The Game Technology discussion thread *Read first post before posting*

[assurdum]

So, there's really no reason not being able to use triple buffer on the 360 eh? I do get your point, however it's not like the 360's got infinite amount of power. What puzzles me is that there are those games that would clearly benefit from the triple buffer that they don't do so in the 360, for example, Fallout 3. Sure, it runs smoother than the PS3 version, but it still tears considerably especially on the close up slow-mo scenes which in turn, affects significantly to the overall IQ. It's not that the game use better quality textures or anything (in fact it's got worse textures) There's really no logical reason not to use the triple buffer here.

As for the input lag, I'm not sure in practice (since I'm no dev ), but in theory, dynamic triple buffer would reduce input lag (it would lag just as much as the double buffer with v-sync) if you make use of the third buffer when the frame rate dips below 30. (in this case it will lag only when there're frame dips) I participated Uncharted 2 beta, and didn't really feel any more input lag over

I wonder any other dev here can provide a clear answer, I don' think it's purely a coincident that you don't see the triple buffer on neither multi-platform, nor exclusive on the 360 .

BTW, CryEngine 3 should be near complete as they'd be shipping out SDKs on coming month.

I think we could speak for hours but the 'facts' what shows?: triple buffering very rare on the 360 and although the multi benefits are more on the 360, it's more easy to see triple buffering on the ps3 than the reverse, even some titles with ue3 on the ps3 use triple buffering (50 cents, wolfenstein etc). I never seen triple buffering in the ue3 titles on 360. And capcom, probably one of the best developers on the 360 to achieve concrete results, why prefers sacrifice IQ whether triple buffering not require too much? A coincidence? I doubt it.

 

[joker454]

Qick answers because I'm heading out:

That's in turn what may hold the 360 down a little in some multi-platform titles that actually use this aspect of the PS3, you may need the extra RAM for caching.

You can do the same on the 360 version, the only difference is that the dvd is faster than the blu-ray in fetching stuff, and the hdd mechanism is optional for non hdd models, so those machines will have more pop. Many games have done disc+hdd caching already.

Sure, it runs smoother than the PS3 version, but it still tears considerably especially on the close up slow-mo scenes which in turn, affects significantly to the overall IQ.

'Considerable tear' is all relative, and usually blown out of proportion on forums. People typically notice tearing less than vsync frame drops, and even less so if the tearing usually happens way up top on the screen. 'Unplayable' on forums is frequently totally fine in the field.

I'm not sure in practice (since I'm no dev ), but in theory, dynamic triple buffer would reduce input lag (it would lag just as much as the double buffer with v-sync)

To guarantee no tears or vsync drops, you triple buffer and use the third buffer as the display source, which is where the lag comes from. If you can do double buffer vsync 99% of the time with no frame drops then you don't need triple buffer anyways.

A coincidence? I doubt it.

You are right it's not a coincidence. It's because you just don't need triple buffer on 360, but it's definitely possible Do you also find it a coincidence that most PS3 games don't have MSAA? Does that mean that PS3 is not capabable of msaa? Likewise, is it coincidence that most PS3 games used reduced buffers for transparencies? Does that mean that the PS3 hardware is incapable of rendering transparencies at full res? No coincidences here, there's logical reasons for everything.

 

[assurdum]

You are right it's not a coincidence. It's because you just don't need triple buffer on 360 , but it's definitely possible Do you also find it a coincidence that most PS3 games don't have MSAA? Does that mean that PS3 is not capabable of msaa? Likewise, is it coincidence that most PS3 games used reduced buffers for transparencies? Does that mean that the PS3 hardware is incapable of rendering transparencies at full res? No coincidences here, there's logical reasons for everything.

I continue to miss your point. The 360 need triple buffering how ps3 or pc. But it's evident on 360 there are more disadvantages than on the ps3. However if for you is better to say don't need of triple buffer, not problem. The next time when someone claims lacks of MSAA or hd transparancies on the ps3 I could to use the same 'sweet' quote

 

[MazingerDUDE]

'Considerable tear' is all relative, and usually blown out of proportion on forums. People typically notice tearing less than vsync frame drops, and even less so if the tearing usually happens way up top on the screen. 'Unplayable' on forums is frequently totally fine in the field.

You are right it's not a coincidence. It's because you just don't need triple buffer on 360, but it's definitely possible Do you also find it a coincidence that most PS3 games don't have MSAA? Does that mean that PS3 is not capabable of msaa? Likewise, is it coincidence that most PS3 games used reduced buffers for transparencies? Does that mean that the PS3 hardware is incapable of rendering transparencies at full res? No coincidences here, there's logical reasons for everything.

Well, you could say the same thing for slightly blurrier textures, slightly lower running res, and MSAA vs QAA etc. People don't usually notice such thing as console parity, and it is blown out of portion on internet forums. That doesn't mean that these features are not important. Devs are competing to push the consoles to boundaries in order to achieve maximum visuals, and v-sync is just as important as any other features that you have mentioned. It's apparent that the 360 is more capable than PS3 to your average devs, but its power is still finitie, and there're number of games that would benefit from triple buffer. Yes there're far fewer games that have MSAA on PS3, and we know why. 360 is just more capable with MSAA and alpha thanks to the edram. Now, there're even fewer games, (in fact close to none) on 360 that have triple buffer, and the only logical reason I can think of is because 360 is less capable of utilizing it. It'd be nice if you could tell us why

 

[JPT]

360 is just more capable with MSAA and alpha thanks to the edram. Now, there're even fewer games, (in fact close to none) on 360 that have triple buffer, and the only logical reason I can think of is because 360 is less capable of utilizing it. It'd be nice if you could tell us why

Haven't he already said, that it is no need to do triple buffering to achieve parity with PS3? And because it causes input lag, its not desirable to use it.

 

[MazingerDUDE]

Haven't he already said, that it is no need to do triple buffering to achieve parity with PS3? And because it causes input lag, its not desirable to use it.

And I said there're games that would clearly benefit from triple buffer, for example Mass Effect. The game's got some serious frame rate issues which accompany with severe screen tearing. It is a RPG game, so extra 16.67ms latency isn't much of a deal breaker.

Also you'd already get 33~50ms latency in a 30 fps game with double buffer v-sync, extra 16.67ms won't break a game as seen in practice.

 

[brain_stew]

And I said there're games that would clearly benefit from triple buffer, for example Mass Effect. The game's got some serious frame rate issues which accompany with severe screen tearing. It is a RPG game, so extra 16.67ms latency isn't much of a deal breaker.

Also you'd already get 33~50ms latency in a 30 fps game with double buffer v-sync, extra 16.67ms won't break a game as seen in practice.

You should be getting less input lag with triple buffer v-sync compared to standard double buffer v-sync, not more. At least that's how it should work in theory and has always been my observation when experimenting with it on the PC side.

 

[joker454]

And I said there're games that would clearly benefit from triple buffer, for example Mass Effect. The game's got some serious frame rate issues which accompany with severe screen tearing. It is a RPG game, so extra 16.67ms latency isn't much of a deal breaker.

Triple buffering isn't a magic cure all for frame rate. If you have bad frame rate before, you will still have bad frame rate with triple buffering. In Mass Effects case they probably figured why bother since frame rate would be bad before and after anyways, so may as well just reclaim and use the extra memory. It's more useful for borderline cases where you're frame rate is good, but the tearing is just a bit too much. For most 360 games tearing isn't that bad, so they don't bother with triple, there is just no need.

The unified video card helps somewhat because the entire video card is always at work regardless of the scene, whereas on PS3 the gpu will stall significantly more for a variety of reasons, and the amount of stalling will vary based on the scene, meaning it's more likely that even if you have the game working 30fps most of the time, you can still end up with situations where suddenly the video hardware falls too far behind and you get a tear right in the middle of the screen. Triple buffering helps in those cases on PS3. There are many cases that can cause performance spikes on the PS3's gpu, none of which apply to the 360, which is one reason you will see triple much more on PS3.

Some simple cases. All of a sudden there are many transparencies on screen. PS3 did ok last frame but chokes now, maybe triple would help there. 360 doesn't care either way, more transparencies will not cause a performance spike. Or, you are suddenly put in a scene that requires more texture sampling than normal, which eats up shader alu time on PS3, might lead to a performance spike. It might be a small spike, but enough to move that tear down to the middle of the screen. 360 won't be affected. Or, you end up in a situation which is more pixel heavy than normal and of course the vertex units on rsx can't help, so you get hit with a performance spike, again small but maybe enough to make a not noticeable tear much more noticeable. 360 again is not affected. And so on...

Performance in general is much smoother on 360, it is much more capable of handling spikes in rendering demands. So if you can get your game in general to run smooth then you are ok on the 360, the gpu will handle spikes for you. PS3 is not in the same boat so triple buffering is a decent solution to absorb some of that.

 

[MazingerDUDE]

Triple buffering isn't a magic cure all for frame rate. If you have bad frame rate before, you will still have bad frame rate with triple buffering. In Mass Effects case they probably figured why bother since frame rate would be bad before and after anyways, so may as well just reclaim and use the extra memory. It's more useful for borderline cases where you're frame rate is good, but the tearing is just a bit too much. For most 360 games tearing isn't that bad, so they don't bother with triple, there is just no need.

The unified video card helps somewhat because the entire video card is always at work regardless of the scene, whereas on PS3 the gpu will stall significantly more for a variety of reasons, and the amount of stalling will vary based on the scene, meaning it's more likely that even if you have the game working 30fps most of the time, you can still end up with situations where suddenly the video hardware falls too far behind and you get a tear right in the middle of the screen. Triple buffering helps in those cases on PS3. There are many cases that can cause performance spikes on the PS3's gpu, none of which apply to the 360, which is one reason you will see triple much more on PS3.

Some simple cases. All of a sudden there are many transparencies on screen. PS3 did ok last frame but chokes now, maybe triple would help there. 360 doesn't care either way, more transparencies will not cause a performance spike. Or, you are suddenly put in a scene that requires more texture sampling than normal, which eats up shader alu time on PS3, might lead to a performance spike. It might be a small spike, but enough to move that tear down to the middle of the screen. 360 won't be affected. Or, you end up in a situation which is more pixel heavy than normal and of course the vertex units on rsx can't help, so you get hit with a performance spike, again small but maybe enough to make a not noticeable tear much more noticeable. 360 again is not affected. And so on...

Performance in general is much smoother on 360, it is much more capable of handling spikes in rendering demands. So if you can get your game in general to run smooth then you are ok on the 360, the gpu will handle spikes for you. PS3 is not in the same boat so triple buffering is a decent solution to absorb some of that.

You're a bit off topic here, this is not about PS3 vs 360. Sure the 360 is more capable in general, but it's all in relative terms and that doesn't mean that there's absolutely no need for it because in practice, there're those games that exhibit some serious screen tearing such as Mass Effect. Of course triple buffer doesn't magically increase your frame rate, but it is the magic cure for screen tearing, and there're close to none to make use of it in the 360, even in the games that would clearly benefit from it.

The question is whether a use of triple buffering is more limited on 360 over PS3 or not.

 

[joker454]

You're a bit off topic here, this is not about PS3 vs 360.

It's exactly on topic actually. You asked why it appears on PS3 and not on 360, so I gave you examples why it's seen on one and not the other.

The question is whether a use of triple buffering is more limited on 360 over PS3 or not.

It's not.

 

[MazingerDUDE]

It's exactly on topic actually. You asked why it appears on PS3 and not on 360, so I gave you examples why it's seen on one and not the other.

It's not.

That's fair enough. So, the lack of triple buffer on 360 even for the games that would benefit from it, is just purely coincidental right?

 

[JPT]

That's fair enough. So, the lack of triple buffer on 360 even for the games that would benefit from it, is just purely coincidental right?

Because puttting extra resources into a version to make it better than the other version when its not needed, means more expensive product to make.
When it comes down to it, its about making money, so why polish when you do not need it, by needing we are talking about market acceptance by the fanboys.

 

[assurdum]

Just watch the results: the triple buffer if you want, on the ps3 works without great lag (RE 5 a part). The only plausible reason is the ps3 hardware is more suitable for the developer (probably thanks to cell spe and lack of edram) . I don't understand why on the ps3 must be only for tecnical limitations and in the 360 only for the great hardware benefits of double buffer who becomes suddenly the high better standard on the console IQ. The joker post about wonderful gpu of 360 ( yeah great gpu, never doubt of that, compared rsx, but is ot) again sound like too in favour of 360 hardware. The double buffer tendency to be better on 360 (not ever however) can't be the only reason of the triple buffer lack. Not have sense. Because there are more games who suffer visible screen tearing on the 360 & not on ps3. So why? I'm reading cost. And cost not mean more difficult to have triple buffer implementation on the 360 too? But again is an another supposition; the only explanation it wasn't a mix of low cost & best performance in a game? Why every choice made on the ps3 is cause only to hardware limitations and on 360 to hardware advantages? Why screen tearing becomes so terrible on the ps3 to justify triple buffer while on 360 are only subjective and the lag is a worsen perspective? Sound like a bit ... well...ok nevermind .

 

[liolio]

Just watch the results: the triple buffer if you want, on the ps3 works without great lag (RE 5 a part).
The only plausible reason is the ps3 hardware is more suitable for the developer (probably thanks to cell spe and lack of edram) . I don't understand why on the ps3 must be only for tecnical limitations and in the 360 only for the great hardware benefits of double buffer who becomes suddenly the high better standard on the console IQ. The joker post about wonderful gpu of 360 ( yeah great gpu, never doubt of that, compared rsx, but is ot) again sound like too in favour of 360 hardware. The double buffer tendency to be better on 360 (not ever however) can't be the only reason of the triple buffer lack. Not have sense. Because there are more games who suffer visible screen tearing on the 360 & not on ps3. So why? I'm reading cost. And cost not mean more difficult to have triple buffer implementation on the 360 too? But again is an another supposition; the only explanation it wasn't a mix of low cost & best performance in a game? Why every choice made on the ps3 is cause only to hardware limitations and on 360 to hardware advantages? Why screen tearing becomes so terrible on the ps3 to justify triple buffer while on 360 are only subjective and the lag is a worsen perspective? Sound like a bit ... well...ok nevermind .

That's indeed a lot of suppositions.
We know for sure that few devs use triple buffering on ps3 (they make presentation about their tech). It's not obvious that they had to use triple buffering Joker gave some explanations about how it can help leveraging variations in workload, it can also be that they decide that the memory hit is worse it in term of IQ and overall experience.
You're trying too hard to make a point about triple buffering point is that on the ps360 you can live without it and have minimal torn frames. And actually there are game that tears on the ps3 and not on the 360... (more actually).

I've something to ask you why nobody (of we heard about) use log luv 16 on the 360? Basically it's because in most case they think fp10 is good enough (+ support for alpha blending) thus devs don't dare to use extra gpu cycles for a better effect.
Why nobody try to do some culling via the vmx units? Basically it would not be as fast as SPU but it could be achieve at acceptable performances (data are in likely to be in cache, code could reach pretty high efficiency), it would free some resources on the gpu. Basically as Joker once hinted most devs doesn't think its worst the effort.
Overall I guess all this tearing/triple buffering is a non issue on both systems. More problems are due to lack of time/optimization or late realization that perfs goals was too high, huge CPU problems (see Sacred2 and TB first hand insight), etc.
What Insomniac, ND does is almost the best of the business, they may have to use it and by the way it offers some nice IQ enhancement or more simply they could afford both in memory hit and little extra latencies induced.

 

[assurdum]

That's indeed a lot of suppositions.
We know for sure that few devs use triple buffering on ps3 (they make presentation about their tech). It's not obvious that they had to use triple buffering Joker gave some explanations about how it can help leveraging variations in workload, it can also be that they decide that the memory hit is worse it in term of IQ and overall experience.
You're trying too hard to make a point about triple buffering point is that on the ps360 you can live without it and have minimal torn frames. And actually there are game that tears on the ps3 and not on the 360... (more actually).

I've something to ask you why nobody (of we heard about) use log luv 16 on the 360? Basically it's because in most case they think fp10 is good enough (+ support for alpha blending) thus devs don't dare to use extra gpu cycles for a better effect.
Why nobody try to do some culling via the vmx units? Basically it would not be as fast as SPU but it could be achieve at acceptable performances (data are in likely to be in cache, code could reach pretty high efficiency), it would free some resources on the gpu. Basically as Joker once hinted most devs doesn't think its worst the effort.
Overall I guess all this tearing/triple buffering is a non issue on both systems. More problems are due to lack of time/optimization or late realization that perfs goals was too high, huge CPU problems (see Sacred2 and TB first hand insight), etc.
What Insomniac, ND does is almost the best of the business, they may have to use it and by the way it offers some nice IQ enhancement or more simply they could afford both in memory hit and little extra latencies induced.

And there are games totally vsync on ps3 and full of tearing on 360, never the reverse. So where is the point? when a developer use the triple buffer on the ps3 or is the only solution or is the best developer in the universe. But when lack something on 360 is only thanks of its hardware better performance in the rest...wtf? how is possible to think this point of view is more creditable?

 

[AlNom]

And there are games totally vsync on ps3 and full of tearing on 360, never the reverse.

There are games where both versions are v-locked...


Anyways, ran across this somewhat intriguing comment by Shawn Hargreaves:

http://forums.xna.com/forums/p/31951/182981.aspx#182981

Native 360 games have access to a kind of weird not-really-triple-buffering mode that some games use, but which is not available through the XNA Framework.

Any idea what this is, joker

Another interesting blog post on vsync related to threading: http://www.luminance.org/gruedorf/2009/07/01/threaded-enddraw-in-xna

 

[assurdum]

There are games where both versions are v-locked...


Anyways, ran across this somewhat intriguing comment by Shawn Hargreaves:

http://forums.xna.com/forums/p/31951/182981.aspx#182981

Any idea what this is, joker


Another interesting blog post on the matter: http://www.luminance.org/gruedorf/2009/07/01/threaded-enddraw-in-xna

True and I never said triple buffer is impossible on 360.

 

[liolio]

And there are games totally vsync on ps3 and full of tearing on 360, never the reverse. So where is the point? when a developer use the triple buffer on the ps3 or is the only solution or is the best developer in the universe. But when lack something on 360 is only thanks of its hardware better performance in the rest...wtf? how is possible to think this point of view is more creditable?

No I don't think that what Joker implied with his post. Triple buffering is nothing special, it's mostly only have a memory impact. It's activable on hardware on PC realm through drivers since a lot of time. I can't think of any technical limitation that would prevent its use on the 360.
Between there quiet some games where tearing is more present on the ps3 renditions.
We never know why a given version of a tear or not. Look at sacred2 TB explained that tearing and frame drop are mostly due to quiet significant CPU problem, I'm not sure about that triple buffering would have helped much, it can only hide so much variations.
Some Capcom games have a tearing problem when upscaled to 1080p, basically we have no clue about what capcom does that have this consequence. At 720p the problem is not here.

 

[assurdum]

No I don't think that what Joker implied with his post. Triple buffering is nothing special, it's mostly only have a memory impact. It's activable on hardware on PC realm through drivers since a lot of time. I can't think of any technical limitation that would prevent its use on the 360.
Between there quiet some games where tearing is more present on the ps3 renditions.
We never know why a given version of a tear or not. Look at sacred2 TB explained that tearing and frame drop are mostly due to quiet significant CPU problem, I'm not sure about that triple buffering would have helped much, it can only hide so much variations.
Some Capcom games have a tearing problem when upscaled to 1080p, basically we have no clue about what capcom does that have this consequence. At 720p the problem is not here.

Vsync nothing of special What do you talking about? It's the best tearing cure. So why don't use it if not cause any great problems on the 360? And re5 yes have a large amount of tearing too at 720p in some moments. So because in some games are more tearing on the ps3, it's more relevant than the game who have triple buffer without problems vs 360 with visible tearing? Why to persist of this argument? Could be depending of more 'flexibility' of the memories unit on the ps3 share in two parts & total absence of tiling problems?

 

[brain_stew]

From what I picked up in Derek Wilson's recent article (+comments) on triple buffering is that DX9 support for triple buffering is iffy at best and that it requires more work than it should. The fact that they confusingly call the standard 3 frame render ahead "triple buffering" certainly doesn't help support on the PC side either.

Perhaps its simply a case that implementing triple buffering on the (DirectX based) 360 isn't the simple check box process that it should be and that weird naming conventions are confusing developers as well?