Digital Foundry Article Technical Discussion Archive [2010]

[Kasersky]

It's a complex answer, but let's just say, the 360 was pushed hard, to a place where the PS3 couldn't go with the old tricks. Most of the time the battle was fitting the game in memory, and often to get performance you need to trade even more memory. I can go into details but with such a high profile title I'll quickly get in trouble.

i'm glad you guys pushed the hardware instead of holding back just for the sake of parity. i always felt that in mw2 there were extra cycles and texture bandwidth that was under utilized simply because it would mean a disparity between the xbox and ps3 versions.

too bad this is not how most people will recognize it instead of pushing one console they will view it as poor porting when its obvious that you guys utilized the spus and even took a look at mlaa.

 

[Boxercide]

I believe all the comparison pieces are done either by grandmaster or...argh. I can't remember the guys handle. But the other guy stopped posting on B3D a while back.

MazingerDUDE?

 

[AlNom]

Both of them try to remain unbiased to the best of human ability. They are both equally critical of both the PS3 and X360 when it warrants it.

Just a general, friendly reminder that the thread is not about writing style. Let's try to focus here please.

 

[Billy Idol]

Babarian, as the PS3 framerate does not seem this high:

did you ever think about capping it to 30Hz and use the extra cycles to implement a high fidelity motion blur instead?

 

[Statix]

too bad this is not how most people will recognize it instead of pushing one console they will view it as poor porting when its obvious that you guys utilized the spus and even took a look at mlaa.

On the same token, I'm pretty sure the engineers could have prioritized PS3 and SPU development a little further still, and made it more of an emphasis/concern in architecting the development. In that way, certain effects could have been implemented that perform just as well--or even BETTER--on the PS3. Alas, the additional graphic effects that were chosen in the end have resulted in a gulf of performance in the 360's favor this time around, unfortunately. If we're were to see certain effects that were implemented in the PS3's favor performance-wise instead, and leveraged SPU usage a huge amount, then we might see a product much closer to platform parity. Lords of Shadow is an example of this, where many of the effects and engine decisions were architected mostly around the PS3's strengths and hardware, and we can all see the positive results of that. Keeping in mind fully, however, than politics and money might have (direct or indirect) effect on how much developmental attention a particular console receives.

Btw, "considering" MLAA is not a guaranteed indicator that the PS3 devs at Treyarch gave the platform the attention it needs for excellent performance... or even AS MUCH attention as the other version(s).

 

[Statix]

Babarian, as the PS3 framerate does not seem this high:

did you ever think about capping it to 30Hz and use the extra cycles to implement a high fidelity motion blur instead?

I certainly wouldn't mind a good motion blur effect on a Call of Duty title, but in the peformance analysis videos, it's apparent that the PS3 version drops close enough to even 30 fps in certain cases where it would be a negligible act to cap the game to 30 hz anyway. Although, personally, from what I've seen based on PS3 exclusive titles at least, I feel the PS3 is the platform better suited for implementing good-quality per-pixel motion-blur (as we see in numerous PS3 titles such as Motorstorm 1, 2, 3, Uncharted 2, God of War 3, and Killzone 1 and 2); the BIG IF here is that this effect might require a huge amount of devotion or even customization/modification of the engine to optimize the PS3 engine on the part of the developers of Treyarch... and I'm not entirely certain that they would have either the talent nor the resources (or perhaps even care) to priotize the PS3 engine that much.

I personally think the Lords of Shadows developers should be a role model for all multiplatform developers, just for the level of platform parity they were able to achieve, with all the graphical bells and whistles they were able to implement on both platforms (full 720p albeit no AA, per-pixel motion-blur, god ray tech, etc, high framerate, and detailed textures, etc.). They made the PS3 engine a huge priority from the very beginning, and it shows.

 

[Billy Idol]

I certainly wouldn't mind a good motion blur effect on a Call of Duty title, but in the peformance analysis videos, it's apparent that the PS3 version drops close enough to even 30 fps in certain cases where it would be a negligible act to cap the game to 30 hz anyway. Although, personally, from what I've seen based on PS3 exclusive titles at least, I feel the PS3 is the platform better suited for implementing good-quality per-pixel motion-blur (as we see in numerous PS3 titles such as Motorstorm 1, 2, 3, Uncharted 2, God of War 3, and Killzone 1 and 2); the BIG IF here is that this effect might require a huge amount of devotion or even customization/modification of the engine to optimize the PS3 engine on the part of the developers of Treyarch... and I'm not entirely certain that they would have either the talent nor the resources (or perhaps even care) to priotize the PS3 engine that much.

I can understand that you are dissapointed...but I think we should keep the discussion free of attacks, I for myself am happy that Babarian is willing to share some insight , this probably helps us to understand the circumstances and the background of game development a little bit better...which is one of the reasons I visit this forum.

 

[Scott_Arm]

Yeah, backhanded remarks directed to the devs and artists isn't the greatest thing that's happened to this forum. I can understanding wanting answers, but keeping it civil would be nice, so they will want to keep posting here. Rather than suggesting they aren't talented or dedicated enough, or that they have been bribed or coerced in some manner, I'd let them speak their mind with the understanding that they have NDAs and PR people that don't want them talking about certain things.

 

[Barbarian]

Hey did you guys have to go with a lower poly count (generally speaking) to accommodate 3d? If you did, then maybe a lower poly count helped reduce the msaa performance hit?

The PS3 is sensitive to vertex counts, so we did optimize for that reason, but particularly for MSAA I didn't think it mattered? On X360 you could incur a hit due to tiling, but COD doesn't tile anyway.
MSAA is bandwidth sensitive, maybe it matters where your render targets are (main vs vram). Perhaps in GOW's situation it was different than COD's. I don't know.

 

[Trejser]

The SPUs are pretty heavily used. A lot of engine code runs on them, physics, sound, graphics prep, GPU submission, culling, dynamic geo generation etc.
On 360 the situation is similar, every HW thread is heavily used.

Thanks

 

[Silent_Buddha]

MazingerDUDE?

That's him, thanks. I was going nuts trying to remember his handle. It's a shame he doesn't post here anymore, he had some great insights and analysis of games IQ. May not have always agreed with him on everything but he always offered well thought out analysis.

Regards,
SB

 

[Laa-Yosh]

In that way, certain effects could have been implemented that perform just as well--or even BETTER--on the PS3.

And you know that better because of why exactly???

 

[AbbA]

Old tricks that pushes Killzone3 and other Ps3's first party on another league.

 

[corduroygt]

Does Treyarch often exchange ideas with Naughty Dog, like IW did?

 

[bkilian]

Old tricks that pushes Killzone3 and other Ps3's first party on another league.

Lead console is a huge influence on design and performance. I suspect KZ3 uses all new tricks.

 

[(((interference)))]

It's a complex answer, but let's just say, the 360 was pushed hard, to a place where the PS3 couldn't go with the old tricks. Most of the time the battle was fitting the game in memory, and often to get performance you need to trade even more memory. I can go into details but with such a high profile title I'll quickly get in trouble.

So it seems like the old PS3 RAM disadvantage rearing itself again, btw does anyone know if we actually have some sort of number for the current MB difference between the two (with latest firmware)?

I don't have Black Ops yet so can't say definitively but it doesn't look like a downgrade from MW2 (many people are posting like it's a night and day difference), for one the character models are definitely better than MW2s. As for textures, No COD game has ever had good texture work and I can't see Black Ops being any worse than its peers.

It's also interesting to note that in BO the shadow filtering is worse on PS3, when for MW2 it was the other way round. (and indeed for most multiplat titles, like Far Cry 2 due to the free PCF you get on the RSX)
http://images.eurogamer.net/assets/articles//a/8/3/8/5/7/7/Shadow_01_360.jpg.jpg
http://images.eurogamer.net/assets/articles//a/8/3/8/5/7/7/Shadow_01_PS3.jpg.jpg
http://images.eurogamer.net/assets/articles//a/8/3/8/5/7/7/Shadow_02_360.jpg.jpg
http://images.eurogamer.net/assets/articles//a/8/3/8/5/7/7/Shadow_02_PS3.jpg.jpg

Any reason for this?

 

[joker454]

The PS3 is sensitive to vertex counts, so we did optimize for that reason, but particularly for MSAA I didn't think it mattered? On X360 you could incur a hit due to tiling, but COD doesn't tile anyway.
MSAA is bandwidth sensitive, maybe it matters where your render targets are (main vs vram). Perhaps in GOW's situation it was different than COD's. I don't know.

Well my memory is starting to get hazy, been out of the game for a while now But from what I recall msaa on ps3 is affected by both poly count and bandwidth. If I remember right the previous cod game on ps3 hovered between 40 and 60 fps. For you guys, doubling everything up for 3d maybe maybe would have meant 20 to 30fps. 40fps is playable in 2d mode, but 20fps in 3d mode is borderline...so I was thinking maybe to compensate they lowered the poly count of everything and dropped the res to make 3d mode doable. PS3's msaa has a per primitive cost, so every msaa'd poly you draw adds overhead, so less poly's means faster msaa performance. The msaa resolve step is also time consuming on ps3, but with your guys lower res buffer that might have helped it along as well. So it's a guess on my part...but I was thinking that maybe using lower poly assets and a lower res buffer is what made msaa (and 3d) playable for you guys on ps3. For the render targets, they matter if you over saturate one bus. Like if you do everything in vram them the vram bus is getting heavily worked while the dram bus could be snoozing, so you have to split all those work loads across both pools of memory to share the load. Lower res on ps3 will also make it less likely that bus saturation would happen.

But like I said, just a guess...I haven't played the new cod just yet. Although that Pentagon lady does look quite fine I will be getting the game eventually, I love the cod series.

 

[AbbA]

The PS3 is sensitive to vertex counts,

The SPU are the way.

 

[Billy Idol]

Babarian, did you use the SPUs for lighting like for instance the Blur devs explained in the DF interview?

 

[patsu]

They are already heavily used. I suspect it's a long, complex story if they are reusing old engine for 3D (Any project and manpower complications ?) ^_^

joker454 may be right too.