What's cool about DX9: HLSL, PS 2.0

[duffer]

Well, now that the DX9 beta is public, we can share our thoughts about it without breaking any NDAs.

I think that the following features are the coolest parts of DX9:

+ Floating Point pixel pipeline.
+ Being able to write to multiple render targets. (Good for multi-pass.)
+ HLSL, which is essentially an optimizing vendor-neutral cg compiler.
+ HLSL and shader debugger.

If developers use HLSL, and they compile their shaders at run time, then it's possible for games will automatically take advantage of newer hardware to a greater degree than they have in the past.

HLSL isn't perfect -- it won't automatically multi-pass for example -- but it's very good. Certainly better than cg.

I think that ATI's got this generation of video cards sewn up, at least for use as a game developer's main card. The NV30 is better on paper, but not better enough to attract serious developer support for the additional features. The situation is similar to what happened with the GeForce 3 vs the Radeon 8500, only with the roles reversed.

 

[Randell]

is that because the hardware and software is there now for R300? Surely for developers NV30 isnt as far away as is it is for consumers.

 

[andypski]

+ HLSL, which is essentially an optimizing vendor-neutral cg compiler.

I prefer to think of CG as a possibly optimising, vendor-specific proprietary HLSL myself.

I say possibly optimising because it did like to do fun things like normalising constants in earlier revisions...

 

[duffer]

Is that because the hardware and software is there now for R300? Surely for developers NV30 isnt as far away as is it is for consumers.

No, it's not because the NV30 is late or not. It's because the additional features of the NV30 aren't compelling enough to spend the extra time to support.

I would say the same thing even if the NV30 and 9700 were out at the same time.

I think many developers will consider the 9700's features "good enough", and will limit their DX9-specific work to the features of the 9700. The NV30 is better, but probably not better enough to be worth developing for. (Since all the 9700 code will work fine on the NV30 as well.)

Now, if the NV30 turns out to be faster or cheaper than the 9700, then it may still sell more. I'm just suggesting that even if it sells more, its extra features won't be used much.

...and so developers might as well just get started now using 9700, rather than waiting for the NV30. Of course, there's nothing wrong with using an NV30 instead, if NVIDIA happens to give you one.

Regarding: cg is a vendor-dependent non-optimizing HLSL. Good one! But cg is also a way of using HLSL with OpenGL. So there's a possible role for it there.

 

[MDolenc]

You missed the point in the very beginning of this thread... The only thing that's public about DX9 is DX9 RC0 runtime.

 

[duffer]

Oops. Pretend I didn't post this yet, then.

Still, from all the GDC talk slides and drivers and demos that are showing up. I can only assume that the SDK will be made available publicly sometime soon.

 

[MDolenc]

Where are any GDC slides about DX9 (where can I download them )? ATI released their DX9 drivers and DX9 demos because RC0 was made public.
Final DX9 will be made public when it's ready.

 

[Simon Templar]

MDolenc,

http://216.180.225.194/~beyond3d/forum/viewtopic.php?t=3143

While nothing is there yet (or broken), It looks like they intend to post the slides.

-Simon T