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“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 applications
that use 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
Software 3D is generally used to mean using non-specific (2D)
