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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 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
