CompuDav

Hello everybody,

First of all, let me say that I think that the concept of XNA rocks, and I'm very happy that Microsoft actually released a cheap "SDK" for the 360.

Secondly, has there been a list compiled of things that are off-limits to developers All I know of that is off-limits is the networking. From what I've read, I assume that the DVD drive is out and so are any system/other game files on the 360. But I can't believe that these are the only things off-limits... I mean, can we really access everything on the 360's GPU and CPU (note that I'm not talking about every register because it isn't assembly language) I think a complete list of everything that is inaccessible would really help those on the "fringe" of purchasing XNA.

Thanks for your help, and thanks Microsoft for creating XNA!

David



Re: XNA Game Studio Express Quick question regarding accessibility of 360 hardware with XNA.

Jim Perry

You have access to all the capabilites on the GPU. I'm not sure what you mean by "access everything" other than that. XNA games only run on one of the CPUs but that hasn't proven to be a problem from what I've seen. No one is going to be doing Half Life 3 or Doom 4 so that restriction won't hurt. You have access to space on the HD for your save games and such. Basically except for networking you should be able to do whatever you need to do for your game.




Re: XNA Game Studio Express Quick question regarding accessibility of 360 hardware with XNA.

CompuDav

Jim Perry wrote:
You have access to all the capabilites on the GPU. I'm not sure what you mean by "access everything" other than that. XNA games only run on one of the CPUs but that hasn't proven to be a problem from what I've seen. No one is going to be doing Half Life 3 or Doom 4 so that restriction won't hurt. You have access to space on the HD for your save games and such. Basically except for networking you should be able to do whatever you need to do for your game.

Thanks for your response!

Hmmm... I was under the impression that you could use multiple cores with XNA using threading. So does that mean then that if I were to create a multi-threaded game on Windows, it would have to be reduced to a single thread if I were to deploy it to the 360

You're quite correct that nobody using GSE is doing the next Doom or the next Flight Simulator even, but this thread is purely for curiousity :). I'm trying to understand how close to the real 360 dev kit the XNA platform is (e.g. we all know that Sony's restricted GPU access on their console, but I'm trying to figure out what Microsoft has restricted).

David





Re: XNA Game Studio Express Quick question regarding accessibility of 360 hardware with XNA.

Jim Perry

Hmm, there is the Thread.SetProcessorAffinity method. Maybe I was thinking of Windows game, since it's stated that this is available only on the 360.  Hard to keep track of everything.




Re: XNA Game Studio Express Quick question regarding accessibility of 360 hardware with XNA.

Jon Watte

You have threading both on Windows and 360. The difference is that you go through a different API on Windows than on 360 -- on 360, the thread itself has to set its affinity; on Windows, you use the full .NET 2.0 framework System.Threading API.






Re: XNA Game Studio Express Quick question regarding accessibility of 360 hardware with XNA.

DeanoCalver

Not all the capabilities of the GPU are supported. I believe its been stated that memexport isn't, which is kind obvious cos it would leave a whacking great security hole in the managed run-time.






Re: XNA Game Studio Express Quick question regarding accessibility of 360 hardware with XNA.

maddogjt

Along with memexport, there are several other GPU features that are not available through XNA (vfetch, vertex tesselator, XPS).




Re: XNA Game Studio Express Quick question regarding accessibility of 360 hardware with XNA.

CompuDav

maddogjt wrote:
Along with memexport, there are several other GPU features that are not available through XNA (vfetch, vertex tesselator, XPS).

Once again, thanks to everyone for their responses!

Am I correct to assume that these features of the GPU are extremely advanced and would not be relevant to most games

So basically I'm getting the impression that XNA is powerful enough for most games (i.e. all of the Live arcade games, and probably a decent amount of 360 commercial games), but it isn't powerful enough for a Doom 4, for example, because it would probably need to take advantage of the additional GPU features in order to achieve maximum frame rates.

At the end of all this, I just have to say: Damn XNA is exciting!





Re: XNA Game Studio Express Quick question regarding accessibility of 360 hardware with XNA.

Shawn Hargreaves - MSFT

vfetch is actually available in XNA. We haven't yet released any docs explaining how to use this though :-(

You're right that the vertex tesselator is not currently exposed.





Re: XNA Game Studio Express Quick question regarding accessibility of 360 hardware with XNA.

ricodued

While this isn't hardware related, I don't think it merits it's own thread:

Do we, or will we, have access to the 360's on-screen keyboard and save-location dialogs, etc.