Jaton 3DForce6200-256, Руководство пользователя

Страница: 20 / 30

3D technology is becoming increasingly important (and common) not only in
games, but also in other applications such as VRML, which allows 3D scene
descriptions in Web applications. 3D technology is used for image editing,
modeling, and an increasing number of in home and business applications. In
games, as well as other applications, 3D acceleration not only allows better
visual qualities and more realistic scenery attributes than software alone, but it
also allows a higher frame rate, which translates into a more interactive
experience for the end user.
Q2 What does “Rendering Engine” mean?
Answer
“Rendering Engine” generically applies to the part of the graphics engine that
draws 3D primitives, usually triangles. In most implementations, the rendering
engine is responsible for interpolation of edges and "filling in" the triangle.
Q3 What does the set-up engine do in a graphics controller?
Answer
A set-up engine allows drivers to pass triangles in the form of raw vertex
information; whereas, most common designs force triangles to be pre-processed
for the rendering engine in terms of delta values for edges, color, and texture.
Q4 Why does a 3D graphics chip need to have both a rendering engine and a
setup engine?
Answer
Any “3D application”, a game, VRML, or modeling package, can benefit from 3D
rendering. This is especially true of an application that uses texturing extensively,
because texturing and texture filtering are very intensive operations at the pixel
level in terms of CPU operations and demands for memory bandwidth. Without a
set-up engine in a graphics controller, the CPU has to calculate the delta values
for edges, color, and textures; the drivers need to handle ten (10) times more
extensive data. This results in slower 3D pipeline operations between the CPU
and the graphics controller.
Q5 If we use powerful CPUs, such as a Pentium™ 200, can a standard 2D
graphics card achieve 3D performance?
Answer
Yes and no. Software rendering can take advantage of "tricks" learned by force of
necessity through years of trial and error. With such stratagems, the speed of
software rendering for simple scenes can approach that of low-level hardware 3D
rendering. On the other hand, as scenes become more complex (or frame sizes
become larger), there are conflicts between using the CPU for high-level game
logic, geometry, lighting, and rendering, all of which increase their demands. No
20