ELSA Erazor II, Victory Erazor LT user manual OpenGL, Immediate Mode and Retained Mode

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All about graphics 17

erate the slow 3D display characteristics of the operating system. Direct 3D is based on Microsoft's Common Object Model (COM), which is also used as the foundation to OLE technology (Object Linking and Embedding). Direct 3D cooperates with Direct Draw in two-dimensional display. A typical situation would be, for instance, rendering a 3D object while Direct Draw is placing a two-dimensional background bitmap. Microsoft claims to have corrected some of the weaknesses of the old version in the most recent version 5.0.

Immediate Mode and Retained Mode

As can be assumed from the two terms, immediate mode is a programming mode that is close to the hardware. Retained mode, on the other hand, is a programming mode that is largely predefined through an API interface. What does this mean in detail? Looking at the two systems hierarchically, the immediate mode is also known as the low-level mode. The programming interface level is close to the hardware level and permits the programmer direct access to special functions in the hardware component concerned. The retained mode (high-level mode) makes it possible, for example, to load a defined 3D object with textures into a Windows application. Here it can be manipulated and moved using simple API commands. Translation takes place in real time, without the need to know the technical structure of the object.

For further information see the Internet WWW site http://www.microsoft.com

OpenGL

Following its success in gaining a good reputation amongst professionals using CAD/ CAM programs, OpenGL is now increasingly penetrating the PC market. OpenGL is plat- form-independent and makes a distinction between immediate and display list modes. A display list stores specific sequences that can be recalled again later. The object descrip- tions can then be taken directly from the list, resulting in very high performance. How- ever, if objects need to be manipulated frequently, the display list will have to be generated again from new. In this case, the speed advantage is lost. OpenGL provides a wide range of graphics features, from rendering a simple geometric point, line, or filled polygon, to the most sophisticated representations of curved surfaces with lighting and texture mapping. The some 330 routines of OpenGL provide software developers access to these graphics capabilities:

For further information see the Internet WWW site http://www.sgi.com

ELSA ERAZOR II and ELSA VICTORY Erazor LT

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Contents Elsa Erazortm Germany Elsa IncSonnenweg AachenThank you for placing your trust in this Elsa product PrefaceAbout this Manual Changes to this ManualBefore you continue Contents Glossary Index Look at the Erazor II and Victory Erazor LT IntroductionWhats In the Box? Highlights of the Erazor Graphics BoardsWhat Hardware Do I Need? CE and FCC CE Conformity and FCC Radiation StandardDeclaration of Conformity Introduction Elsa Erazor II and Elsa Victory Erazor LT Colors HighColor TrueColor After Installing the DriversWhat is Possible? Its Time to Get MovingMonitor Typical Minimum Maximum Ergonomic ResolutionWhat Makes Sense? More pixels means more funWindows 95 and Windows Changing the resolutionClick on Start, then select Settings E Control Panel Choosing the monitor Here you should click on the Settings tabElsa Erazor II and Elsa Victory Erazor LT Windows NT Use the command sequenceStart E Settings E Control Panel Multimedia Player Useful Stuff and MoreTurn Settings E Advanced... E 3D Settings Fine-Tuning for Performance FreaksStart The object data All about graphics3D Graphics Representation 3D PipelineRendering Geometrical transformationFlipping Display on the monitor Frame bufferDirect 3D 3D InterfacesWhat APIs Are Available? OpenGL Immediate Mode and Retained ModeBpp Color Palettes, TrueColor and Gray ScalesDirectColor HighColor and RealColorThere are various standards DDC1, DDC2B, and DDC2AB Vesa DDC Display Data ChannelTrueColor DDC2AB O addresses Technical DataCharacteristics of the Graphics Boards Address Assignment of the Erazor IIPin Assignment Connection SignalPorts on the Graphics Board VGA D-Shell SocketAppendix Advice and HelpName and version of the application program with the error Who to Contact? Elsa Japan Inc Driver Updates Repair?Elsa LocalWeb DoC-Declaration of Conformity Appendix Elsa Erazor II and Elsa Victory Erazor LT Warranty Procedure Warranty ConditionsWarranty Coverage Warranty PeriodAdditional Regulations Operating MistakesAppendix Elsa Erazor II and Elsa Victory Erazor LT Glossary 3D Three-dimensionalFlipping The image generated in the back buffer is displayed Pixel Picture element. Dot in the image Phong shading ShadingAre calculated by interpolating the normal vec- tor 15, 32 Index18, 19