PS3 GPU not fast enough.. yet?

[Mintmaster]

The reason I'm 'ignoring' the XDR access from RSX is that I thought it had been agreed that the latency is way too high for you to use it for a sustained bandwidth-intensive purpose like texturing?

Texturing is not really "sustained bandwidth-intensive" really, especially for compressed textures. XDR texturing will be used and I believe it will help performance, but not by a huge margin, and not all the time. The bigger issue is finding room for your textures in XDR.

Latency is high, but sometimes your pixel shader is more amenable to texture latency (esp. when it has only a few registers). It would be harder to use it for the Z or colour buffer while not degrading performance.

I don't see a problem with 'texture resolution' in PS3 games either, for that matter.

I agree with you, Titanio. predicate, I think it's a case of seeing things you want to see. I remember hearing people saying PS3 will have more geometry and XB360 will have more textures. I don't see why this discrepancy would exist.

 

[predicate]

Texturing is not really "sustained bandwidth-intensive" really, especially for compressed textures. XDR texturing will be used and I believe it will help performance, but not by a huge margin, and not all the time. The bigger issue is finding room for your textures in XDR.

Latency is high, but sometimes your pixel shader is more amenable to texture latency (esp. when it has only a few registers). It would be harder to use it for the Z or colour buffer while not degrading performance.

Oh OK then, I'm regurgitating mis-read information in that regard then

I agree with you, Titanio. predicate, I think it's a case of seeing things you want to see. I remember hearing people saying PS3 will have more geometry and XB360 will have more textures. I don't see why this discrepancy would exist.

Bleh, I'm seeing a difference. And it's not really what I want to see either, because I'm getting a PS3 (damn my uncontrollable Kojima whoring!)

 

[London Geezer]

Oh OK then, I'm regurgitating mis-read information in that regard then


Bleh, I'm seeing a difference. And it's not really what I want to see either, because I'm getting a PS3 (damn my uncontrollable Kojima whoring!)

The problem is that you're comparing a finished game (Kameo) to "things you saw on the net" which are far from being completed. Besides, it really is down to the artists and developers. Kameo has great surface detail, but it's hardly because of extremely ultra high-res textures, it's more because of very clever use of wonderful pixel shading features like normals, parallax mapping, and a whole other list of features which make surfaces look awesome. That's really mostly the responsibility of the artists and developers that have to design and integrate all those features in the game.
I really don't see why the RSX should have any technical problems in replicating all those features. The problem is finding artists who will do all that work, and i'm sure we will see it eventually.

Mentioning MGS4 is a bit flawed, as obviously the team's design priorities are very different from the priorities the Kameo team had. The most glaring example is that Snake's head has apparently 60,000 polygons just for itself, which is probably 10 times the total polygon count for Kameo's main models. As i said, different design choices.

 

[Shifty Geezer]

Bleh, I'm seeing a difference. And it's not really what I want to see either, because I'm getting a PS3 (damn my uncontrollable Kojima whoring!)

I think your overlooking the software side of things. The lack of highres textures doesn't mean the hardware isn't capable of better; it doesn't tell you where the limit is. Screens of UT2007 for PS3 on IGN using the same engine as GOW by the same company as GOW has the same high level of detail as GOW. Likewise you can look at some games on XB360 like PDZ N3 and conclude the hardware isn't capable of better - wrongly. So until we see a glut of titles of which none have that fidelity, conclusions as to hardware capabilties are premature.

 

[nAo]

How big can this fifo be? A 20K model would easily run hundreds of polys consecutively that are culled,

it depends, you can lay down an index buffer smarter than that..

AFAIK, the post transform cache is 63 verts max on RSX.

dunno

What is there to set up exactly?

http://www.cs.unc.edu/~olano/papers/2dh-tri/2dh-tri.pdf
(page 7, bottom left..)

Pffft. You suck.

you wish

 

[predicate]

I think your overlooking the software side of things. The lack of highres textures doesn't mean the hardware isn't capable of better; it doesn't tell you where the limit is. Screens of UT2007 for PS3 on IGN using the same engine as GOW by the same company as GOW has the same high level of detail as GOW. Likewise you can look at some games on XB360 like PDZ N3 and conclude the hardware isn't capable of better - wrongly. So until we see a glut of titles of which none have that fidelity, conclusions as to hardware capabilties are premature.

True, when I posted I figured the alternative answer was that it isn't such a priority for PS3 developers, but for none of them to be doing really high resolution textures just seems a bit odd when 360 developers did for launch games and still matched up in other technical areas.

 

[_phil_]

MGS4 don't have low rez textures,that's a rather wrong perception.
http://hardwired.hu/forum/forum.phtml?area=comment&id=18030

 

[Acert93]

True, but if there were a unified pool, any space the GPU occupies is less space for the rest of the game That's a tradeoff for the developer to make given their own requirements.

It is not just an issue of space, but also of bandwidth. While a split memory pool can be a pain, having 2 256MB pools, each with 22-25GB/s of bandwidth, is better than 1 512MB pool with 22GB/s bandwidth.

The point I think which was being made was that if 1 of the pools (GDDR3)becomes bandwidth saturated with graphical tasks you have in many ways cut down your memory footprint, which means less space for textures. (Of course saturing one memory pool is better than saturating 1 large pool with the same bandwidth).

In such a scenario there are work arounds (e.g. if relying heavily on XDR texturing you could use GDDR3 as a fast cache, it would not be much bandwidth to move/swap the 200MB of texture/vertex space on the GDDR3 to the XDR a couple times a frame if necessary) but it does mean more work and some tradeoffs.

I don't see a problem with 'texture resolution' in PS3 games either, for that matter.

I have not seen a lack of texture resolution in PS3 games in general (hard to make such judgements on unreleased hardware), but I think the problem is pretty transparent on the development side and could be a problem for the non-elite developers (who don't have the resources a 1st party or large 3rd party have) and cross platform titles. Both consoles have problems developers need to address to get the most out of the platform, all overcomable to various degrees. Balancing memory for bandwidth and storage and maximizing your memory utilization is an issue a lot of developers will face, especially those with PC backgrounds. You know, because PC devs are spoiled

 

[Laa-Yosh]

C compared with the texture detail of the background of this shot of Gears of War.

You're a bit biased, choosing an offline rendered shot of GOW that has better AA and filtering than the MGS one... and who knows about it's textures. But it certainly is not an ingame screenshot.

 

[Laa-Yosh]

The reason I'm 'ignoring' the XDR access from RSX is that I thought it had been agreed that the latency is way too high for you to use it for a sustained bandwidth-intensive purpose like texturing?

The reason why developers won't ignore it is that there's just not enough room left in the 256MB GDDR memory when they're using multiple HD resolution render targets, especially with HDR and/or antialiasing. They have to make it work somehow, and I'm sure they will.

 

[Inane_Dork]

It is not just an issue of space, but also of bandwidth. While a split memory pool can be a pain, having 2 256MB pools, each with 22-25GB/s of bandwidth, is better than 1 512MB pool with 22GB/s bandwidth.

If the pools were used for the same thing, yeah. But they're not, so we're back to not knowing for sure where the advantage lies.

Games have CPU code and GPU code which both have memory latency, bandwidth and size demands. That's plenty to muddle the issue. Move texturing to XDR? Well, there's only 192 MB of XDR that's usable to the game and you stand to reduce RAM efficiency with the added processes reading from it. The latency might be great enough to slow down rendering, too. But you may not have another choice if the GDDR3 is already sapped each frame because of bandwidth or size. And, of course, it might be possible to partially texture out of XDR, so then you have to figure out which textures to put there.

Yada yada. I haven't even gotten into the ratio of math ops to texture ops in pixel shaders or how this compares to the X360. With all these considerations, surely the only truly useful benchmark is the one you get from your game. Maybe the coming years will grant a rule of thumb, though.

I have not seen a lack of texture resolution in PS3 games in general (hard to make such judgements on unreleased hardware)...

Given that dev PS3's have up to 2x more RAM than consumer PS3's, I think that's pretty accurate.

 

[Laa-Yosh]

Yada yada.

So, that's why I think that the PS3 is a very powerful and flexible console - but at the same time it's unnecessarily complex which in turn leads to oversized programmer teams, huge budgets and long development time.

Before the devs here start to write their responses, please think again: it might be a good challenge, lots of fun and so on - but what's your budget, how long are you going to work on your game, how lucky you are to be able to do this? Couldn't you do more if the hardware was more straightforward? Couldn't more studios develop better games?

 

[Nemo80]

Given that dev PS3's have up to 2x more RAM than consumer PS3's, I think that's pretty accurate.

Afaik the final devkits don't have that anymore. But do you really think that texture resolution is now higher because games run on devkits? Sorry, but that's utter bs.

 

[scooby_dooby]

you wish

Ohh...damn...nAo pulls out the grade-school burn!

 

[slider]

So, that's why I think that the PS3 is a very powerful and flexible console - but at the same time it's unnecessarily complex which in turn leads to oversized programmer teams, huge budgets and long development time.

Before the devs here start to write their responses, please think again: it might be a good challenge, lots of fun and so on - but what's your budget, how long are you going to work on your game, how lucky you are to be able to do this? Couldn't you do more if the hardware was more straightforward? Couldn't more studios develop better games?

That's the sort of thing that needs a "how much more difficult/time-consuming (if indeed it is) is it?" answer. But imagine the s***-storm that'd create...

 

[Tap In]

That's the sort of thing that needs a "how much more difficult/time-consuming (if indeed it is) is it?" answer. But imagine the s***-storm that'd create...

not on this board .... on this board we can learn things, this isn't one of 'those' boards where people throw *stuff* around... well they're not here for long if they do.

 

[predicate]

You're a bit biased, choosing an offline rendered shot of GOW that has better AA and filtering than the MGS one... and who knows about it's textures. But it certainly is not an ingame screenshot.

All the released MGS4 shots are devshots with upped AA and filtering aswell. The textures just aren't that high detail.

 

[Acert93]

All the released MGS4 shots are devshots with upped AA and filtering aswell. The textures just aren't that high detail.

And you know this how?

 

[predicate]

And you know this how?

Uhhhh, the fact that they've got unrealistic level of AA and AF as well?

 

[chachi]

Afaik the final devkits don't have that anymore. But do you really think that texture resolution is now higher because games run on devkits? Sorry, but that's utter bs.

All devkits for any console have more RAM than the consumer version because they have to run code that isn't optimized and contains debugging information that the consumer code doesn't have.

Does that mean that developers are going to use the extra RAM for added texture detail? They *could*, yeah, but eventually they're going to have to fit into the consumer console constraints and it doesn't make sense to tune your game to run on something like a developer console. I won't say it hasn't happened though because obviously developers have done more mendacious things to create a good impression of their games (e.g. target renders presented as real-time footage).