*Game Development Issues*

[Terarrim]

But it seems as if nAo is doing RSX work rather than Cell in the example given. Given that the RSX is nowhere near as complicated (or new) as the Cell it baffles me that mp devs are having such a hard time and that the team were using the RSX so badly (or coding so badly) before nAo leant his expertease.

It would also seem to add weight to many of the discussions that nAo has had with Jester regarding the RSX (I believe they agreed to disagree finaly). And nAo seems to be infering that the fixes were not to time consuming and optimisations could be taking place to get even better performance.

 

[Laa-Yosh]

It's nothing personal, but... what makes you trust one developer over the other?

 

[Titanio]

If this is a catch-all thread for commentary from developers, this might be a relevant one (from an Edge preview of Conflict: Denied Ops on PS3/360);

I think we've been quite surprised by PS3. It may be because we've done five PS2 games, and so are very familiar with the Sony tools and SN System tools. While we've struggled along like everyone else to make sure that we're throwing the right amount of work to the PS3's SPUs, we've had to that on 360 too; I wouldn't say we've found the PS3 any more difficult, and our guys who are on it genuinely enjoy working on the platform. I think there's just been some unwarranted negative commentary, and it's just a case of really putting the effort in.

As for trusting developers, I think there's two kinds of thread going on here..

..if discussing what a system is capable of or what is possible on a system, then point-blank, I'd trust those who've demonstrated the best results, whoever they may be (first, third party, whatever)

..if discussing how easy it is to meet goals within certain constraints (time, budget), one has to listen to a wider pool of developers... but if given a similar set of constraints, one developer produces better results on a system than another, I'd be more inclined to trust the opinion of the former. I don't think we should let political correctness stand in the way here - if one developer in a given set of circumstances gets better results than another in the same or similar circumstances, the former are clearly doing something right and the latter are clearly doing something wrong.

And I do think it is fair to point out competence and experience as a big variable here. Sure, time and budget are also big factors at play here, but I don't think its controversial to suggest that some of the problems encountered by some of the developers working on these systems are rooted in competence and experience issues, as much as other factors. Not all developers are created equally, the label 'developer' doesn't suddenly put you on an equal footing with everyone else bearing the same label. And I don't think it should be shocking if people gravitate toward the opinions of those who demonstrate greater competence or ingenuity, or who have greater experience.

 

[szymku]

I work on a multiplatform title, when I joined the company Xenos was outperforming RSX on vertex shading by a vast margin, especially in simple color passes (zprepass, shadow maps).
Now (in those rendering passes) RSX is slightly faster than Xenos on average, with no SPU intervention, and I know it could be even faster (better performance were simulated through experiments on recorded push buffers) using memory in a different way.
Both platform shares EXACTLY the same high level shader code, Xenos wins when artists forget to check in some LODs and we render distant meshes with some insane triangle count, lots geometry that hardly generates any pixel and RSX gets vertex shader limited.

I assume that you are working in Lucas Arts.... So I think I can guess which title you are working on :smile:

 

[betan]

I assume that you are working in Lucas Arts.... So I think I can guess which title you are working on :smile:

Lego Indiana Johns?

Seriously if I had to pick one multiplatform game to have a decent PS3 port, that would be the new Jedi game.

 

[archangelmorph]

I assume that you are working in Lucas Arts.... So I think I can guess which title you are working on :smile:

Fracture..?
Force Unleased..?
Indiana Jones..?
Free Radical Project..?

Not necessarily! It's like the obsolete art of assembly coding. Ok, that may offend a few here But the reality is that for the most part, given the complexity of todays hardware you are better off coding in a slightly more abstracted language and just let the compiler arrange the microcode optimally for you. Overall it's likely to do a better job. That's why for example it's always strongly recommended to write shaders in hlsl and just let the compiler do the rest.

In this case, the gpu ultimately has intimate knowledge of whats going on at any given moment and is in a better position to determine what load needs to be distributed where at a given frame. We can try to help it a bit on our side, but only at a more macro level. We are better off letting Xenos do it's thing.

Is this generally true for all platforms?

Are you familiar with Intrinsics & have they provided any peformance gains for you in any areas? (Also does the 360 have anything like this?)

I'm curious because especially in the area of something like using SPUs for physics or graphics-related tasks, I'd assume that there could be some benefits to their use in optimisation to some degree..?

(NOTE - I've done a bit of work using both intrinsics & vFPU assembly on the PSP but in the end didn't get any major perf gains.. & Our PS3 team barely use the SPUs at all due to the reduced scope of the project so my knowledge & experience in the areas of PS3 development is.. to put it politely.. progressing.. )

 

[pipo]

Now (in those rendering passes) RSX is slightly faster than Xenos on average, with no SPU intervention, and I know it could be even faster...

<snip>

Both platform shares EXACTLY the same high level shader code, Xenos wins when artists forget to check in some LODs and we render distant meshes with some insane triangle count, lots geometry that hardly generates any pixel and RSX gets vertex shader limited.

In other words, the 360 could be pushed harder too... But that's the kind of trade off you will always see on multi-platform titles.

You're in there for your PS3 ninja skills I suppose?

 

[pipo]

If this is a catch-all thread for commentary from developers...

Another one: http://www.gamesindustry.biz/content_page.php?aid=30375

He told the BMO Capital Markets conference yesterday that the two next-generation machines were "close in what we can do with them" and that while the PS3 has some elements that are better, the Xbox 360 has other advantages.

...

Additionally he explained that in Ubisoft's experience, translating a game from the Xbox 360 platform to the PS3 took no extra effort than doing it the other way around.

"What we do now is create for the PS3 and 360 at the same time, and it doesn't cost more than 10 per cent extra to develop for the other machine.

"Before it was costing us more, about 20 per cent, just because it was difficult to learn the PS3 hardware, but now our engines are done and we can easily develop for both machines."

 

[fireshot]

The way devs speak about Xenos make it sounds like RSX is a poor GPU in relation to it. How can this be? The RSX is a close cousin of 7800GTX, which was quite a performer in its days, and if ATI have such a winning GPU design, why are they still sniffing Nvidia's dust today?

 

[Dr. Nick]

In other words, the 360 could be pushed harder too...

That is what I was thinking too or are we mistaken. If the Xenos can waste resources on the example that nAo gave couldn't a Dev allocate geometry elsewhere when a proper LOD system is put in place. I'm not sure if I understood Joker's answer to my question but I thought using LOD's would help performance on both systems. Does the 360 have some problems using them? In what cases would the Xenos become vertex limited?

Also I have a hard time believing that ATI got Load Balancing perfect the first time around. So could someone in the know hint at if there have or have not been updates to their Load Balancing algorithm or am I just mistaken?

The way devs speak about Xenos make it sounds like RSX is a poor GPU in relation to it. How can this be? The RSX is a close cousin of 7800GTX, which was quite a performer in its days, and if ATI have such a winning GPU design, why are they still sniffing Nvidia's dust today?

The one thing about the G70 that always got me is that it was pretty much designed to run mostly games that were already out on the market pretty fast. Nvidia didn't really seem to be forward looking when they made the GPU because they released the G80 a year later and that seemed to be the real next step up in comparison the the G70 and previous generations of cards.

 

[Terarrim]

In other words, the 360 could be pushed harder too... But that's the kind of trade off you will always see on multi-platform titles.

You're in there for your PS3 ninja skills I suppose?

But this does fly in the face of what Joker was saying (regarding RSX being the weak point of the PS3). I would be intrested to learn how long it has taken nAo to get the performance he was talking about. I.E. was it ninja skills neaded or a yellow belt in karate lol.

 

[archangelmorph]

In other words, the 360 could be pushed harder too... But that's the kind of trade off you will always see on multi-platform titles.

You're in there for your PS3 ninja skills I suppose?

How did you get that?

Now (in those rendering passes) RSX is slightly faster than Xenos on average, with no SPU intervention, and I know it could be even faster...

This statement states pretty clearly that RSX has the edge on average.. (I know joker454 mentioned something about shader code so i'd be interested in finding out the differences between the size/complexities of the shaders both nAo & joker's teams are running..)

Both platform shares EXACTLY the same high level shader code, Xenos wins when artists forget to check in some LODs and we render distant meshes with some insane triangle count, lots geometry that hardly generates any pixel and RSX gets vertex shader limited.

& this statement says nothing more than the fact that RSX isn't as great a performer on unoptimised art..

However he already said that on average (when art is properly optimised as intended for both platforms) both platforms are evenly matched (only slightly in favour of RSX) which implies that both Xenos & RSX aren't wasting cycles on housekeeping..

I'm not commenting on the weight of nAo's information nor am I drawing any conclusions from it (at least until I can see what joker has to say in response), but I really don't see how you (pipo) could read his statement and spin it so far out of context/of the stratosphere like that..!?

Do you want to explain your logic in terms of how you came to such a conclusion that that was what nAo was implying?

 

[pipo]

Do you want to explain your logic in terms of how you came to such a conclusion that that was what nAo was implying?

More headroom not being used == could be pushed harder.

By the way: spin & out of context?

Hold your horses...

My 'that's the kind of trade off you will always see on multi-platform titles' works both ways in case you didn't get that.

 

[liolio]

His statement lets also think that xenos performs pretty well even on non optimized code

 

[pipo]

Also I have a hard time believing that ATI got Load Balancing perfect the first time around.

Not very likely (is there such a thing to begin with) but devs can use hints to improve processing AFAIK.

 

[Butta]

His comments seem to say PS3 slightly ahead on pixel shader while 360 deals better with vertex shader bound scenarios... nothing new, and this relates only to video card use without CPU intervention. I wonder how things would be different if we looked at the consoles as a whole? Would there be that much advantage to cell assist in pixel and vertex functions? Enough to visibly show better results?

 

[patsu]

More headroom not being used == could be pushed harder.

He's saying both GPUs still have headroom (Note his comment about RSX can still go faster too). Also this is without SPU assistance.

His statement lets also think that xenos performs pretty well even on non optimized code

Yes... that's exactly it because of unified architecture.


If I remember correctly, nAo usually says, "The RSX is not slower than Xenos". Something about RSX that can help it optimize to the same level ?

 

[Terarrim]

seems to me that the conclusion drawn would be that

Xbox 360 CPU and GPU can cope easier to develope for due to being more forgiving "better" dev platform support.

PS3 Cell and RSX both need more streamlined/optmised code to work properly.

While I understood the CPU side of this, I never realised that the RSX also needed that extra attention although I would imagine that due to the Nvidia legacy this shoudn't be as difficult to work with as the Cell (at least initial development).

The only exceptions to this would be RSX memory managment if the dev team felt that more than just GDDR memory was needed.

 

[pipo]

He's saying both GPUs still have headroom (Note his comment about RSX can still go faster too).

Sure. That's why I said 'could be pushed harder too'.



At the end of the day, I think the differences will be minimal. Exclusive titles will be fantastic for both platforms.

Even MP titles (CoD4 anyone?) are great right now...

 

[liolio]

seems to me that the conclusion drawn would be that

Xbox 360 CPU and GPU can cope easier to develope for due to being more forgiving "better" dev platform support.

PS3 Cell and RSX both need more streamlined/optmised code to work properly.

While I understood the CPU side of this, I never realised that the RSX also needed that extra attention although I would imagine that due to the Nvidia legacy this shoudn't be as difficult to work with as the Cell (at least initial development).

I agree but Nao said nothing about the 360 version.
So we can guess that the 360 run some non optimized code, and to some extends we could conclude that the 360 is not pushed to the max because it's too forgiving, ie standart code run good enough and time/budget constraints won't make thing change in the future...