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Xbox 2 - The Price of Compatibility?
Randy Lastimosa writes "1UP.com has an interesting article about the next Xbox, and whether it will support current Xbox games. They talked to a number of sources and got conflicting reports. For example, the CEO of Nvidia, who provided graphics chips for the current Xbox, said: 'It's virtually impossible on many levels,' he adds. 'On an intellectual-property level. On practical levels, too.'"
If it doesn't, people will feel ripped off.
I don't know.
Look at Nintendo's consoles. They've changed formats from one generation to the next.
Obviously the PlayStation3 is not going to play xbox games, so how is it going to solve the problem for someone who wants to play old ass xbox games? The only people who will give a shit about backward compatibility are current xbox owners. And guess what they all have in common... AN XBOX. Besides the PS2, has there ever been a game console in history that was compatibile with previous generation products by the same manufacturer? Certainly not in the modern age of consoles (NES through current).
Get a grip, people. Backward compatibility means nothing except to the dozen morons here who are so stupid they have shitty jobs and can't afford a place to live that is big enough for two game consoles. Besides, who even plays old games once the new console has been out a while? Losers and idiots, that's who.
HO
'On an intellectual-property level' What does this mean? It's a computer, they can't port the games?
Well, if you think about it, most of the games won't be just writing to DirectX/Direct3D only. Most or all of the pretty engines are going to be writing (for example) shader code directly for the Nvidia GPU that is built in to the XBOX.
Since we know that XBOX++ will not contain an Nvidia GPU (they're going with ATI instead), it is pretty safe to say that using binaries compiled for the current XBOX will not work. If they did, then that would mean that the graphics chips would have to be functionally identical (or at least close enough) to the Nvidia part. Nvidia probably holds a bunch of patents surrounding the chip which currently preclude this unless MS and/or ATI wants to get sued to oblivion.
Mechanik
I just thought that I'd clear up the common misconception that there is a performance or innovation cost for including the PS2's backward compatibility. There wasn't. The PS2 contains the entirety of the PSOne hardware, PSOne games are played natively, not emulated, and the PSOne hardware controls I/O when a PS2 game is running. Because Sony already had chip fabs and such for the PSOne chips, repurposing those chips in the new system actyally saved them money. Being able to play the old games was just a benefit of this route.
Bork Bork Bork!!
The only area where I can see problems is that Xbox vertex and pixel shaders can be (and often are) compiled to nVidia's proprietary binary format (which represents a much more hardware-specific mapping than the standard DirectX hardware-agnostic binary token format). If this issue is solved, or nVidia turns a blind eye, there should be no major technical obstacles to software emulation. Legally, I think it may be OK, as the specifics of the nVidia shader format is not disclosed even in the Xbox SDK itself, so Microsoft could very well write a layer that just translates the nVidia format to whatever internal scheme ATI's silicon will use.
Other consoles, like PS2 allow much more low-level access, so compatibility via software emulation only is more of a pain.
There's 10 types of people in this world, those who understand binary and those who don't.
Nvidia is playing for the press right now. They're peeved at MS for the original Xbox deal, and now that they've been shafted for Xbox 2, they're going to try to make it as difficult as possible for MS to build backward compatability into Xbox 2. It'll happen, Nvidia will make a buck on it, and they'll tone down the criticism. Standard fare.
I know atlest 2 families where the children got PS2s for presents and the kids then went out and bought PS1 games. Two reasons:
There weren't a PS2 version available (yet?) of that must have game.
The games are cheaper and there are also lots of dirt cheap second hand stuff available which equals more games to play.
I'm sure the backward compatibility influenced their wishlists and that the kids are a lot happier with their PS2s than if they had been given xboxes.
/greger
The additional RAM and HD give the XBox the edge. Without that, the VPU would only be a teeny notch above the one in the GC.
But a game like Knights of the Old Republic would have been near-impossible to run on the meager allotment of RAM the Gamecube has and no HD to use as swap space.
The other thing to remember is that the XBox renders *everything* at 480p resolution, then downscales it to 480i before it outputs to the (standard) TV. The Gamecube renders at 480i by default unless the specific game tells it to render at 480p.
Comment of the year
Personally, I think that backwards compatibility could still be done without trampling all over nVidia...as long as they keep the hard disk or a disk-like storage mechanism.
Xbox developers are specifically prohibited from writing to the metal. For any graphics calls, sound calls, I/O calls, or any hardware call, they have to go through the API. In that way, developing on the Xbox is rather like developing against a system abstraction layer. Change the kernel but keep the entry points the same, and you should work fine. After all, most games use the vertex shaders (which are well-documented and implemented on ATI's cards), so I don't see a problem.
As for the IP issues, the only issue I can see is implementing some nVidia-specific texture formats, but since most of them were not supported or recommended by Xbox Developer Services, few (if any) games use them.
The possible flipside is that VirtualPC technology may not work on the IBM processors. VirtualPC will not work on the G5 due to the elimination of a certain addressing mode. If that addressing mode is still gone in the processors made for MS, then backwards compatibility just got 100's of times harder to implement.
RomSteady - I came, I saw, I tested. GamerTag: RomSteady / http://www.romsteady.net
I didn't really understand what nVidia was talking about when they said the games used their shading technology. Isn't that all hidden behind Direct3d?
Yes, but presumably they have some proprietary technology involved. So if Microsoft substitutes another shader, games won't look quite the same. And since designers of XBox1 games presumably optimized their titles to get the best possible results from the existing shaders, any change in shader behavior is likely to be for the worse.
No where is it written that the next XBox will play current XBox games.
According to the title the Xbox2 will play current XBox games. No where does the article provide any supporting evidence to this claim, and in fact largely runs counter to it. Nvidia says all but no, an unknown independent analyst agrees, ATI says that it is statistically possible, and some other unknown agrees with them. Microsoft says... Nothing. According to other sources Microsoft is "not guaranteeing" backwards compatibility, and if they decide not to include a hard drive such compatibility may not be possible at all.
nVidia may very well be playing to the press, but that doesn't mean such a thing wouldn't be difficult or expensive. Most systems achieve backwards compatibility by finding uses for the extra hardware. Software emulation for compatibility has never been attempted professionally in the console arena, but amature software emulation tends to lag two systems behind. You can push an XBox to do a meaningful SNES, but Dreamcast emulation is right out. With the right software the SNES could emulate the 2600, but not the NES.
Personally, I don't see why they don't just include a detachable Xbox chipset as a free add-on with an overpriced "premium" system with two controllers, and sell a regular setup with one controller for 100 dollars less.
But, as I mentioned before, no such thing has been announced yet.
The ______ Agenda
Along with the other reasons, it must be said that the XBOX was not successful enough (especially in Japan, where it counts) to need to be emulated in XBOX 2. It's a complete waste of money, if it's even possible.
Something everyone should be forced to read
Although some games do work under x86 emulation, you're right that many do not really perform all that well.
However, it's obvious why this is if you look at the two issues behind it:
VPC for PPC does not really use the Mac's video card. For versions up to VPC5 it emulates onboard shared video, and sends that to the Mac to deal with by drawing the Windows desktop inside an ordinary application window.
In fact, the video card must draw both the Mac desktop and the Windows desktop in real time. Any game that expects to see a PCI/AGP card sees only an el-cheapo PC with 4MB of onboard (shared in RAM) video.
So, right from the get-go, the emulator is not compatible with most games any more than it would be with a bare-bones PC with no video card installed and game performance would be properly compared to such a PC. Anyone who's serious about games on x86 uses a decent video card to help things along.
VPC 6 does emulate a PCI/AGP card, but again it's in emulation; the video card in the Mac is never detected as such and doesn't get the hardware calls it would with an actual x86 box. Video is processed by the PPC CPU and ordinary motherboard RAM in the emulator, then sent to the video card to be drawn onscreen.
The other issue which isn't as big a deal with XP (it's not allowed, really) but is a big deal with Win95/98 games is that many games make "sneaky" calls to the hardware to overcome various bottlenecks in Windows itself. Games who make those calls to the emulator don't find what they expect to see (not real hardware) and fail.
VPC has always been a business/productivity solution and never a game solution; Connectix's sales literature, product boxes, and web sites always said quite openly that it's not recommended as a solution for x86 gaming and game issues are not supported.