in this case, the value stored in the video ram (→ vram) is not translated but is passed directly to the d/a converter → d/ a converter. this means that the full color information must be saved for each → pixel.

    27 directdraw – software interface (→ api) developed by microsoft for the display of 2d content such as videos.

    28 double buffer – describes the presence of doubled display memory. this permits the next image to be generated first in the invisible background (v bump mapping). as soon as it is completely constructed, the monitor display switches to the image that has been residing in the background and the preparation of the next image begins on the other side.

    29 dpms – abbreviation for → vesa display power management signaling. this allows several stages of monitor powersaving mode. the graphics boards described in this manual support vesa dpms.

    30 dram – abbreviation for dynamic random access memory. dynamic random access memory with direct access. edo-ram – abbreviation for extended data output random access memory (hyper page mode). edo-ram is especially advantageous in graphics boards becausethe most recently required data remains held in memory. image rendering involves multiple consecutive read access of similar data, so edo-ram results in significantly faster speeds.

    31 fcc – the fcc radiation standard states that this device has been tested and meets the requirements for digital class b devices in accordance with section 15 of the guidelines as provided by the american federal communications commission (fcc).

    32 fifo method – abbreviation for first in, first out: a system used in batch processing and queues, in which the first arriving signal is processed first.

    33 fixed-frequency monitor – a monitor that can only be operated with at a specific resolution and refresh rate.

    34 flat shading – → shading

    35 frame buffer – memory on the graphics board containing display information, especially the → front buffer and → bump mapping

    36 front buffer – refers to the visible image area in the case of → double buffer.

    37 full-scene anti-aliasing – describes a type of → anti-aliasing that is applied to a complete frame. two processes are used in this form of anti-aliasing: super sampling and accumulated buffers. in the case of super sampling, a much higher resolution is calculated than the one to be displayed and then reduced. with the accumulated- buffer process, several views of a scene are drawn that are then combined to a single image.

    38 geometrical transformation – the position of the objects in space is determined based on the observer.

    39 gouraud shading – → shading

    40 graphics accelerator – elsa synergy 2000 is a graphics accelerator board that is especially well-suited for the user environment that requires intense graphics.

    41 highcolor – stands for a graphic display mode with 15 or 16 bit color depth per pixel (32,768 or 65,536 colors).

    42 horizontal frequency – the monitor line frequency (horizontal scan frequency) in khz. this value must be set according to the monitor's requirements to prevent the monitor from being damaged in extreme cases!

    43 horizontal scan frequency – the monitor line frequency in khz. this value must be set according to the monitor's requirements to prevent the monitor from being damaged in extreme cases!

    44 interpolation – when displayed, video data must be stretched or shrunk to thecorrect window size. if the individual pixels are simply multiplied when stretched, unwanted blocks (the staircase effect, → aliasing) occur. this can be prevented using a filtering interpolation technique (averaging). while horizontal interpolation is easily accomplished, vertical interpolation is more complicated and requires buffered storage of the most recent image lines.

    45 isse – extended intel command set currently used in the pentium iii processors. 70 additional commands are intended above all to accelerate the floating-point operations that are especially important for 3d games.

    46 luminance – black/white information in the transfer of video signals.

    47 mip mapping – mip mapping assigns several textures with different resolutions to an object based on distance. if the observer gets closer to the object, the representation of the texture becomes more detailed.

    48 mmx – extended intel command set used by 166 mhz and higher pentium processors bearing this designation. 57 additional commands accelerate especially integer operations.

    49 multifrequency (multisync) monitor – a monitor that can be operated using different line frequency ranges and can adjust itself to different image signals (resolutions).

    50 opengl – 3d software interface (3d api). such as implemented in windows nt and optionally obtainable for windows 95, this is based on iris gl from silicon graphics and is licensed by microsoft and elsa.

    51 page flipping – in the faster page flipping method, only the buffer addresses are exchanged. the slower method (→ blitting) copies the contents of the → back buffer to the → front buffer.

    52 pci bus – abbreviation for peripheral component interconnect bus. a system of parallel conductors for transferring data between individual system components, especially to expansion cards.

    53 phong shading – → shading

    54 pixel – a picture element pixel frequency – pixel cycle frequency: the number of drawn → pixel per second in mhz.

    55 polygonoffset – → z biasing primitive – simple, polygonal, geometric objects, such as triangles. in most cases, 3d landscapes are broken down into triangles.

    56 ram – abbreviation for random access memory. main memory and memory expansion in → vram or → dram depending on the graphics board.

    57 ramdac – on a graphics board, ramdac is responsible for converting digital signals into analog signals. vga monitors can only process analog signals.

    58 realcolor – in general, stands for a 15 or 16-bit-per-pixel-wide graphic display mode (32,768 or 65,536 colors).

    59 refresh rate – indicates (in hz) how often the image on the monitor is rebuilt per second.

    60 rendering – the calculative process for representing 3d scenery, where position and color are determined for each point in space. the depth data are located in the → z buffer while the color and size data are in the → frame buffer.

    61 resolution – the number of pixels in both horizontal and vertical directions (e.g. 640 horizontal x 480 vertical pixels). rgb – color data stored in red/green/ blue format.

    62 rom – abbreviation for read only memory. solid state memory that can be read from only.

    63 s-video – or s-vhs. a method of transferring video data signals, where the signals for → chrominance and → luminance are separated. this results in improved image quality.

    64 sdram – synchronous dynamic random access memory. these memory chips are based on standard drams (→ dram), but are fast enough to permit data access at the clock speed of the → bus system. this eliminates the wait states typical of drams. they consist of two separate memory ranges, with one preparing data for access while the other is actually still being accessed.

    65 shading – the shading of curved areas to make them appear as realistic as possible. to do so, the curved areas are divided into many small triangles. the three most important 3d shading methods differ by how the color gradients within the triangles are represented: flat shading: the triangles are colored uniformly. gouraud shading: the color gradient is determined by the interpolation of the corner color values. phong shading: the color gradient is determined by the interpolation of the normal vector plus the calculation of the light incidence for each pixel. these shading methods are not supported directly in the standard opengl api.

    66 single buffer – unlike the → double buffer, where there is doubled display memory, single buffer mode does not allow access to the next prepared image, resulting in animation that is not smooth.

    67 sphere environment mapping – → cube environment mapping.

    68 stencil buffer – this buffer permits the color information of the → pixel to be supplemented with further information. this can be used to create stencils, volumetric shadows and reflective surfaces, for example.

    69 strips and fans – process for the reduction of data volume required for complex 3d objects. strips are used for objects consisting of several parallel rows of triangles. rather than calculating each individ- ual triangle, the vertices are transferred only once. a fan object is used when several triangles converge to a single point. in this case, the vertices are also transferred only once. these processes can reduce the data volume by approximately a third.

    70 tearing – if there is no synchronization with the monitor when switching between images (pages) in → double buffer mode, areas of the images can become offset. to resolve this, the switching between pages is synchronized with the monitor frequency (wait on vertical blank).

    71 tesselation – tessellation subdivides objects into polygons (e.g. triangles) for 3d rendering. for these primitives, the corner point and color values as well as the transparency value if necessary are determined. tessellation is currently performed by the application, i.e. upstream of the → 3d pipeline.

    72 texel – individual pixel of a → texture.

    73 texture – the overlaying of a surface with a texture with correction for perspective,such as a wood grain or the drawing of a wall with wallpaper in a perspective view. videos, too, can be used as a texture.

    74 transformation & lighting (t&l) – using t&l, the main computer processor is freed up from the consuming task of computing geometric calculations. this computational process, which includes all of the coordinates of a 3d object during rotation, shifting, scaling and color, is taken over by the graphics board processor.

    75 trilinear filtering – this is a mixture of → mip mapping and → bilinear filtering.

    76 truecolor – a graphic display mode with max. 16.7 million colors, i.e. a color depth of 24 or 32 bits per pixel.

    77 vesa – abbreviation for video electronics standards association. a consortium for standardizing computer graphics.

    78 viewing pyramid – designation for the part of a 3d space located within the viewer's field of vision.

    79 vram – abbreviation for video ram. a module for upgrading the memory on a graphics board to display higher resolutions and color depths.

    80 z biasing – → ddr sdram method for the correct display of various objects with the same depth coordinates. a typical example is the display of a shadow on a wall: both objects have the same z (depth) coordinates, but the shadow must appear on the wall (not vice versa). the included z bias value ensures the correct display. under → opengl, this functionality is called polygonoffset.

    81 z buffer – the 3d depth information of a pixel (the position in the 3rd dimension).