The Straight Story: DirectX 10.1

[Astrotoy7]

OK. Any of you techeads with a passing interest in graphical processing hardware and software will have heard the rumblings about DX10.1.

 

MS Direct3D team has recently unveiled further details at the annual SIGGGRAPH(Special Interest Group for Computer GRAPHics) conference.

 

Here's some of the presentation content with some further tech details... There is also a great article at elitebastards

 

but a basic summary can be as follows:

*DX 10.1 is a revision of the DX10 API. MS announced that it plans quarterly point revisions of DX10.

*DX 10.1 will introduce pixel shader 4.1 and WDDM 2.1(the latter being windows encapsulated drivers)

*The DX10.1 SDK preview is availabe for MS TechNet subscribers to have a looksee. Though theres not much they can do with it without DX10.1 compliant kit or SP1

*The DX10.1 SDK and hardware will require Vista Service Pack 1 but can service DX10 and 10.1 apps/hardware. ie. it wont be dx10.1 specific

*Introduces the long awaited shift from DirectSound to XA2(Xaudio2). A few of you may know this is the same standard used by the x360. This has been done to improve cross platform development between PC an x360 > which fits in with Windows Live and Xbox Live's integration infrastructure

 

Now, the interesting bit:

*Current DX10 hardware devices will *NOT* support DX10.1 Functionalities.

 

Now, there is more to this than "OMG! MY DX10 CARD NOW SUX!!" which has been the initial reaction to this(including mine for a couple of minutes until reading further )

 

*What DX10.1 protocols will do is *mandate* performance characteristics to hardware manufacturers. Ever wondered why the ATI<insert model no> card does better/worse in benchies than the Nvdia counterpart with seemingly identical specs ??

 

This is simply because any such protocols pre DX10 did not exist. It will allow devs to make games of higher standards, without the comptability and worries across the range of cards circulating on the market. If a game is made with DX10.1 an you have DX10.1 hardware, then this means you have certain functionalitiy built in as a minimum, which did not exist in DX9. eg. ATI an nvidia cards that has similar specs often worked off different shading models(which was a nightmare for devs to code for)

 

Heres a slice from the elitebastards article which adresses tech issues that will mean the most to gamers:

 

Firstly, this revision of the API will see the introduction of 32-bit floating-point filtering over the 16-bit filtering currently on show in DirectX 9 and 10 - This should see improvements to the quality of High Dynamic Range rendering which use this functionality over what is currently available.

 

On top of this, overall precision throughout the rendering pipeline will also be increased, although to what level doesn't seem to have been publically specified at present.

 

...DirectX 10.1 will also see the introduction of full application control over anti-aliasing. This will allow applications to control the usage of both multi-sample and super-sample anti-aliasing, as well as giving them the ability to choose sample patterns to best suit the rendering scenario in a particular scene or title.

 

Finally, these changes in DirectX 10.1 give the application control over the pixel coverage mask, a mask which is used to help to quickly approximate sampling for an area of pixels. This in particular should prove to be a boon when anti-aliasing particles, vegetation, scenes with motion blur and the like.

 

All of this additional control handed to the application could allow for anti-aliasing to be used much more wisely and effectively, and controlled by game developers themselves, rather than the current 'all or nothing' implementation available, which basically amounts to a simple on-off switch.

 

To add further to the additional focus on anti-aliasing in DirectX 10.1, support for a minimum of four samples per pixel (in other words, 4x anti-aliasing) is now required (Although this doesn't necessarily mean that support for 2x anti-aliasing in hardware and drivers is a thing of the past)

 

So for those who have a DX10 card, or are contemplating a DX10 card the the G80 from the R600 series. Should you wait ??

 

Whilst there have been no firm announcements, there is currently no production level work being done by nvidia or AMD. With the August SDK preview just having been released, it is definitely very early days. Add to this the fact that Vista Sp1 also has not been released yet(though not too far away)

 

Devs are still *really* catching up on DX10 alone, with a hardly solid foundation of apps and titles to be established, making planning a DX10.1 purchase still a bit premature.

 

Speaking of premature, the final and most important consideration when dealing with graphics hardware.....drivers. With DX10 drivers gently edging towards a semblance of functionality(SLI was only enabled in G80 in Vista as recently as March 2007) the timeframe involved from R&D>testing>SDK deployment>Release to the drooling tech head masses is signficant,

 

In a years time, when G80 and R600 drivers will be comig into their element, the 10.1 compliant series will be meandering through its formative processes. By then, there will of course be at least 2 point revisions to DX10...although it hasnt been stated clearly if further revisions will create exclusive functionalities for each generation of hardware.

 

The best course of action is to decide what you want to play and what level of performance you want. Then look up some benchies and see what your best options are, relative to the size of your wallet. With the amazing benches posted by the likes of 8800GTX, I would gladly take one now!!

 

I guess it's just a reality of tech and computing sucks on the bank balance too !

 

mtfbwya

[tk102]

Great information Astro. With all the application-level control that DX10.1 will provide, it sounds like competent DX10.1 programmers are going to be in high demand in the gaming industry. I'm sure Bethesda can't wait.

[stingerhs]

yeah, i was a bit ticked when i first heard that my 8800 GTS was already outdated for the next version of DX10. good thing is that DX10.1 won't be hitting the market for a while, so that makes me breathe easier.

 

and seriously, thanks for consolidating all the info down to one post. i've only heard some spatterings here and there on the web.

[Q]

Great post, Astro!

 

I was afraid that something like this was going to happen. I'm beginning to believe that DX10 compatibility is practically irrelevant for the time being. Those building or upgrading right now would probably be better off buying a cheap high-end DX9 card and waiting until the dust settles. Most DX10 games will be backward compatible with DX9 for some time to come anyway. The sub-$200 X1950XT is probably the best bang for the buck right now. Negative Sun, our resident ATI fanboy, will probably like the sound of that.

[Astrotoy7]

Great post, Astro!

 

I was afraid that something like this was going to happen. I'm beginning to believe that DX10 compatibility is practically irrelevant for the time being. Those building or upgrading right now would probably be better off buying a cheap high-end DX9 card and waiting until the dust settles. Most DX10 games will be backward compatible with DX9 for some time to come anyway. The sub-$200 X1950XT is probably the best bang for the buck right now. Negative Sun, our resident ATI fanboy, will probably like the sound of that.

 

Thats great advice for most people Q, especially those on a budget.

 

Of course I will seem somwhat biased being an owner of an 8800GTS, but for someone with a monitor supporting 2560x1600, no 7 series card would have cut it for me...I sold my 7950GX2 simply for this alone. I intend to game at 1600x1200 and beyond and my shuttle case only has room for one dual slot card

 

The advantages of Dx10 havent been discarded with 10.1, just enhanced.

 

Maybe I should do a similar summary for Dx10 in general ?

 

mtfbwya

[Q]

Not to say that those that bought a G80 or even R600 series card (well, at least the high-end models as the low-end models from both camps are pretty much crap:) ) are SOL. They outperform everything else from the previous generation in DX9 by a considerable margin, and have DX10 compatibility to boot, so the value is definitely there. Those of you with high res monitors would be crazy to buy anything else (that is, unless it's TWO x1950XTs, which would out-perform a single 8800GTS for about the same price:xp: ). I'm kind of stuck in the middle at 1680x1050, so the choice isn't so clear-cut for me. I'd probably just try to find the very best deal that I could on an 8800GTS640 and be satisfied. Then again, a cheap X1950XT would probably fit the bill for quite some time to come, with about half the sticker shock.

 

I must admit that I don't care very much for what M$ is doing here. They need to just pick a friggin' standard and go with it already!

[Negative Sun]

Great post, Astro!

 

I was afraid that something like this was going to happen. I'm beginning to believe that DX10 compatibility is practically irrelevant for the time being. Those building or upgrading right now would probably be better off buying a cheap high-end DX9 card and waiting until the dust settles. Most DX10 games will be backward compatible with DX9 for some time to come anyway. The sub-$200 X1950XT is probably the best bang for the buck right now. Negative Sun, our resident ATI fanboy, will probably like the sound of that.

Yes he does, he ain't going near DX10 until MS makes up their mind and some good games (including at least one Star Wars game) are released for it...

 

ATM I'm still stuck with a No-Pixel-Shader GeForce 4 MX 4k, so a X1950 of any kind would be a massive improvement for me already anyways.

[urluckyday]

^NegSun...I had the exact same card, and it really sucks. What do you have, the PCI or AGP version? (I was stuck w/ PCI card)...well, I hope you get a new one soon b/c that card is compatible w/ like 5 games in total...

 

Hey, good info. I'm still gonna wait for a new card, but that's cool so that I won't have to rant about it.

[Astrotoy7]

lolz... I think those who think they are going to be waiting for the 10.1 compliant card will be sore they missed out on the next few months of DX10 stuff thats going to come out, not to mention the superior performance with dx9 based games. Of course, by the time 10.1 cards hit stable drivers, 10.3 SDK will be rolled out

 

I hope this is an easier analogy

The differences rolled out in point revisions need to be noted as tweaks to a high powered engine. Whatever you do, its still a high powered engine !! The tweak on its own isnt the whole basis for its performance.

 

I cant wait for the real DX10 games to make it through.... theres a zillion now penniless gamers out there, armed with their 8800GTX's...ready to go monkey crazy when crysis comes out

 

mtfbwya

[urluckyday]

Actually...it's more because my Sony Vaio (NEVER BUY A SONY DESKTOP!!!) doesn't have any good slots to put it in...in other words...they didn't want to include a PCI-E x16 slot...so I actually wouldn't be able to use a DX10 card anyway.

[Negative Sun]

I cant wait for the real DX10 games to make it through.... theres a zillion now penniless gamers out there, armed with their 8800GTX's...ready to go monkey crazy when crysis comes out

Somewhere out there is a mega-geek living in a cardboard box with an SLI 8800GTX rig...

 

 

 

^NegSun...I had the exact same card, and it really sucks. What do you have, the PCI or AGP version? (I was stuck w/ PCI card)...well, I hope you get a new one soon b/c that card is compatible w/ like 5 games in total...

AGP, it's actually not that bad, I can play KotOR and TSL just fine, as well as Battlefront and EaW (barely though), but it's about time for an upgrade definitely...

[Astrotoy7]

Somewhere out there is a mega-geek living in a cardboard box with an SLI 8800GTX rig...

 

not as uncommon as you'd think ! Ive seen 2 in my lan travels...but they were more showcase rigs built by those rich showoffs who never actually play anything.. Looking at the 8800GTX numbers, SLI for it *really* isnt necessary, even at or beyond 1080p !!

 

mtfbwya

[Negative Sun]

I think it defeats the purpose of SLI, wasn't it developed to allow people to buy 2 mid-end cards to get max performance?

 

As long as there's no DX10 games out there, any DX10 card is practically for show, because everything else can be handled by high-end DX9 cards as well...