es. Combined with the processing demands of shading, lighting, and texture mapping, complex 3-D can very quickly bog down even a fast Pentium.
The NVIDIA technology creates 3-D models from a quadratic (i.e., four-sided) curved surface. Each quadratic surface has nine control points: four at the corners, four at the side midpoints, and one at the center. The control points can shape the surface either by warping it (by creating ellipses in 2-D space) or by pulling it out from the center to create complex curves in 3-D space. NVIDIA's quadratic surfaces require far fewer transformations than traditional 3-D approaches, because the surfaces can be molded to better represent a 3-D shape.
If the shap
e is complex, the NVIDIA engine creates additional control points to mold the quadratic surface more precisely. The Edge 3D accelerator also implements perspective correction and lighting effects in hardware for improved realism and performance. Forward texture maps are stored in host memory to lower video memory costs.
The drawback is that developers must create titles that specifically support quadratic surfaces. But once the port is done, the results are outstanding. The Virtua Fighter game we tested with the Edge 3D ran at 800- by 600-pixel resolution in 16-bit color, full-screen and fully textured at 30 frames per second, and without any noticeable jerkiness or flagrant pixelation.
You can also apply motion-video textures to 3-D objects; for example, the demo CD included a 30-fps Audio Video Interleave (AVI) video mapped onto a 3-D object that we could rotate in space. With this type of capability, future titles should display even greater creativity and special effects.
We installed
the board on a 90-MHz Pentium and enjoyed all the benefits of Windows 95 Plug and Play. We popped the card into a PCI slot, connected the Sega controller bracket, and booted Windows 95. Windows 95 automatically detected the new hardware and asked for a driver. We pointed it to the installation CD, and that was it.
Prices for the Edge 3D start at $249 for 1 MB of DRAM. We tested it on a board with 2 MB of video memory. Bundled titles include Descent: Destination Saturn, Nascar Racing from Papyrus, and Virtua Fighter Remix. Other titles are in development. The Edge 3D also ships with multimedia utilities, a demo CD, and MPEG playback software from Mediamatics.
screen_link (53 Kbytes)
The Diamond Edge plays specialized versions of Sega Saturn games.
Diamond'S New Edge
