Transform and Lighting: The 3d Evolution by Leonard "Viking1" Hjalmarson
	The addition of on board geometry processors was the natural next step in the evolution of PC video hardware. Both S3 (Savage2000) and Nvidia (GeForce 256) have announced products which offload polygon setup from the CPU and do onboard transform and lighting. What I didn't know at the time was revealed to me via our article feedback forum by a helpful individual who is in game software development. Here is an excerpt from his post: Many games support API transform and lighting right now; the games sitting on your hard drive that you play all day. DX7 is not a year away, it's a few weeks away. The reason MS has to update DX7 to support hardware transform and lighting is because of the structure of DirectX. In DirectX, there's a layer imbetween the application API and Driver API, so in effect, driver authors are limited by what microsoft allows for in this middle layer. MS didn't allow for drivers to accelerate the transform and lighting in DX6. But, once DX7 and a driver/hardware capable of accelerating T&L are installed, even games that use the DX6 API will receive the accelerated transforms. This is one of the cases where MS's COM actually is pretty nice. Let me say that again, on a system with DX7 and hardware accelerated transforms, DX6 games WILL have their tranforms accelerated. The exception is games that do their own transforms in engine instead of in API. I unfortunately don't know really how many DX games do this.. most OpenGL game programmers have followed Carmack's lead and stayed with API transforms, or at least made their engine transform pipeline defeatable. Games that don't use API transforms can in most cases be easily patched. WOW! "Games that we have on our hard drives NOW" may immediately benefit from DX7, and many others can be readily patched. I was amazed, and immediately fired off a round of emails to game developers to survey which current and near products will benefit by onboard geometry processors. (The nearest video hardware release with an onboard processor is the Guillemot 3d Prophet, only weeks from release.) Name the Games Answers began flowing back the next morning. Teut at WingsSimulations, Executive Producer of Panzer Elite, said that they chose to write their own transforms into the API because they could do it twice as fast as DX6. Panzer Elite would have to be patched for DX7. Similarly, Robin Heydon at Microprose confirmed that the transforms and lighting are written into Falcon 4. However, he also confirmed that with the release of F15 next year, Falcon 4 would be patched to DX7 and so benefit from onboard transforms and lighting. "What hardware T&L will provide is the ability to draw more objects. This will provide more buildings in cities, more tanks, and higher detailed objects in the foreground." Click to continue . . .		F15 in USAF We wrote to Pixel Multimedia, developers of USAF with the same question. It turns out this one is a big YES!! USAF only does a small part of the transforms in the code and will benefit greatly by onboard geometry processors! The producer of Flight Combat reported that major parts of the game will use accelerated transformation. There are about 5 major graphical pipelines in the game, most are good candidates but some aren't (for example, the 3d models are a very good candidate, but for various technical reasons the terrain isn't.) P51 in B17 II Jonathan Newth, CEO of SIMIS wrote us that Team Alligator has just been moved to DX7 and currently runs with their own software T&L. However, a modified TA was running on an early DX7 to prove the benefits of T&L on 3DLabs hardware, and SIMIS is now working on adding full support into the engine so that NVidia, S3, 3DLabs and anyone else with onboard geometry will accelerate Team Alligator transforms and lighting. Team Alligator I also wrote to Mindscape inquiring about Flanker2 T&L. I suspect that since Flanker also runs under OpenGL that some portion of the transforms are written to the API. If that is the case, then the release of DX7 will provide accelerated transforms on hardware with onboard geometry processing. Join a discussion forum on this article by clicking HERE.
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