SPU-Based Deferred Shading in BATTLEFIELD 3 for Playstation 3

[Malacite]

Re: SPU-Based Deferred Shading in BATTLEFIELD 3 for Playstation 3

I would love to get BF3 for PC, but I feel like I'll be more comfortable on my PS3. I figure by the time I get my next PC it should be able to run BF3 on max np with the current tech trends & price drops (also hoping to do the same with XIV)

Also, again it's important to point out that Blu-Ray allows for much high quality, uncompressed data which lightens the burden on the RSX where as the Xenon has a larger workload (which it takes in strides). My personal opinion though is that the GPU comparisons are meritless anyway as they are made by 3rd parties (ATI and nVidia) where as SONY helped create & owns Blu Ray & Cell (well, they DID own Cell - IIRC they sold it off to Toshiba for God only knows why.)


Gotta say, I wish they'd come through with their original promises but yikes... $840 manufacturing cost? They would have had to have had GTA4 as PS3 only and then some to sell that monster.

[DakAttack]

Re: SPU-Based Deferred Shading in BATTLEFIELD 3 for Playstation 3

Eh? Most texture and 3D model data is held in video ram, so I'm not really sure where you're going with this argument. Fewer, smaller textures and models? Not really. Lower resolution? Also not really. Less detailed game world? Definitely not really.

Find me an Xbox 360 game that renders as much environment as Uncharted 2: Among Thieves on PS3, or renders as many real-time objects as Super Stardust HD, and I might concede your point. As for resolution, there are noticeably more games that render in true 1080p on the PS3 than on the Xbox 360, so again, I have no idea where you're getting that idea from either.

You only get out-of-memory crashes when you aren't managing your memory assets properly, and that can happen just as easily on the Xbox 360 as it can on the PS3 because of the (overall) relatively small amounts of memory resources available overall compared to the expected complexity of graphic output.

Ok, so I don't make this mistake in the future, can you explain to me what use non-GPU RAM is to gaming? I've been under a lot of assumptions that I need to clear up.


On the topic of PC gaming, you can produce a pretty cheap, high-end PC if you start now and have a lot of patience. Outline your rig and watch websites like LogicBuy for deals on the parts you're interested in, and you should save a lot of money. Plus, proper use of overclocking can really stretch your [Canadian] dollar.

[Icemage]

Re: SPU-Based Deferred Shading in BATTLEFIELD 3 for Playstation 3

Ok, so I don't make this mistake in the future, can you explain to me what use non-GPU RAM is to gaming? I've been under a lot of assumptions that I need to clear up.

Ok, quick lesson in console memory configuration commences.

The Xbox 360 has two significant memory resources. 512MB of unified general purpose RAM, plus a 10MB cache of high speed eDRAM which is typically used as a framebuffer for video processing, for a net total of (as you said) 522MB of RAM, though there's not much point in lumping the eDRAM cache with the rest of the unified memory because of how it's used.

The PS3 has 256MB of general purpose RAM, 256MB of high speed GDDR3 video RAM, and a 512KB cache on each of its 7 SPUs for a total of 515.5MB. Like the eDRAM cache on the 360, you really can't include the SPU memory caches as part of general storage capacity, since that's not how they're used in practice.

So what you end up with is the 360 with 512MB of flexible but not-super-fast RAM that can be used in any proportion for video processing or graphics processing, while the PS3 also has 512MB, half dedicated to general purpose processing, and half dedicated to video processing.

On paper, you might think that the Xbox 360 could produce much more impressive graphics than the PS3 because if your game code has a smaller memory footprint, you could dedicate more of its general RAM to graphics and therefore produce a more visually impressive game, right? Except you'd be wrong, because while you "could" use the general memory store on the 360 that way, it's much slower than the eDRAM cache or the PS3's dedicated video RAM, and that would negate most any advantage you'd get from the larger memory allocation.

That's why Microsoft put in the 10MB eDRAM cache on the Xbox 360. It's very fast, and has a huge data pipeline to main memory. So what games on the Xbox 360 do is store the video frames in general memory and send it over into the eDRAM cache for processing. This works really well, but you're limited to whatever you can process inside 10MB, which just so happens to comfortably fit a 1280x720 signal. This is the reason why almost all Xbox 360 games run at 720p or lower, because you really have to make sacrifices to increase the resolution any higher and still fit it inside the eDRAM cache. Ever wonder why Halo 3 runs at 540p? It's because they're actually processing every frame twice for HDR inside the eDRAM.

On the PS3 side, it has more than enough video RAM to handle 1080p output, but its slightly hampered by the fact that its RSX graphics chip isn't as advanced as the one on the Xbox 360. What PS3 developers do is push a lot of the processing for shaders, collisions, etc. onto the SPUs to cover for the fact that the RSX doesn't have some functions built-in.

The rest of the memory is where the game code and logic resides; space to handle AI, inventory, music, etc.

tl;dr The 360 and PS3 produce mostly comparable results in terms of graphics. When developers really drill down and code to the metal, they can get more spectacular results (see: Gears of War 2, Uncharted 2, etc.).


Icemage

[DakAttack]

Re: SPU-Based Deferred Shading in BATTLEFIELD 3 for Playstation 3

What does the PS3 typically use its general purpose RAM for?

[Icemage]

Re: SPU-Based Deferred Shading in BATTLEFIELD 3 for Playstation 3

What does the PS3 typically use its general purpose RAM for?

I'm not quite sure how to take that question.

You need a lot more to run a video game than just the graphics rendering. The code that actually runs the game needs to be stored and executed somewhere; processes the input from your controllers. Playing the music and mixing sound effects that you hear from the speakers. Running the code that keeps you connected to the Internet for online games and leaderboards.

There's also a moderate amount of general RAM on all consoles that is used for the operating system (this is what takes control when you hit the Guide / PS buttons on the controller).

It's basically the same RAM that you use in a PC, and can be used for anything you like.

In the case of the PS3, developers have been slicing away small chunks of the general RAM to use for extra video processing. That's sort of what DICE is doing with the SPUs for deferred shading, and it's why some games like LA Noire look so much better on PS3, because those SPUs are REALLY good at graphics-related processing like advanced shaders.



---------- Post added at 06:53 PM ---------- Previous post was at 06:36 PM ----------

Also, again it's important to point out that Blu-Ray allows for much high quality, uncompressed data which lightens the burden on the RSX where as the Xenon has a larger workload (which it takes in strides).

This isn't correct either.

Blu-ray discs have two primary differences in performance from DVDs.

One, they store more data. This is (generally) not a big deal for anything but the small number of games that use a LOT of art assets; MMOs like DC Universe, large RPGs like Mass Effect 2 and Final Fantasy XIII, and of course Metal Gear Solid 4.

For any game that will fit on the standard Xbox 360 DVD (about 7GB or so), there's not much tangible advantage to Blu-ray; and the vast majority of current games fall under this umbrella.

Two, Blu-ray drives have a fixed data transfer speed no matter where on the disc you're looking. A 12x DVD drive like that in the Xbox 360 reads data much faster from the outside edge of the disc than the inside part of the disc. A good developer will put the most frequently used data on the outside ring of the disc, and rarely used data on the inside of the DVD for this reason. Overall, the DVD will read data faster from that outside ring of the DVD faster than the 2x Blu-ray drive on the PS3, but much slower than the PS3 for data on the inside of the disc. The closer you get to the center of a DVD, the slower the rate that it can be read at.

Also note that the PS3 has the option of installing to the hard drive, since all PS3s have one, and Xbox 360 users can install their games directly to their hard drive, if they have one. This can greatly improve performance since the hard drive is many times faster than either the 12x DVD or 2x Blu-ray drives.

With that said, neither of these should significantly impact Battlefield 3.

My personal opinion though is that the GPU comparisons are meritless anyway as they are made by 3rd parties (ATI and nVidia) where as SONY helped create & owns Blu Ray & Cell (well, they DID own Cell - IIRC they sold it off to Toshiba for God only knows why.)

Oh boy, where to begin?

It's no secret that the PS3 graphics processer is more primitive than the Xbox 360 one. Not by "a lot", but a little. The 360's chip has several notable features which it handles that the PS3's does not. Relatively cost-free 2x anti-aliasing and automatic upscaling are the most significant of those. The first is why a lot of games looked better on the 360 for the first year or so of the PS3's existence, because developers could just sort of slap on 2x MSAA without a lot of effort and make their games look a little cleaner on the 360, but they had to actually work to get AA working on PS3 games, and often with an added computational cost because they didn't know how to properly harness the SPUs that early in the life cycle.

Sony did help develop Blu-ray, but they never sold off the design of Cell to Toshiba. What they did was sell a Cell manufacturing plant to Toshiba a few years ago.. and they actually bought that plant back from Toshiba late last year for about 2/3 of what Toshiba paid for it in the first place.


Icemage

[Mhurron]

Re: SPU-Based Deferred Shading in BATTLEFIELD 3 for Playstation 3

What does the PS3 typically use its general purpose RAM for?

For general purpose uses, I thought that was obvious. It has half dedicated to graphics, and half for everything else.

---------- Post added at 03:17 PM ---------- Previous post was at 03:10 PM ----------

SONY helped create & owns Blu Ray & Cell (well, they DID own Cell - IIRC they sold it off to Toshiba for God only knows why.)

Sony was a partner with Toshiba and IBM in the design and manufacture of the Cell architecture. IBM doing the majority of the design (and holding many of the related patents) as Cell is an outgrowth of their POWER processors, and IBM maintains the reference compiler. Sony and Toshiba were used primarily for fabrication.

[Feba]

Re: SPU-Based Deferred Shading in BATTLEFIELD 3 for Playstation 3

Ok, so I don't make this mistake in the future, can you explain to me what use non-GPU RAM is to gaming?

Come on Dak, you've played XI. I shouldn't need to say "PS2 Limitations", should I?

[Raydeus]

Re: SPU-Based Deferred Shading in BATTLEFIELD 3 for Playstation 3

Don't worry guys, I got it covered.

My next letter to Santa will include a request for 1GB+ RAM for the PS3.

[Malacite]

Re: SPU-Based Deferred Shading in BATTLEFIELD 3 for Playstation 3

This isn't correct either.

Blu-ray discs have two primary differences in performance from DVDs.

One, they store more data. This is (generally) not a big deal for anything but the small number of games that use a LOT of art assets; MMOs like DC Universe, large RPGs like Mass Effect 2 and Final Fantasy XIII, and of course Metal Gear Solid 4.

For any game that will fit on the standard Xbox 360 DVD (about 7GB or so), there's not much tangible advantage to Blu-ray; and the vast majority of current games fall under this umbrella.

Two, Blu-ray drives have a fixed data transfer speed no matter where on the disc you're looking. A 12x DVD drive like that in the Xbox 360 reads data much faster from the outside edge of the disc than the inside part of the disc. A good developer will put the most frequently used data on the outside ring of the disc, and rarely used data on the inside of the DVD for this reason. Overall, the DVD will read data faster from that outside ring of the DVD faster than the 2x Blu-ray drive on the PS3, but much slower than the PS3 for data on the inside of the disc. The closer you get to the center of a DVD, the slower the rate that it can be read at.

Eh?

Relevant segment @ 7:42

[Icemage]

Re: SPU-Based Deferred Shading in BATTLEFIELD 3 for Playstation 3

Eh?

‪Xbox 360 vs. PS3: Round 5 (GPU)‬‏ - YouTube

Relevant segment @ 7:42

That video is somewhat misleading. Texture streaming is a neat trick, but it's not exclusive to the PS3 or Blu-ray. The 360 can do it as well with any game that isn't bumping up against the DVD limit on disc size. It's a bit "easier" to do it with a Blu-ray disc because it's easier to make a game with uncompressed textures that fits onto a 25GB or 50GB disc as opposed to a single 9GB disc, but as I said above, most games aren't (quite) at that 7-8GB limit (some disc space is lost due to DRM).

360 games like Halo Reach get around some of thee restrictions by caching to the hard drive if it's available, and hard drive caching beats Blu-ray drive streaming hands down (a lot of PS3 games do this too - in fact, a lot MORE PS3 games do this, which is how come so many PS3 games use mandatory or optional installs).


Icemage

[Malacite]

Re: SPU-Based Deferred Shading in BATTLEFIELD 3 for Playstation 3

Ah, thankies.


Still disappointed at PS3 having so many of it's promised features cut out, but at $840 I can't exactly blame Sony (except for over-selling the damned thing)