GLINT Delta v. Pinolite
3-June-1998
by Ian D. Romanick (idr@cs.pdx.edu)
Over the past few days I have read numerous articles on the web that compare
the Fujitsu Pinolite to the 3Dlabs GLINT Delta. This is a totally illogical
comparison to make. Although both chips carry the "geometry accelerator"
designation, they have very few similarities. In fact, their similarity
ends at the fact that they are both hardware attempts to accelerate 3D
rendering.
In the future, however, they may have one additional similarity. The
Pinolite may join the GLINT Delta as a product that made big claims but did
not provide the performance that gamers need or receive the support it needs.
The 3Dlabs GLINT Delta
Although 3Dlabs would like the buying public to believe the GLINT Delta is a
geometry accelerator, it simply is not. The 3Dlabs GLINT Delta is a hard coded
polygon setup engine. 3Dlabs says that the GLINT Delta "reduces load on CPU and
Bus" and that it performs "vertex sharing for meshes, fans and polylines" [1]. The GLINT Delta achieves this by performing "slope
and setup calculations for line and triangle primitives" [2]. These features sound very nice, but other 3D
accelerators, such as the 3Dfx Voodoo, also have them in hardware.
The Fujitsu Pinolite
Fujitsu's Pinolite processor, on the other hand, is a specialized DSP with
dual PCI interfaces. Because of its generalized implementation, this chip
could be used for non-graphics applications. However, the Pinolite was
designed with 3D in mind. As evidence of the chip's generality, one of
Fujitsu's press releases announced that a C compiler would be made available
for the chip [3]. It is up to users of the chip to
determine how to put it to work.
The Pinolite could be used in a wide variety of ways. In a fast system with
a 3D accelerator that is not fill-rate bound, such as a Pentium II 300 with
a Voodoo2, the Pinolite could be used as to perform collision detection
while the main CPU was feeding graphics information to the 3D accelerator.
On a slower system with poor floating point performance, the Pinolite could
be used to perform some of the final lighting and clipping operations. If
used in conjunction with a 3D accelerator that does not perform triangle
setup, the Pinolite could do the same setup operations that the GLINT Delta
does.
In fact, this flexability may the Pinolite's downfall. The Pinolite, and
similar products that may be available in the future, should be able to
provide performace improvments to nearly the whole range of PCs. However,
the way that a developer (or driver writter) will need to use the chip
changes with the speed of the host CPU. A Pentium II 400 based system would
want to use the Pinolite differently than an AMD K6 200. Now instead of
having to support many devices in the same way, the developer is forced to
support the same device in many ways.
Conclusion
Fujitsu's Pinolite and 3Dlabs' GLINT Delta a very different chips that both
carry the title "geometry accelerator." The GLINT Delta is an early
generation chip that provided features that are now standard in 3D
accelerators. The Pinolite is a specialized DSP that is optimized to work
in conjunction with a conventional 3D accerator. The Pinolite has the
potential to improve the performance of a wide variety of PCs, but driver
and game developers will have utilize the chip in potentially different ways
depending on the performance of the main CPU. This may limit the Pinolite's
ability to gain needed support from developers.
References
1. 3Dlabs product overview for
Permidia2 w/GLINT Delta.
2. 3Dlabs product overview for
GLINT Delta.
3. Fujitsu press release 1997-0139,
July 2, 1997.