Digital Foundry Article Technical Discussion Archive [2011]

[Barso]

The most interesting thing for me in this article is the triangles graph in this autobot image; which unless I'm reading it wrong suggests that the finished version of KZ3(Jan 2011) is processing 1312.655 Million triangles per second between the RSX & SPU software renderer GG mentioned.

1312.655 (graph shows numbers in millions) = Primes 227 + Geometry 271.396 + Shadow 748.846 + Forward + 15.413 + Occluding 50

That information if understood correctly? would refute the long held view of DF that the Playstation 3 is inferior to the 360's (500M Xenos + 2 General PPU cores) to render geometry. PPUs are not a good fit for software rendering.

The graph also suggests that Killzone 3 is using a 3 separate frustum passes just for shadowing, and probably implementing a 3 cascade shadow map system (3x geometry ~= shadows). This in itself is very impressive considering it is rendering at a full 720p with 3km draw distance(32bit depth most like needed) & theimplementation of MLAA & HDR.

 

[betan]

The thing is that that particular scene may use 80% of resources as shown but other one may take all,maybe even go overboard.There is no point in upping the graphics in a bit less chaotic scenes and lowering them in one that are more chaotic.They could add a bit more things so you get to almost 100% in this particular scene but others that are even more taxing would suffer in frame rate.

EDIT.
Joker beat me to it

There is a valid case for dynamic scaling of resolution (or AA for some). See Wipeout HD

 

[(((interference)))]

This doesn't seem to tie in with responses to my questions about whether the PS3 can push more geometry than the 360 can.
http://forum.beyond3d.com/showthread.php?t=59426&page=12

The responses I got were that the 360 can push 2x as many polys as the PS3 and that it was mainly good art and level design on the PS3 side of things.

So is that still true when the SPUs are used for culling?

 

[Ruskie]

This doesn't seem to tie in with responses to my questions about whether the PS3 can push more geometry than the 360 can.
http://forum.beyond3d.com/showthread.php?t=59426&page=12

The responses I got were that the 360 can push 2x as many polys as the PS3 and that it was mainly good art and level design on the PS3 side of things.

So is that still true when the SPUs are used for culling?

In theory Xenos outperforms RSX by some margin,according to Joker,in real life also.The thing is,SPUs don't put triangles on screen,they send culled to RSX so it doesn't have to render those that are not visible.

It would be really nice if Joker could once again shed some light on the subject since its gone 5 years since his famous thread about RSX being Vertex limited.I would say,since Xenos is unified gpu,that it still should have easier time pushing triangles on screen,as we have seen in alot of games this gen.Load from pixel shading and vertex shading changes from scene to scene and it will ultimately be easier for Xenos to handle it .Lots of developers(if not all) use SPUs for triangle culling so that could give you more insight.

 

[ultragpu]

The most interesting thing for me in this article is the triangles graph in this autobot image; which unless I'm reading it wrong suggests that the finished version of KZ3(Jan 2011) is processing 1312.655 Million triangles per second between the RSX & SPU software renderer GG mentioned.

I don't think that number represents what's displayed on screen per second, they said they're rendering 3x more polys than killzone 2 so in reality it should be closer to 4million polygons per frame since kz2 was doing well over 1million polys. Of course I'm only speculating according to what GG said, would any tech masters elaborate this further?

 

[Arwin]

To put it simple:

Most people here believe that the RSX is weaker than Xenos when it comes to pushing geometry. RSX can be quite capable and even outperform Xenos given the right combination of shading and geometry, but Xenos is more flexible so there are more combinations where Xenos will beat RSX. Digital Foundry isn't saying anything else.

The RSX needs the Cell processor to alleviate that bottleneck. The question that remains is if Cell + RSX is a more powerful combination than Xenon + Xenos. Exclusives suggest that answer could and should be yes, but others suggest the games just look better because of better art, or because Microsoft and its studios just don't push the hardware as much.

Imho, It's not nearly as interesting to discuss which console has the bigger ... as it is to admire the technological breakdown and behind the scenes looks that rare interviews and screenshots like these afford us.

 

[Nesh]

Well whatever the case, the PS3 gets the best blend of hardware use and art so far, which its what that matters at the end.
I have experienced some truly amazing and impressive games form my 360, but it still misses the level of WOW factor I got from those few PS3 titles. I think they got the immersion better than anyone on the PS3. I am very confident though that Gears 3 will be that game.

 

[joker454]

It would be really nice if Joker could once again shed some light on the subject since its gone 5 years since his famous thread about RSX being Vertex limited.

Lol, has it really been 5 years? Goodness how time flies. I mean I could post an answer but it's complicated, would take some time to type up, and I would have to defend it for the next four weeks. I'm just too tired for that. I'm semi retired now anyways and in a, uhh, entirely different line of work. Someone else needs to step up, post, and take the inevitable forum abuse that follows. I'd be happy to pass the charlatan torch to them, any takers?

 

[(((interference)))]

See, I was wondering as KZ looks to be pushing more geometry than Halo Reach (which itself apparently pushes 4 million more polygons than H3)

But then is it just good art? Theoretically the 360 should have an advantage in most graphical areas (besides things like post processing) due to the unified shaders, eDRAM, loads of bandwidth and more available RAM, correct?

This is borne out by the AAA multiplat titles, but then of course the argument turns to those engines not being designed optimally for PS3 (even Cryengine 3), so do we have to wait for (BF3 which has large scale utilisation of the SPUs) to see if this isn't true?

I suppose we could approach it from the other end as well, take a PS3 exclusive like Uncharted 2 and say it was built as a 360 exclusive instead, what differences should we expect to see from the PS3 title? eg. lower quality DoF, motion blur, full res transparencies, higher polycounts, higher texture detail etc?

 

[Barso]

I have no doubts that uncharted 2 would look better on the 360 if done right.
The only problem is that Microsoft has a different focus at the moment regards the xbox360.
I can't help but feel we will never find out what the xbox360 is really capable of if it's pushed as much as the PS3 is with their first party titles.

 

[SteelOak]

KZ looks to be pushing more geometry than Halo Reach

really ?
I have no idea but I'm just curious.
I thought that models and this big environments in Reach are pushing lots of polys.
I don't care about KZ comparisons but do we know how much polys Reach pushes ?

This is borne out by the AAA multiplat titles, but then of course the argument turns to those engines not being designed optimally for PS3 (even Cryengine 3), so do we have to wait for (BF3 which has large scale utilisation of the SPUs) to see if this isn't true?

I don't think I understand you correctly,waiting for engine that takes advantages of ps3 spu's in order to tell what platform is "better" ?

 

[(((interference)))]

really ?
I have no idea but I'm just curious.
I thought that models and this big environments in Reach are pushing lots of polys.
I don't care about KZ comparisons but do we know how much polys Reach pushes ?



I don't think I understand you correctly,waiting for engine that takes advantages of ps3 spu's in order to tell what platform is "better" ?

Yes, Reach has huge environments, but they don't tend to be very detailed and the geometry of the buildings and environments tends to be rather simple.

We don't know how many polygons their pushing, but its apparently 4x as much as Halo 3 or 4 million more polygons overally than 3
http://www.joystiq.com/2010/02/11/x10-halo-reach-demoed-will-be-the-definitive-halo/

I meant that with BF3 we'd get a MP engine that no one could argue was a 'lazy port' to PS3 (which usually gets levelled at MP titles where there is a disparity between the consoles eg RDR, GTA4, Black Ops) and so if the 360 version still outperformed it we could say that it's mostly talented devs, smart tech and great art rather than raw performance that gives PS3 titles their edge.

 

[MJP]

Did Guerilla ever say that? I don't doubt it's true, makes sense that they would do it like that, but I'm curious if they ever confirmed that someplace. Now that they have an spu software rasterizer they could potentially use it for a full resolution transparency pass. Assuming there was spu time to spare of course which KZ3 doesn't, but maybe other games could do it.

They did, in a GDC presentation that I attended. They actually started at full 1280x720 when they implemented the new system, and late in production they switched it down to quarter-res.

The slides from the presentation are up now, if you want to have a read:

PDF (15MB)

PPT (150MB)

 

[AlNom]

I don't think that number represents what's displayed on screen per second,

These are frame captures.

they said they're rendering 3x more polys than killzone 2 so in reality it should be closer to 4million polygons per frame since kz2 was doing well over 1million polys.

Too vague a reference. It's PR, so it could be anything (culled/not culled, visible/not visible).

The total figure you see here is what's rendered.

Yes, Reach has huge environments, but they don't tend to be very detailed and the geometry of the buildings and environments tends to be rather simple.

There are so many things wrong with this statement.

*sigh* Why does it always come back to platform pissing contests. :/ It's so off-topic.

 

[SteelOak]

I meant that with BF3 we'd get a MP engine that no one could argue was a 'lazy port' to PS3 (which usually gets levelled at MP titles where there is a disparity between the consoles eg RDR, GTA4, Black Ops) and so if the 360 version still outperformed it we could say that it's mostly talented devs, smart tech and great art rather than raw performance that gives PS3 titles their edge.

I know but for me Battlefield 3 example proves nothing just like RDR example,different engines ,different developers.
I dont' know how we can tell that RDR or any different game is just bad port and B3 will be definitive example that proves something.
Maybe I don't know enought about this Frostbite 2.0.Is it first proper multiplatform engine that takes advantage of every positive aspects from both consoles ?
After 6 years we still don't know which platform is "more capable" and amount of time which is needed to find it out tell's me that difference is to small to care.
Why people can't just appreciate what developers do on these old weak consoles

sorry for english,still learning

 

[patsu]

Interesting article for people who like interesting things

Digital Foundry : The Making of Killzone 3

http://www.eurogamer.net/articles/digitalfoundry-the-making-of-killzone-3

Great work Grandmaster!

They did, in a GDC presentation that I attended. They actually started at full 1280x720 when they implemented the new system, and late in production they switched it down to quarter-res.

The slides from the presentation are up now, if you want to have a read:

PDF (15MB)

PPT (150MB)

Cool, some more advancement for parallel CPU + GPU rendering. ^_^

Glad to read that Edge is still getting used. Those tech sharing definitely paid off.

They plan to move even more stuff from the PPU to the SPUs. Wondering what the PPU will be used for in the end. ;-)

 

[patsu]

Just teasing. I don't think 150% really correlates to power. It's hard to read what they actually mean by the graph, but I believe 100% is indeed 33ms. If that's true, then the CPU tasks were limiting framerate up until the end (for that particular snapshot) where they seem to have gotten things more or less sync'd with the GPU. But that's just my interpretation of the graphs for the moment. In the end, it's still a snapshot, and there's going to be a whole game to consider. Targeting 100% of 33ms is a bad idea if one wants a stable 30fps regardless of what can happen. They need some head-room afterall.

Early day numbers may be based on part KZ2 and early KZ3 subsystems, until they redid individual components. Once everything is running, then they probably optimize the code and levels to make sure everything is below the line.

GG mentioned they found 50% extra resources since KZ2. It is said that they measured an old KZ2 level on the new engine.

 

[Lucid_Dreamer]

I have no doubts that uncharted 2 would look better on the 360 if done right.
The only problem is that Microsoft has a different focus at the moment regards the xbox360.
I can't help but feel we will never find out what the xbox360 is really capable of if it's pushed as much as the PS3 is with their first party titles.

The whole "360 is not being pushed hard" theory has been debunked. Halo: Reach, among other games, has proved that. They're even using tesselation on the 360. When the devs did the DF interview, all these things were abundantly clear. There is nothing like a nebulous theoretical/potential performance pipe dream.

I would like to see more than Sony 1st party studios being open with what they are doing/achieving on these systems. Show the SPU and GPU usage and what it's being used for. In my experience, the more open you are; the more honest you're trying to be.

Personally, if the interviewer knows that some people like to brush certain information off with "that screenshots mean nothing" or "it's just art" type statements; I think the interviewer should ask for all the details (without breaking NDA of course).

I loved the tech based article and I hope Grandmaster can take some of these question/statement posts to GG, as a tech follow-up. A clarification article for the technically inclined. Is this even possible?

 

[Tap In]

The whole "360 is not being pushed hard" theory has been debunked. Halo: Reach, among other games, has proved that.

If Reach looked exactly as it does yet were designed as a tightly controlled corridor SP experience with set pieces and relatively few enemies instead of what it is (with resources assigned to much more than that), than yes, you would have a point that it's been "proven".

 

[joker454]

The whole "360 is not being pushed hard" theory has been debunked.

Both machines are being pushed really hard at this point.

They did, in a GDC presentation that I attended. They actually started at full 1280x720 when they implemented the new system, and late in production they switched it down to quarter-res.

The slides from the presentation are up now, if you want to have a read:

PDF (15MB)

PPT (150MB)

Cool, thx for that. Judging from their numbers it looks like mlaa and their spu occlusion are taking the lions share of all spu time. The "checked it in quietly" comment in the slide made me laugh, been there done that