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.