Inviting you to the Preview Program

I wish there was a way to virtually rub the noses of everyone who said it was impossible to emulate the Xbox 360 on the Xbox One because there wasn't enough power and that you needed a system much more powerful than what the Xbox One was, when I said it was possible and Microsoft could do it because they new how both the old and new system worked.

Sweet deal man! Thanks so much, pbroy! :D :D :D

Gonna try to play Toy Soliders tomorrow! I'm so excited for this!!

Some Quake 3 era shooters, some N64 games, and a bunch of puzzle and party games. Eg: nothing huge or demanding.

It's pretty clear to anyone who knows anything about hardware and software that emulating a system as powerful and bleeding edge on their launch like PS3 or 360 on a PS4 or XBone is extremely improbable. JIT cross compilers from PPC to IA64 and HLE of DX API calls will make it somewhat easier but still.

It's no surprise that none of the games in that list are outstanding in any technical capacity. A couple puzzle games and N64 platformers aren't exactly Bioshock Infinite or GTAV. Anyone thinking their favorite AAA games from 360 are eventually going to be supported on XBone through BC are going to be sorely mistaken.These big titles are going to require you to keep your 360 or rely on native XBone HD remasters.

See my last post above.  A couple first gen puzzle games and N64 games don't prove that this can be done.  The 360 and PS3 were very powerful for their launch.  Trying to emulate more than a couple puzzle and party games isn't going to go over very well.

Anything can be emulated, but in this context, the desire is REAL TIME emulation with performance equal to or exceeding running the same executable on it's native platform, and that is the important part.  Who is going to care about backward compatibility if they emulated version is choppy and runs 15 fps on the XBOne?

Let me know when they have 360 versions of Bioshock Infinite, Crysis, BF4, Tomb Raider, Borderlands, etc running on XBone just as well as they run on a native 360.  Some of these have native HD ports on XBone but my point is not every game as demanding as these types of titles is going to have an HD port and for those I promise you are better off keeping your 360.

The PS2 had native PS1 hardware on board and STILL fucked up some PS1 games and we saw how PS3 couldn't run PS2 games in software for all their talk about how powerful Cell was supposed to be.

General rule of thumb is you need 10 times the resources of the system you are emulating on the host to get 100% emulation speed. 

As with PS3 with PS2 emulation after they droped EE+GS hardware, if and when it DOES work, it will NOT be legit emulation, it will ONLY be the supported by the handful of games that MS and third parties invest the time into rewriting the executable for native XBox which the "emulator" will download as a "emulator enabling patch" and only use the original 360 image for assets.

<-- assembly programmer and has written a 6502 CPU core and even simple script compilers and virtual machines, have worked with GBA (ARM7), NES (6502), SNES (65816), Dreamcast (SH4), PS2 (MIPS+VU), PC (x86), and Gamecube (PPC).

MS will have a easier time at it than Sony did due to the more standard unified memory architecture and standard DX API, but we are still talking 3 core 3.2 GHz PPC vs a 8 core 1.7 GHz x86-64.  That's pretty rough.  Sure clock speeds aren't equal since the PPC were stripped dumb cores with no out of order scheduling, complex branch prediction, cache, etc like modern x86 CPUS (all omitted in order to fit the 3 PPC cores on the die size at the time, remember PCs were still single core when 360+PS3 launched).  But real time emulation/translation will still be challenging if not impossible for anything that utilized the 3 x PPC cores 100%.

GPU API calls will be relatively simple to hook (see N64 Ultra HLE concept) but anything maxing out the PPC isn't going to run the same on the x86 without recompiling and manual intervention (eg: the "emulator" just being a collection of selected 360 games rewritten by hand for native XBone)

But then MS hasn't called it emulation, they just called it backward compatibility, and it will mostly be achieved for the specific games they select that they deem are worth the investment of rewriting the binary from ground up in a native XBone binary.  In other words, yes, in fact, 8th gen systems are not powerful enough to literarlly emulate (eg: real time translation at the same performance level as native) 7th gen systems.

The biggest improvement for PS4 and XBone is GPU and RAM.  CPUs in both systems are more side grades in performance and focused on low power/noise and speed of porting and development (everybody knows x86 and PC development kits are x86).  If you think the mobile x86 CPUs in the PS4/XBOne could emulate Cell or Xenon full speed then you seriously underestimate how powerful and bleeding edge these CPUs were on their launch and seriously over estimate the bump in CPU performance of a couple of low range mobile AMD x86 processors that were outdated when the PS4/XBO were even announced on paper.  When 7th gen came out their CPUs were more powerful than anything you could get in a PC.  8th gen CPUs were never more than low range low power mobile chips even 5+ years ago in the PC world.  Huge difference.  To put it into perspective, if they were as aggressive with CPU in 8th gen as they were with 7th gen, PS4 and XBO should both have 16 core 4 Ghz Core i7 Extreme CPUs with hyperthreading, something you cannot get in a desktop PC right now.

The drive for 8th gen wasn't CPU.  It was GPU and mostly RAM.  360 and PS3 CPUs are still plenty powerful, but most associate them looking like shit because you cannot do 1080p with their GPUs and it would look like shit with only 256 MB of VRAM (reason 7th gen games look like sub 720p play doh or shiny plastic vs 8th gen) , yet emulation is nearly all about CPU.

I highly doubt that Lost Odyssey will show up on the first 100 plus games once they expand it but hopefully at least Alan Wake or Dead Rising will make it.

This is such an awesome feature. If Sony doesn't do it, I'm gonna call BS.

http://youtu.be/8a1pVbl8Sng

Idk how t embed videos but borderlands running

Impressive, especially that it's supposedly a native 360 binary running through a virtual machine, but it's just looking at the ground shooting a couple skags.  Is it going to perform as well side by side next to a native 360 in more resource intensive scenes?

Mind you I have all my old consoles and won't even play PS1 games on PS2 anymore after I noticed how bad Final Fantasy 7 and Xenogears plays on a PS2 (the roller coaster in FF7 and even the title credits stutter horribly on the PS2, and this is just a JRPG not some fast paced twitch reflex game).  I'm very picky when comparing emulated versions to the real time.  It better be perfect 100% of the time or I'm playing on my 360 instead. 

If it's truely an emulator / virtual machine like they say, this is going to come down to

1) how well games adhere to API (API calls can be intercepted and redirected and parameters passed to the native API, very fast and easily avoids the need to literally emulate at the machine level)

2) how well the JIT cross assembler works with the remaining CPU dependent code and high CPU load Xenon code converting and caching to x86.

I've never programmed on 360.  If they required strict use of API / common libraries / SDK for all 360 games and didn't allow direct hardware access and custom programming, even complex math or common algorithms and theading support provided by SDK, then they are going to have a far easier time at pulling this off than Sony ever would.  At that point there isn't much actual emulation going on except for basic logic and glue code, you are just abstracting the API calls.

One thing Microsoft has always been good with are SDKs.  Anyone remember MSDN?