“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 current CPU or system can perform advanced quality-
enhancements (bilinear filtering and alpha blending) in real time. Even
general case texture mapping with RGB lighting is too much for the
current CPU generation.
Q6
What does "software 3D" mean?
Answer
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