DirectX 10 Only On Vista

Next Generation is reporting that DirectX 10 will only be released for Windows Vista. Those of us puttering along with XP will have to make do with 9. From the article: "The exclusivity of DirectX 10 means that in order to enjoy the high-end features of next-generation GPUs, gamers will need to adopt Vista. Some end users are upset with Microsoft, as the move effectively forces gamers to buy Vista if they do intend to remain serious about cutting-edge PC gaming." It may even be worth it for titles like Crysis.

Comments

Re:Of course.

[WalterGR]

I can't figure out whether people actually believe the "Vista is just XP with a new skin" /. meme, or they just propagate it for mod points...

Either way, our friend Wikipedia has plenty of information about the new features in Vista. In particular, note the following:

D3D10 functionality will require the Advanced VDDM (Vista Display Driver Model), which in turn will require new graphics hardware. The graphics hardware will be pre-emptive multithreaded, to allow multiple threads use the GPU in turns. It will also provide paging of the graphics memory.

The Direct3D page has more information.

Old News

[throx]

Microsoft has been saying DX10 would be Vista only for about a year now. I even blogged about it last September. If the gaming community is only just realizing it then they only have themselves to blame because they're a year behind the devlopment community.

There's actually very good technical reasons it can't be back-ported to XP and that's because it's changing the entire paradigm of the way the Windows OS works with the video card. The GPU and video RAM are being treated as OS resources that are time shared and paged in and out in exactly the same way the CPU and main system memory are currently. Simply put, this means at the very basic level that the driver interface (WVDDM) for the video cards is very different, and much thinner but as it is a new driver model, XP won't be able to load it.

So, game development companies are left with the decisions of whether to use DX10 which has a bunch of new features (general purpose geometry shaders that can create and destroy primitives in the pipeline), or maximize compatibility and shoot for DX9 which is being effectively frozen.

The bigger issue for most is that OpenGL becomes a "second class citizen" on Vista as any use of it outside full screen rendering effectively turns off the entire Aero interface. Users are going to notice this, and apps using OpenGL will get bad feedback for "breaking the interface when they run".

There is a legitimate reason for this.

[The MAZZTer]

Vista's new Display Driver Model. It allows for a hardware accellerated desktop environment, in addition to multiple hardware accellerated windows (ie two videos can both be playing hardware accellerated at once) and the ability for GFX cards to have virtual memory.

DX10 is built to take advantage of these new improvements. If they backported it, they'd have to do one of the following:

- Don't take advantage of the new DDM in Vista, and just do an incremental update.
- Backport the entire DDM to XP. This will result in less reasons to buy Vista anyways.

Option 1 was clearly unacceptable if MS wanted to make advancements in PC gaming software tech (stuff). Option 2 is clearly unacceptable from a business standpoint.