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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
Software 3D is generally used to mean using non-specific (2D) hardware in
conjunction with the CPU to render for 3D applications. Some of these
techniques allow usable 3D applications when high-powered and/or MMX™-
equipped CPU's are employed along with special-case software optimization
techniques. As stated above, SW 3D can achieve credible results with today's
(software optimized) applications, but the rising popularity of good 3D hardware
at the consumer price level is inexorably compelling the public to expect
hardware level scene enhancements and frame rates.
Q7
What is “SGRAM”?
