What can anyone tell me about the potential for Phong shading in computer games?

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RobotJesus

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Hi! Have been looking at some screenshots, and Phong shading seems very interesting. Is it used in any games that are out now? Is there anyway to force it in games? How might a 8500 handle it? If there's no way to use it now, when might it become the standard?
Thanks! :)
 
I believe the capability is finally there, but I don't think any games are using it yet. I don't have any current info to answer your question, but knowing how phong shading works, the performance hit would be pretty bad, not to mention compatability issues with older cards. I think we'll be sticking with gouraud shading for a while.

I dream of a day when we can do real-time raytracing. :D
 
I thought that, since Phong shading was about shading by pixels and not vertexes alone, it could be accelerated by 8500's pixel shader capabilities? Or is that a different sphere all-together?
 
RobotJesus said:
I thought that, since Phong shading was about shading by pixels and not vertexes alone, it could be accelerated by 8500's pixel shader capabilities? Or is that a different sphere all-together?
Click to expand...
Hmmm....yeah, I guess that would be the point of vertex shaders, huh? Some of the newer DX 8 games probably do it. I'm stuck in the past. :) Still, it's gonna take a big performance hit and the compatability issue is still there. This thread would probably get a better response from people smarter than me in the 3D coders forum. I'll see if I can find somebody with the power to move it.

edit: Thanks for moving this thread, Andrew.
 
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Nope, no games use it *yet*. The New DOOM is suppose to use it (a Blinn approx model though, still isn't real Phong).
 
I believe we had some information somewhere about how to do Phong shading in a 1.4 pixel shader. There are no plans that I'm aware of to expose the caps bit in the driver which reports phong shading. But either way there are no games written and available on the market today that would make use of this feature. The main reason being that no mainstream parts for a long time have supported it. You may see some developers think about using it but there's so much more they can do with a shader that you'll not likely even see it mentioned.

Jeff
 
Oh. :)
I was mistaken, then -- I thought Phong shading was something which could be used in conjunction with the pixel-shading that can be done by the 8500 line, and not two different processes with one having more benefit than another. :)
Makes sense, though.
I thought that Phong shading was just a technique -- not a process of programming. In the same way that Bilinear and Trilinear filtering can be switched between with no extra programming -- it's a feature on the card.
Thanks for clearing it up! :)
 
Phong shading is merely one algorithm that can be coded using pixel shaders. This example with the green tiled box in the Treasure Chest Demo shows not only Phong shading, but Phong shading with per-pixel normal and a per-pixel specular exponent. In general, going forward, you'll see less "bullet point features" in graphics chips and more examples of how classical algorithms (i.e. Phong shading) can be coded up with shaders.

-Jason
 
I noted that the first time I saw the Treasure Chest Demo.
Although it was jerky, now I'm wondering is that because of the intense calculations underway, my poor system (except for 8500), or sub-par code (i doubt this one)?

--System--
AMD Athlon (Argon) 600mhz
ATI Radeon 8500
FSB 100
256mb PC100
 
I think raytracing is not the answer to the ultimate photo realistic environment problem. Raytracing does work very well on certain types of objects, which can be expressed mathematically precisely such as spheres. The basic raytracing has problems with shadows (they are too sharp), etc, better shadow algorithms require exponentially more time. Probably rendering some objects with raytacing and applying other methods elsewhere will give better results. But raytracing is a method which can easily be parallelized, for ex. to multiple processors or to multiple circuits on ASIC, thus scaling up the performance.

Vahur
 
Nathan said:
I noted that the first time I saw the Treasure Chest Demo.
Although it was jerky, now I'm wondering is that because of the intense calculations underway, my poor system (except for 8500), or sub-par code (i doubt this one)?
Click to expand...

It was jerky when it was first released, but should not be anymore if you make sure you are not running task manager or any other background tasks like that.

Phong shading in a game is very possible today. Another example is here. The room is just 6 pairs of triangles.
 
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