November 21, 2017
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ATI Technologies
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ATI Radeon 8500
August 14, 2001 | Michael Eilers

There are even some really amazing (and esoteric) features included such as the ability to flip and mirror the video image so that it turns out right-side up with some types of video projection devices, and the ability to “genlock” the screen refresh rate to a camera so that the screen can be filmed without banding or flipping.

The card is HDTV-ready, and can drive any digital or analog-based high-definition monitor that will support DVI or a DVI adaptor. In addition the card has the usual S-video port, which will connect with most current VCRs and many current televisions. The thought of this card hooked up to a Phillips 50-inch plasma display playing Q3A at 1920x1080 is enough to give one pause, is it not?

ATI just released the Radeon VE, a card with dual monitor support, but the 8500 will have this feature included “for free.” This is true mix-and-match support, meaning that you can drive numerous combinations of video output devices. For instance, you could hook a flat-panel display to the DVI port, an analog monitor to the VGA port and mirror the main monitor signal to the S-Video port (connected to a television or VCR) simultaneously and get hardware acceleration on all screens. This would take 2 or 3 PCI slots with the previous generation of cards. Hydravision incorporates all of the 2D features in the Video Immersion Engine II, of course.

While ATI has had competitive video card offerings for quite some time, one area in which they clearly lagged behind the competition was support for anti-aliasing, the real-time “smoothing” of edges and artifacts created by video rendering. A discussion of anti-aliasing methods, advantages and drawbacks could comprise an entire article in itself, so I am going to dramatically simplify the discussion for the sake of brevity.

Here’s a quick summary: 3dfx opened the door to full-scene anti-aliasing with their Voodoo5 card, which used multiple renders of the scene overlaid upon each other to create a smoothed image. NVIDIA countered first with a driver-level FSAA implementation and then a hardware method known as Quincunx, which uses a multisampling grid pattern to blend pixel colors and hide hard edges on the screen. In this scenario ATI has benefited by being last, as they were able to learn from the strategies that their predecessors followed.

3dfx’s “rotated grid supersampling” was gorgeous, but far too costly in memory use and fill rate – it cut game frame rates in half (or worse) in most situations. NVIDIA’s Quincunx method is highly praised, but only looks as good as 3dfx’s method when you also run very high resolutions (1280x1024 and above) which also limits peak frame rate and increases the CPU burden of the game.

ATI chose a third route with Smoothvision. Using the random sampling methods pioneered by 3dfx but reducing the number of samples required, their version claims to give a more natural smoothing effect without killing your fill rate. And they took this one step further by making the very first programmable AA engine, allowing developers to expand and configure the Smoothvision effect on-the-fly. Via specialized features of Direct 3D 8.1 and OpenGL, Smoothvision rendering can even be used for special effects such as depth of field and motion blur -- hardware-accelerated blurring of selective areas of the screen.

The result should be a full-scene anti-aliasing method that does not clog the card’s RAM or GPU while creating a naturally smooth look free of grid artifacts. In addition to scene anti-aliasing, Smoothvision also supports edge and line smoothing for such applications as 3D modeling and CAD/CAM solutions. Unfortunately ATI did not provide any sample images of Smoothvision in action with their press kit.

FSAA is a touchy issue with Mac gamers; neither the ATI or NVIDIA cards available to us currently support FSAA of any kind, due to driver limitations. In our conference call with ATI we was assured repeatedly that Mac users will not be skipped this time around, and that Apple’s OpenGL implementation is being actively co-developed by ATI team members and Apple to incorporate the full feature set of the 8500 in a future driver update.


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