[X]   Directory of
Guides & Reviews

Beginners Guides
Motherboards by Brand
Weekly Newsletter
Archived Newsletters

ULTIMATE Video Card Guide
New games demand more of video cards and their memory; bigger textures, more triangles, and various other new means of hardware acceleration to look good and still run at playable speeds.
Filed under: Video Cards Published:  Author: 
External Mfg. Website: Various Jul 18 2000   D. Dee  
Home > Reviews > Video Cards > Various

More present and future hardware features

More present and future hardware features

Making lines look smooth isn't the only concern when it comes to how good a scene looks. Games are more impressive when more polygons are used for the objects in them and when hardware technologies are used to make lighting and surfaces look better. This is where things like hardware transform and lighting, environment mapping, and per-pixel shading come into play. Hardware transform and lighting, or T&L, has, of course, two parts. The transform part takes over the object geometry processing, while the lighting component handles the various light sources in the game or application environment. If the CPU had to do this stuff, a big performance hit would result, but with the special hardware on the video card it's no problem.

These features allow a chip with T&L to produce much more realistic scenes, with objects that are less blocky and more detailed since far more polygons can be used. Systems without dedicated T&L hardware could still theoretically render the same stuff, but the CPU would be doing all that work, and the performance hit would be unacceptable. The drawback to T&L is that games and applications must be specifically coded to take advantage of its features, so older games won't benefit from it. Currently there are hardly any games that use T&L at all. Quake 3 Arena does to some extent, and Soldier of Fortune should benefit much more from it as apparently much of it was coded with hardware T&L in mind. But to my knowledge those are the only two that use it. There are numerous games in the works that will support hardware T&L, but for the most part this feature is only something that will make a significant difference in the months ahead.

Hardware T&L was introduced on nVidia's GeForce 256 cards, called GPUs (Graphics Processing Units) mostly by marketing people. The GeForce2 GTS's T&L unit is, not surprisingly, improved over that of the older GeForce 256's. S3's Savage 2000 chip also has hardware T&L on it, but it's inferior to that on nVidia's cards and wasn't active at all in initial driver releases. I'm pretty sure newer Savage 2000 drivers at least partially use the chip's T&L capabilities.
Several types of environment mapping techniques are implemented in some of today's video cards.

Matrox's G400 uses environment mapped bump mapping, which basically makes a texture look three-dimensional by altering how light reflects off of it: it tricks the eye into thinking the surface has depth. Water scenes benefit much from this technique, since bump making can make it look like the water is rippling. Static surfaces, like walls, can be made to look like they have chips or other imperfections in them. The GeForce cards support cube environment mapping, which also deal with light reflections. Cube environment mapping allows objects to have glossy or rough-looking surfaces. It doesn't seem to be as flexible as environment mapped bump mapping, but it's still quite useful for increasing realism.

The GeForce2 GTS has an extra feature that the GeForce 256 lacks: per-pixel shading and, thus, per-pixel bump mapping. As you might guess from its name, per-pixel shading handles in hardware all lighting calculations for each individual pixel. Because it handles it for each pixel, bump mapping can be achieved.
Unfortunately, these environment mapping methods, like T&L, must be supported in the game or application code, so again only programs written to use them will benefit. However, there are already several games that support environment mapping, and more are on the way.
Because they allow scenes to look so much more realistic, I expect that all these techniques will be commonplace on video cards next year and will hopefully be supported by most, if not all, new games.

< Previous Page © 2023 PCSTATS.com Next Page >


Contents of Article: Various
 Pg 1.  ULTIMATE Video Card Guide
 Pg 2.  NVidia's chips
 Pg 3.  Diverging Paths
 Pg 4.  Present and future hardware features
 Pg 5.  — More present and future hardware features
 Pg 6.  Interfaces
 Pg 7.  Keeping up
 Pg 9.  More players

Hardware Sections 

PCSTATS Network Features Information About Us Contact
PCSTATS Newsletter
Tech Glossary
Technology WebSite Listings
News Archives
(Review RSS Feed)
Site Map
PCstats Wallpaper
About Us
Privacy Policy
Advertise on PCSTATS

How's Our Driving?
© Copyright 1999-2023 www.pcstats.com All rights reserved. Privacy policy and Terms of Use.