Xbox 360 backwards compatibility coming to Xbox One

Compatible disc-based and downloadable games won't need to be re-purchased.

Read the whole story

 

[salamanderjuice]

Danrarbc[/url]":1x8i056f]

yeahreally[/url]":1x8i056f]From what I understand, the Xbox OS and games run as virtual machines under a hypervisor. It's possible that they've got a guest image that allows 360 games to run on the hypervisor. I always wondered if they would use that for allowing backwards compatibility with the next generation of hardware, but I didn't think they'd do it with this past generation.

They're doing the same thing they did for original Xbox games on 360. It isn't a compatibility layer, MS just isn't using the binaries on the disc or in the download and is using a special one created for the new system. This is why it doesn't work for every game.

gijames1225[/url]":1x8i056f]Very smart, they're going where Sony can't follow. This may actually make my buy a Xbox One this Fall instead of a PS4 like I was planning to.

There's no reason Sony can't do this too. It isn't emulation so CELL isn't an issue.

You're right about this but for Xbox 360 Backwards compatibility it actually was an emulator. Games need their own specific tweaks to work but it still read and used the assets off the disk. I hope Sony does something similar and at least gets PS1 classics on PS4 already.

 

[salamanderjuice]

Danrarbc[/url]":17p6n5xx]

salamanderjuice[/url]":17p6n5xx]

Danrarbc[/url]":17p6n5xx]

yeahreally[/url]":17p6n5xx]From what I understand, the Xbox OS and games run as virtual machines under a hypervisor. It's possible that they've got a guest image that allows 360 games to run on the hypervisor. I always wondered if they would use that for allowing backwards compatibility with the next generation of hardware, but I didn't think they'd do it with this past generation.

They're doing the same thing they did for original Xbox games on 360. It isn't a compatibility layer, MS just isn't using the binaries on the disc or in the download and is using a special one created for the new system. This is why it doesn't work for every game.

gijames1225[/url]":17p6n5xx]Very smart, they're going where Sony can't follow. This may actually make my buy a Xbox One this Fall instead of a PS4 like I was planning to.

There's no reason Sony can't do this too. It isn't emulation so CELL isn't an issue.

You're right about this but for Xbox 360 Backwards compatibility it actually was an emulator. Games need their own specific tweaks to work but it still read and used the assets off the disk. I hope Sony does something similar and at least gets PS1 classics on PS4 already.

Using disc assets doesn't make something an emulator. And emulator runs unmodified binaries on a new platform, which Xbox 360 BC certainly wasn't. Sounds like this is also using assets off the disc if you have a disc, just saving them to the hard drive.

How was it not? Do you have proof of this? Yes every game had a profile but most emulators do this or something similar too as some games require different tweaks to run properly than other games. It doesn't download the binary for every game sans assets.

They also said you have to download the entire game even if you own disc and it's just using it for verification. That sounds to me like they are recompiling the entire thing.

 

[salamanderjuice]

HungryBadger[/url]":wtzjlmjk]

RStormy[/url]":wtzjlmjk]

dfjdejulio[/url]":wtzjlmjk]
If the XB1/360 backwards compatibility involves downloading modified versions of the original game, like with some (or all!) PowerPC routines replaced with x64 routines, well, there are those who would regard doing that without explicit permission as a copyright violation.

I doubt it's doing that. It would be a huge effort to make any game work because you can't just copy paste out processor specific routines. Microsoft said all they needed was permission and nothing else from the devs, so it would be impossible to alter the source like that if literally nothing else is required. I'd wager a large amount of source is straight up missing too.

I bet you have to download the game into the XBox360 virtual machine either through Live or installing it off the disc. Hence the "Download" requirement.

Copyright won't be an issue, since Microsoft have stated games will only appear if the publisher agrees - hopefully the fact it's "zero effort" at that point will be enough to persuade most to just say yes.

And they wouldn't need source code, just run the entire PPC binary through a direct assembly level translation to x86. It'd be a bit of a performance hit, but not necessarily much and the improved performance of the hardware should cover the gap. The biggest issue would be the compute power necessary to actually translate every title out there, but they have Azure for that.

Sadly zero effort has still resulted in some publishers not releasing things. Putting a PS1 classic on PSN is zero effort as all the publisher has to do is give the okay, yet Konami didn't put Suikoden 2 on PSN for years because they felt it wouldn't sell.