[trinibwoy]

Originally Posted by Eronarn

And to the above poster, they're not evil because they're using it. I consider it evil that they're screwing over 99.999% of customers to hype a new product that's actually an old product with a different name.

Please explain who the 99.9% are and exactly how they are being screwed. I'm quite sure Far Cry will continue to run fine on all hardware that it runs on now. What does a non-NV4X/Far Cry owner lose by Crytek's add-ons?

Do you mean that developers have some obligation to support a certain installed base of hardware for any new features they decide to add to an already complete game? By not doing so aren't they merely hurting their own sales?

Quick poll. Will you be happier if

a) the SM3.0 add-ons prove to be worthless and actually slow performance on NV4X.
b) the SM3.0 add-ons are great but someone finds a way to replace the SM3.0 shaders with equivalent SM2.0 shaders and everyone can join in the fun.

[AlStrong]

hm... well most of that 99.9% really consist of the GF4MX people, and I don't think it matters to those people as much either.

It screws the 5xxx or R3xx/4xx people in that they will be forced to buy SM3.0 capable cards just to see shader effects that could have been done using SM2.0 (should they even care, mind you). This is assuming there is no "someone" to automagically convert SM3.0 shaders to SM2.0 shaders.

Option b) is probably what everyone wants, ideally. It's the "replacing with SM2.0 code" that is up in the air right now, unless you're going to do it.

[Evildeus]

Originally Posted by Humus

Wow, quite some response to this thread.

Yeah, first i thought it was on topic then i went

I'm interested too. The demo is fairly simple. It should be easy for someone to just comment out the early-out code, and do some changes to the lighting shader to take advantage of ps3.0.

That's the only thing that would be interesting (apart from the pretty good boost you have )

[Heathen]

Well all I've got to say is, way to go Humus.

One thing (about the demo now ) is that some of the back walls in the demo look REALLY flat. Otherwise stunning.

[Pete]

Now that I've seen the huge gains nV reaped with SM3.0 in FC v1.2 in AT's benches, I'm going to have to reread Humus' original posts on this technique.

[Blastman]

Originally Posted by The Baron

Far Cry 1.2 contains no PS3.0-specific effects, only performance benefits resulting from the use of PS3.0. And even with that, you need a DX9.0c beta installed.

Are you sure about that? If the Farcry SM3.0 patch increases performance 30% -- how much of that performance increase is from actual SM3.0 code -- and not from just a general rewriting/optimizing of the shaders like NV did in Halo? NV could probably get a sizable performance increase by just rewriting the current 2.0 shaders. Marketing department -- hmmmm, that’s a nice increase -- lets market it all as a SM3.0 performance benefit.

[Richard]

Originally Posted by trinibwoy

Also, Nvidia is a corporation that has an opportunity to take advantage of features that are unique to their product and they are doing so. The argument that it is Nvidia's 'fault' that Crytek didn't implement these new features in SM2.0 is infantile. It is actually ATI's 'fault' for not implementing SM3.0 support in the first place. Any sensible person would acknowledge that.

Yes it is possible and feasible, but what incentive does Crytek really have to forego SM3.0 and implement fall backs for SM2.0? ATI sure as hell doesn't seem to be giving them any. So Crytek's decision is $$$+3.0 or nothing+2.0 assuming equal effort for either. Yeah, tough decision.

Sorry, but I really don't agree with this justification. Say ATI pays valve to make all nvidia cards run in fixed-function mode. I'm sure nVidia fans would be extremelly happy by that.

And didn't nVidia fans complain that 3Dmark03 had ATI optimisations (PS 1.4) so much that futuremark had to patch it to include a PS 1.1 fallback? Same thing here. As long as it's reasonably possible to write fallbacks developers should do it. If they don't I'll vote with my wallet. I'm waiting for DOOM 3 before I upgrade. As it stands right now, whether I end up buying a 6800 or X800 I will not be buying FarCry.

Today might be ATI getting the shaft, tomorrow it might be nVidia. And considering xbox2, I don't want a flood of PC titles that screw nVidia fans from 2005-until xbox3.

Humus: keep up the good work. Oh btw, I think FC uses stencil shadows in indoor parts.

[Zeno]

Originally Posted by Humus

That's just one way to show off this technique. It's not limited to this particular application of range-limited lights. It can do any combination of ifs and still do only the same amount of shader work as if ps3.0 dynamic branching would have been used.

You mean the same amount of pixel-shader work, right? Obviously there's more vertex work and additional stencil buffer work.

My biggest question about your technique: Do you need one extra pass (sending of scene to card) per 'if' statement that you wish to emulate, or can you do multiple independent 'ifs' with one pass?

I'm really surprised that there's no performance gain from your idea on NVIDIA cards. It really should be saving some work - a stencil test should come before fragment shading unless (maybe) you modify depth values in your fragment shader? Anyway, I'd like to look into it this weekend if I have time.

[Evildeus]

If i was paranoaic, i would say there's a corelation between the release of the demo and the SM3.0 test @ Anand

More seriously, hope you can do something zeno . I would really like to see the difference between this tech and PS3.0.

[nAo]

Originally Posted by 991060

The performance drop in NV40/NV3x is most likely due to the lack of early stencil kill ability. And I'm not criticising you, Chris, I know you're much better than that.

Weird..I know for sure NV2A performs an early stencil test..so I would expect NV30/40 to have it.
Too bad I own a 9800pro..so I can't test it

ciao,
Marco

[snakejoe]

Originally Posted by nAo

Weird..I know for sure NV2A performs an early stencil test..so I would expect NV30/40 to have it.
Too bad I own a 9800pro..so I can't test it

ciao,
Marco

No, It dosent.
http://www.3dcenter.de/artikel/2003/03-05_english.php

8) In the near future, we will see Doom III and a number of other games based on the new id engine. We already know that that Doom III will highly stress stencil buffers. Does the GeForceFX offer any features increasing performance such as "Fast Stencil Clear", "Early Stencil Test" or a "Hierarchical Stencil Buffer"?

NVIDIA: GeForceFX is very fast at stencil operations, but we are not marketing any stencil-specific implementations.

[Sigma]

This is a demo about what? Of anything is about a stencil hack of a multipass technique to emulate branching of any shader model available on earth (not just PS3.0).

The thing is: it is a stencil hack -> useless. Everyone knows about this, just like eveyone knows for example that a RenderMan shader can be broken down on every hardware with PS1.1 capabilities (not regarding precision of course).

Since the stencil gets used, it is impossible to have stencil shadows on the scene... And what developer would have the trouble of writting a multipass tecnhique using stencil when he could just write an "if". Is like saying that a scene with a single light with PS1.0 supports HDRI: of course it does, it uses one light, so it doesn't overbright...

And haven't you heard? NVIDIA know supports 3Dc. Really, really. It simply doesn't compress the texture. And that means even better quality than ATI, althought I think NVIDIA implementation maybe by slower...

The demo is great, aka Humus style. What I enjoyed is the change in speach, like "Nvidia can consider themselves pwned." when he knows perfecly well that this isn't a replacement for dynamic branching.
Another thing I would like to know Humus is why did you forget to implement any kind of occlusition to the part where it uses branching. That does shift the results a lot because the stencil is the "occlustion"...

EDIT: yah, that is right: I registered just to post this... 8)

[Evildeus]

Welcome Sigma 8)

[Xmas]

Originally Posted by snakejoe

No, It dosent.
http://www.3dcenter.de/artikel/2003/03-05_english.php

Where do you read that? He talks about "not marketing" - which btw has changed in the meantime.

[_arsil]

No, It dosent.
http://www.3dcenter.de/artikel/2003/03-05_english.php

NVIDIA: GeForceFX is very fast at stencil operations, but we are not marketing any stencil-specific implementations.

That only means, that they are not marketing it!

As far as I know, both ATI and Nvidia perform Z and stencil buffer tests before pixel shader. And I observed this behaviour many times writing my own shaders on both cards (NV3x and R3xx). In some situations early tests are impossible, e.g. writing Z value in pixel shaders.


And about technique.. As wrote in far cry ps3 and stuff topic:
- It requiress as many passes as there are paths in the shader
- It doesn't work with transparent triangles and some blending modes
- It wastes cycles in many cases because some computations must be duplicated in every path.

[Mariner]

Originally Posted by radar1200gs

On ATi hardware When you use dynamic branching without the optimisations/bypasses you get a low framerate. When you bypass the branching with what humus wrote it speeds up. Conclusion - Something is wrong with ATi's dynamic branching at the driver or hardware level.

On nVidia when you use dynamic branching without the optimizations it is faster than when the optimization is enabled. In other words the hardware is already efficient at dynamic branching.

Dynamic branching is part of SM3.0 and is therefore not supported by current ATI chips. Therefore, I can't quite see how "Something is wrong with ATi's dynamic branching at the driver or hardware level" :?

The whole point of this thread is to discuss Humus' demo which allows cards that don't support dynamic branching (such as R3XX, R4XX, NV3X etc.) to access some of its benefits.

[samker]

Originally Posted by Evildeus

If i was paranoaic, i would say there's a corelation between the release of the demo and the SM3.0 test @ Anand

More seriously, hope you can do something zeno . I would really like to see the difference between this tech and PS3.0.

Well, this "dynamic branching" demo is about nothing else than stealing the show to nvidia like Humus already stated because it isn't dynamic branching at all. It's just a method which does a different job but nevertheless gives the same result as dynamic branching for some rare lighting situations without the flexbility of what PS3.0 has to offer. But contrary to SM3.0, "Humus new technique" will not be used in any upcoming game.

Unfortunately for Humus, nvidia is currently stealing the show to his fake dynamic branching demo with the upcoming FarCry 1.2 patch (previewed at anandtech and techreport) which includes major performance increases with the help of the SM3.0 path in a real-world game and not in a limited tech demo with some random lights swirling around in a small room.

and yes, you've guessed it, I only registered to post this... but you can expect more

Humus, I must really say that I am deceived of you and the way you're spreading misinformation around different forums. You really should know better.

[Evildeus]

Well, welcome here, thanks for the explanation and post more

[HAL-10K]

He is using a programming trick to do in this specific shader something that has similar results like dynamic branching.

But this does not show that dynamic branching "is just a marketing thing".

It is impossible to do effective dynamic branching in most shader programms with SM2.0!

[Dave Baumann]

Originally Posted by samker

and yes, you've guessed it, I only registered to post this... but you can expect more

Please, feel free to discuss the technical merits / drawbacks of various solutions.

[SvP]

Quite a number of people seem to be personally offended by this piece of code

[AlStrong]

"nVidia can consider themselves owned "


sounds more like a joke to me, especially with the smilie there.

[trinibwoy]

Originally Posted by Mordenkainen

Sorry, but I really don't agree with this justification. Say ATI pays valve to make all nvidia cards run in fixed-function mode. I'm sure nVidia fans would be extremelly happy by that.

I'm not really trying to justify anything. And your analogy is poor at best Far Cry does support the highest shader model available on ATI cards - 2.0. Running a 2.0 card at 1.1 is in no way analogous to this situation.

And didn't nVidia fans complain that 3Dmark03 had ATI optimisations (PS 1.4) so much that futuremark had to patch it to include a PS 1.1 fallback?

Similar situation, wrong application. I don't think you can equate a benchmark to these extra Far Cry features. Please realize that these features are in a patch and are not what you 'paid for' so to speak. If you though Far Cry was awesome before and willing to buy it, why would you change your mind now? The game hasn't.

[Evildeus]

Originally Posted by Alstrong

"nVidia can consider themselves owned "


sounds more like a joke to me, especially with the smilie there.

You may be right, but it seems to me that the reason of the is to try to demonstre the non-advantage of PS_3.0 branching (and hence Nv40) and it seems that many people (and even new ones) are displeased with this way and even more disagree with the advantages of this particular technic.

Unfortunately the discussion over this technic is a bit difficult as the times of posting are quite incompatible.

[pat777]

Sorry, but I really don't agree with this justification. Say ATI pays valve to make all nvidia cards run in fixed-function mode. I'm sure nVidia fans would be extremelly happy by that.

You could always force the SM 2.0 path if that happens. NV40 can do everything any version of SM 2.0 can do without code change.