ELSA WINNER 2000/Office, Руководство пользователя

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All About Graphics
WINNER 2000/Office
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In simple terms: They make developers' work easier. The methods by which the various
interfaces function, are comparable: In the past it was necessary to address the various
hardware components directly in programming if you wanted to exploit their capabilities
to the full. The APIs are a kind of translator operating between the hardware and the
software.
The specification of standard definitions was the precondition for the proper function of
these translation routines. These definitions are implemented by the hardware manufac-
turers during development and optimized for the hardware concerned. Developers can
implement complex procedures relatively easily by using these definitions. They can use
a uniform command set when programming and do not need to know the characteristics
specific to the hardware.
What APIs Are Available?
There are a good dozen more or less commonly found 3D APIs. However, in recent years,
three formats have established themselves as the favorites: Direct 3D, OpenGL and
HEIDI. ELSA graphics boards support these commonly found 3D interfaces. The func-
tional differences between the interfaces are slight, as is shown by the table below. The
decisive questions for the user concern extensibility, flexibility and possible portability to
existing applications.
Direct 3D
As a development of Mode X and DirectDraw under Windows 3.1x, Direct 3D is a branch
of the DirectX multimedia family which was developed directly for Windows 95 to accel-
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
Function Direct 3D OpenGL Heidi*
Alpha blending
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Texture mapping
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MIP mapping
(not for
GLoria-L )
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Video motion mapping
쮿 왏 쮿
Fogging
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Anti-aliasing filter
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Flat shading
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Gouraud shading
쮿 쮿 쮿
Phong shading
왏 왏 왏
Stencil buffer
왏 쮿 왏