IEEE article about Insomniacs and Resistance.

[chris1515]

http://www.spectrum.ieee.org/dec06/4745

They dedicate two SPE for collisions:

Bringing a game to life on the Cell is a tightly syncopated process. It revolves around queries sent by the PPE to the team of SPEs. The queries request information on real-time events—such as at what point a piece of shrapnel hits an object in the game. By off-loading functions to the eight SPEs, the system has more time to devote to the delectable details: more characters onscreen, more complex artificial intelligence routines, more realistic skeletal structures within the game characters’ bodies, and, overall, an environment that makes you feel like you are inside the game. There is surround sound instead of stereo, with over 100 sounds happening simultaneously versus the 24 possible on the PlayStation 2. In Ratchet & Clank on the PlayStation 2, Insomniac was able to support 10 players competing against each other online; in Resistance: Fall of Man, they set a new record—40. On the PlayStation 2, a character could have only 30 different animated movements in a game; on the PS3, there are over 330. The payoff: the characters won’t resemble awkward manikins anymore—they grimace, scowl, and follow you with their eyes.

So how do programmers decide which tasks the PPE should be doing and which tasks the SPE should tackle? Alex Hastings asks two key questions about each task to make the choice. First, would the task take up a lot of the PPE’s time if it ran there? And second, is it the kind of job that lends itself to what the SPEs do well? “We looked for the easiest wins first,†he says. Animation and calculating collisions between objects are perfect fits, says Hastings. So those are the primary jobs Resistance doles out to the SPEs.

Even such perfect fits require some compromises. Ideally, software could automatically allocate tasks to whichever of the SPEs has the most time on its hands, but in order to simplify the programming, Insomniac was forced to dedicate two SPEs exclusively to collisions. Two processors are needed in the most demanding situation, one with lots of players, monsters, and bullets all moving around at once. “In games you’re more concerned about the worst-case scenario rather than the average,†explains Hastings. If you aim for the average, then there will be many times when the processors can’t finish the job in time and the game stalls. But by the same reasoning, most of the time those two processors aren’t being used to the fullest.

At the third page, they explain a bit how they divide worload between PPE and SPEs.

 

["Nerve-Damage"]

^^ Nice find (+rep)


Edit: The guys & gals at Insomniacs are top-notch all the way.

 

[Crossbar]

Ultimately, in future games, Insomniac will try to get almost all tasks running on the SPEs. “The holy grail that people writing games on the Cell are ultimately trying to reach is to get…the real highest-level decision making [onto the SPEs],” says Hastings. “I think that, based on where we are now, that’s still a few years away.”

The future looks bright. :smile:

Still I would like to read these other articles in the same issue, though they may be a bit old, perhaps someone who gets it could post some comments:


Multimedia monster [supercomputer on a single chip]
Moore, S.K.
Spectrum, IEEE, vol.43, no.1, pp. 20- 23, Jan. 2006

Abstract
This paper presents a microprocessor jointly developed by IBM, Sony, and Toshiba, called Cell Broadband Engine Architecture (Cell). Originally conceived to power Sony's third-generation game console, the Playstation 3, Cell is a combination of general-purpose and multimedia processors. It defies an exact comparison with upcoming chips, but it's thought to be more powerful than the chips driving competing game systems. Cell can calculate at a blazing speed, in part, because it's made up of nine processors on a single chip of silicon, optimized for the kind of real-time calculations needed in today's broadband, media-rich environment. A specially designed 300-gigabit-per-second bus knits the processors into a single machine, and interface technology gives it fast access to memory and other off-chip systems.


Synergistic Processing in Cell's Multicore Architecture
Gschwind, M.; Hofstee, H.P.; Flachs, B.; Hopkins, M.; Watanabe, Y.; Yamazaki, T.
Micro, IEEE, vol.26, no.2, pp. 10- 24, March-April 2006

Abstract
Eight synergistic processor units enable the Cell Broadband Engine's breakthrough performance. The SPU architecture implements a novel, pervasively data-parallel architecture combining scalar and SIMD processing on a wide data path. A large number of SPUs per chip provide high thread-level parallelism.


Xbox 360 System Architecture
Andrews, J.; Baker, N.
Micro, IEEE, vol.26, no.2, pp. 25- 37, March-April 2006

Abstract
The authors talk about the Xbox 360's high-level technical requirements, a short system overview, and details of the CPU and the GPU. They describe their architectural trade-offs and summarize the system's software programming support.

 

[Carl B]

Well, I can definitely say that Resistance has great collision detection. Playing some of the later vehicle levels today I couldn't even manuever, the debris scattered around the field was having such a deliterious effect! Frustrating while playing, but impressive from a technical standpoint.

 

[LunchBox]

eight SPE's?

Bringing a game to life on the Cell is a tightly syncopated process. It revolves around queries sent by the PPE to the team of SPEs. The queries request information on real-time events—such as at what point a piece of shrapnel hits an object in the game. By off-loading functions to the eight SPEs, the system has more time to devote to the delectable details: more characters onscreen, more complex artificial intelligence routines, more realistic skeletal structures within the game characters’ bodies, and, overall, an environment that makes you feel like you are inside the game. There is surround sound instead of stereo, with over 100 sounds happening simultaneously versus the 24 possible on the PlayStation 2. In Ratchet & Clank on the PlayStation 2, Insomniac was able to support 10 players competing against each other online; in Resistance: Fall of Man, they set a new record—40. On the PlayStation 2, a character could have only 30 different animated movements in a game; on the PS3, there are over 330. The payoff: the characters won’t resemble awkward manikins anymore—they grimace, scowl, and follow you with their eyes.

Very nice article though plus rep!

 

[Shifty Geezer]

Nice article find? Old news!

dcforest posted this about 18 hours earlier!
http://www.beyond3d.com/forum/showpost.php?p=884924&postcount=495

 

[chris1515]

Nice article find? Old news!

dcforest posted this about 18 hours earlier!
http://www.beyond3d.com/forum/showpost.php?p=884924&postcount=495

I'm sorry, I have not seen the dcforest post. A mod can lock the thread.

 

[Farid]

The thing is, all the PS3 launch games, and should I say all the games currently in development, are litteraly wasting SPE cycles... Because they can and because their code is not perfectly, or even remotely close, suited to Cell SPEs.

DeanoC's prophetic prevision about future PS3 games' code being more and more SPE centric, leaving the PPE core to lesser tasks, is spot on.

I'm sorry, I have not seen the dcforest post. A mod can lock the thread.

It was a post in the game forum.
The topic is obviously technological, so there's no reason to lock that thread.

 

[Shifty Geezer]

I'm sorry, I have not seen the dcforest post. A mod can lock the thread.

This is the better place to discuss it and I say you're right to post it here. But those who think it's new need to get out more!

 

[NavNucST3]

The future looks bright. :smile:

Still I would like to read these other articles in the same issue, though they may be a bit old, perhaps someone who gets it could post some comments:


Multimedia monster [supercomputer on a single chip]
Moore, S.K.
Spectrum, IEEE, vol.43, no.1, pp. 20- 23, Jan. 2006

Abstract
This paper presents a microprocessor jointly developed by IBM, Sony, and Toshiba, called Cell Broadband Engine Architecture (Cell). Originally conceived to power Sony's third-generation game console, the Playstation 3, Cell is a combination of general-purpose and multimedia processors. It defies an exact comparison with upcoming chips, but it's thought to be more powerful than the chips driving competing game systems. Cell can calculate at a blazing speed, in part, because it's made up of nine processors on a single chip of silicon, optimized for the kind of real-time calculations needed in today's broadband, media-rich environment. A specially designed 300-gigabit-per-second bus knits the processors into a single machine, and interface technology gives it fast access to memory and other off-chip systems.


Synergistic Processing in Cell's Multicore Architecture
Gschwind, M.; Hofstee, H.P.; Flachs, B.; Hopkins, M.; Watanabe, Y.; Yamazaki, T.
Micro, IEEE, vol.26, no.2, pp. 10- 24, March-April 2006

Abstract
Eight synergistic processor units enable the Cell Broadband Engine's breakthrough performance. The SPU architecture implements a novel, pervasively data-parallel architecture combining scalar and SIMD processing on a wide data path. A large number of SPUs per chip provide high thread-level parallelism.


Xbox 360 System Architecture
Andrews, J.; Baker, N.
Micro, IEEE, vol.26, no.2, pp. 25- 37, March-April 2006

Abstract
The authors talk about the Xbox 360's high-level technical requirements, a short system overview, and details of the CPU and the GPU. They describe their architectural trade-offs and summarize the system's software programming support.

I'll see if I can find them, I have the magazines around here somewhere, worst case I should be able to logon to the site I believe for the archived articles. I will PM you if I find them.

 

[rounin]

I was able to get them through my university library website. Perhaps those who go to college/university can try it that way.

 

[StefanS]

I was able to get them through my university library website. Perhaps those who go to college/university can try it that way.

same here. Check the electronic magazines of your university.