ELSA GLoria-L, Руководство пользователя

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All About Graphics
ELSA GLoria-L, -L/MX, -XL, -XXL
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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
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
Function Direct 3D OpenGL Heidi*
Alpha blending
쮿 쮿 쮿
Texture mapping
쮿 쮿 쮿
MIP mapping
(not for
GLoria-L)
쮿 쮿 쮿
Video motion mapping
쮿 왏 쮿
Fogging
쮿 쮿 쮿
Anti-aliasing filter
쮿 쮿 쮿
Flat shading
쮿 쮿 쮿
Gouraud shading
쮿 쮿 쮿
Phong shading
왏 왏 왏
Stencil buffer
왏 쮿 왏