Carmack: Rage runs faster on Xbox 360

[Procrastinato]

Squilliam said:

Procrastinato said:

If it weren't for the fact that engines mature over the course of a generation, and that the PS3 (this only my opinion ;) has much more room for growth at 3 years into its lifespan than the 360 has at 4... I would agree with you.

However, as time marches on, the 360 looks less and less appealing, since there's more potential on the PS3.  The odd thing is that, when comparing the platforms, people like to compare the CPUs and GPUs to back their claims... however, in my opinion, it is the lack of a guaranteed HDD on the 360 (for fast streaming -- comparing the BD and DVD is pointless when you look at the speed of the HDD), as well as more minor performance and optical disc space limitations, that will hold late-generation games back on the 360.

You are correct in that, early in the generation, development costs and time held PS3 games back, relative to 360 titles.  I believe we have, more or less, reached the midway point, however.  Games that are heavily dependant on animation (sports, like Madden, etc.) are now held back by the relative weakness of the Xenon, to the Cell.  Games which require fast streaming for seamless huge worlds -- again held back by use of a DVD vs a HDD.

I believe Carmack's latest engine tech will eventually reach a point where the HDD of the PS3 yields substantial gains over what the 360's DVD drive provides, and that the PS3 may very well provide a much-closer-to-PC experience than the 360 will.  Carmack himself has gone on and on about how Rage's streaming tech is its greatest feature... and unless they are intentionally avoiding using the HDD (to avoid large installs), I don't see the PS3 version being slow for very long, relative to its 360 cousin.

/1. According to id, Rage requires a lot of fragment processing power for its implementation of virtual texturing.
2. RSX has separate and fixed capabilities (numbers of shader units) for vertex and for fragment processing, which is enough for most games but problematic for Rage.
3. Xenos has unified shaders which can all be used for fragment processing if there's a need, so it can cope with the workload in Rage a lot better.' Link

I think that sums what is known about the engine pretty well. When it comes to shader heavy code or code which has a lot of complicated shaders the Xenos GPU does shine, which is likely why they are having problems now. This isn't your typical implementation of a game engine.

It really depends on what you're trying to do in a game which determines which system you want to throw your wrench at. Say for instance the Xbox 360 takes a few more ms to run the animations, doesn't mean that the time can't be made up elsewhere and for the build to reach frame target for both systems.

I know that the lack of a HDD for the Xbox 360 can be a pain in the butt. TBH it was probably a deliberate stab by Microsoft at the fact that the PS3 had a slower reading BR drive and a compulsary HDD, they may have taken it out so that Sony couldn't use theirs and their advantages for anything aside from multiplat games.

You're manufacturing a rendering scenario which doesn't necessarily exist, Squill, with the fragment shaders argument -- but it seems as though you probably understand that.

You could use all the Xenos pipes as fragment shaders, sure, but vert processing requires some pipes, in every scenario, and in many scenarios, requires a lot of them, especially with the Xenon CPU's relative lack of mathematical muscle, compared to the Cell.

Good terrain has a ton of verts.  Skinned characters take a ton of vert processing power, which either require a lot of math horsepower on the CPU, or a lot of vert pipes.  I don't imagine you are suggesting that Rage has neither, or skimps excessively on either, in order to use more than the ~27 pipelines necessary to outperform the RSX's raw fragment shader horsepower, or that it only renders at the 630p (or whatever it is) necessary in order to really take advantage of the smallish (but fast) 10MB EDRAM of the Xenos, without resorting to tiled rendering, etc?

The rendering situation is, always, very complicated, just as you are stating.  You only get to use flexible pipes for fragment shading ops when you aren't using them for vertex ops.. The Xenos being "more powerful" than the RSX is very very app- and workload-dependant, and in many cases, only mildly comes into play, if at all.  The HDD vs DVD streaming could be a much bigger deal, going on Carmack's statements about the latest iteration of his engine in previous media quips.

 

I think MS was just being financially smart, with the lack of the HDD, personally.  They're good with the accessories and the pricing schemes, making the X360 appear to cost less, at the outset, than it really is to most.  That's just a good pricing scheme at work, "easing" the users wallet into spending the money necessary to own a nice console, rather than "you want this cool thing?  You have to pay this much..." up front thing that Sony does.

In any case, I agree mostly with your statement, but I think the possibility that the PS3 version could shine, by release, is very much in the realm of possibility, especially given the attention to the streaming technology that iD's new tech relies upon, and the advantages the PS3 has in that area.