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Have you wondered what all the hype around Microsoft Windows 7 and DirectX 11 is all about? We will shed some light and answer some of those questions in this blog.

Let’s start with Windows7, everyone, including my own mother, is talking about this amazing operating system. Microsoft is rumoured to be launching the successor to Windows Vista in late October. What does it mean to you the PC user?

I cover my experience with Windows 7 in this blog; in a nutshell, the experience has been fantastic. It seems that Microsoft has worked out all the kinks and quirkiness of Windows Vista and are about to launch an incredible OS for the PC. Windows 7 (when compared to Windows Vista) is designed to offer the user a much more refined experience, smaller footprint, faster response times, long battery life and a much more visually intense and enjoyable PC experience.

Wrapped up in all the new Windows 7 OS splendour is a new API (Application programming Interface) called DirectX 11. Basically, the API allows developers to program software that uses a standard set of terms to communicate with the libraries and the OS. Think of it as game developers have some new toys to play with inside Windows to allow them to deliver better software.

DirectX has been around since 1995 with the launch of Windows95, a full history can be found here.

Let me break down the features and benefits of DirectX 11 -- the main features being:
-Tessellation  -- Multithreaded Rendering  - DirectCompute

Tessellation is a technology that has been around for a few GPU (graphics processing unit) generations. AMD has had Tessellation support since 2001, which was then called Truform; we also implemented Tessellation in the XBOX 360 GPU, then codenamed “Xenos”. Tessellation is a feature which increases the number of polygons in an image. Basically, Tessellation enables a more lifelike image, both of objects and landscape. Back in the day characters who were CG (computer generated) looked very blocky, almost cartoon like; with the use of Tessellation, developers are now able to significantly increase the number of triangles to draw an image, thus creating a more lifelike quality in games.

Multithreaded Rendering is a feature which allows DirectX to be processed via multiple CPU threads. This means that a dual-, triple- or quad-core CPU can have a higher utilization across all cores than DirectX APIs in the past. Historically the OS would load up a single core for commands to the GPU, in essence creating an overload on the first core and under utilizing the additional cores. With only one core issuing commands to a GPU, we have seen CPUs hold back the potential performance of the GPU. With Multithreaded Rendering, DirectX will take better advantage of all the available cores. This should result in a better experience for the multi-core user because of a faster processing pipeline and increased scaling.

DirectCompute is a feature which allows access to the shader cores/pipeline for Stream Computing (graphics acceleration) type applications and physics acceleration. One of the biggest technology breakthroughs of the past 5 years has been the notion that processing can be moved from the traditional CPU to the much more parallel GPU. Simply put, the CPU manages tasks sequentially; it accomplishes a task then moves on to the next task in a very orderly fashion and with tremendous speed. Today’s CPUs can work at speeds of up to 108.8 GigaFLOPS (Floatingpoint Operations Per Second).

A GPU is designed to work with many slower cores in parallel, giving a much wider vector -meaning a wider road for more cars to travel on -- than a CPU. This allows tasks to be completed faster if the program or software is developed to take advantage of many-many cores, albeit slower ones. Today’s GPUs can work at speeds up to 1.36 TeraFLOPS, giving the GPU a significant (almost 11 times faster) advantage when the proper software is run. This advantage truly delivers on the processing capabilities of Stream Computing. DirectCompute allows easier access to the GPU’s many cores for parallel processing; if the user is running applications that take advantage of Stream Computing then the performance experience increases considerably. We are seeing transcoding as the first type of task that is seeing tremendous benefit using Stream Computing. This means if you are an avid HD video or music user you will benefit when converting files to play on your laptop or iPod type devise; Stream Computing can significantly cut down the wait-time for enjoying your converted media.

Now, if you are a gamer you undoubtedly will be asking me “What games are going to support DirectX 11″? This is always a tightrope to walk for us as we are unable to pre-announce our technology partners titles and the specs around those titles; still, we want to give the consumer confidence that we’ve been assured there will be substantial titles in the market that take full advantage of your ATI Radeon DirectX 11-compliant graphics card. So, as this blog is published, here are the future DirectX 11 games we can talk about:

Dirt2 by Codemasters
BattleForge by EA
S.T.A.L.K.E.R: Call of Pripyat by GSC Game World

- Check out this early spoiler for Dirt 2 -

Some industry folks have stated that we will see more titles that support DirectX 11 then we did for DirectX 10. Some even say that DirectX 11 is the full implementation of what DX10 should and could have been, but that is subjective opinion and conjecture.

Game developers discuss the benefits of DirectX11

Windows7 and DirectX11 are right around the corner, as is the newest ATI Radeon family of graphics cards. As always, it’s our goal to blur the lines between reality and what is rendered. I believe we have made a major leap towards crossing that chasm with our ATI RadeonTM HD 5000 series products and their support for DirectX 11.

Tessellation - Minimized

With Tessellation - Maximized!

Between now and the launch of Windows 7 and DirectX 11, we will continue to uncover the technical details, as well as the visual implications, for the user experience.

At the time of this blog, AMD will be the first GPU vendor to market with a fully compliant and enabled DirectX 11 graphics product. So don’t be fooled by claims in the market about DX10 GPU’s supporting DirectX 11….

My good friend Tim Smalley from bit-tech.net has a great in-depth article on DirectX 11: A look at what’s coming – Check it out.

Cheers!

Ian “Cabrtosr” McNaughton

Ian McNaughton is senior manager of advanced marketing at AMD. His postings are his own opinions and may not represent AMD’s positions, strategies or opinions. Links to third party sites are provided for convenience and unless explicitly stated, AMD is not responsible for the contents of such linked sites and no endorsement is implied.

Microsoft, and those of us in the graphics business, have been openly talking about DirectX 11 for around a year now – in fact, to be honest we’ve been talking about it since even before Windows Vista shipped at the very end of 2006!  It takes a long time to put together a new version of DirectX and there are often tough decisions about what to leave out while finalizing any one version.  So we often agree that the parts which are being left out in the ‘current’ version will find their way into the next version. 

So let’s take a good look at what’s in DirectX 11.  I’m not going to go into painful technical detail; instead, I will try to look at the consequences of those technical details.  One important note, unlike DirectX 10, DirectX 11 isn’t tied to Windows 7, so those of you sporting a Windows Vista system will get to reap the rewards as well.

There are three main areas of impact in DirectX 11:

1.  A beast called the tessellator has been added which enables games developers to create smoother, less blocky and more organic looking objects in games. This is the change you’ll probably be most aware of. And it’ll show up when you look at the silhouettes of hills and mountains or the profiles of characters in games. Where artists previously had to trade off quality for performance, now artists will have the freedom to create naturalistic scenery. We’ve gotten used to seeing strangely blocky ears and noses on our opponents. But the new generation of games should allow those opponents to scare the heck out of us instead. The tessellator represents a natural next step in gaming hardware (in fact the Xbox 360 graphics chip that AMD designed already has a tessellator, and AMD graphics hardware has featured tessellator technology starting with the ATI Radeon^TM HD 2000 series right up to the latest ATI Radeon^TM HD 4000 series cards today).

[An example of tessellation giving characters more definition.]

2.  Games programmers will also be given a radically new way to program for AMD graphics chips. The second new beast in the menagerie is the excitingly named “Compute Shader”. It allows games programmers to treat the GPU in a much less graphics-oriented way; indeed, they can almost treat it like a highly parallel CPU. [The buzzword for this is "GPGPU" , see http://blogs.amd.com/play/2008/11/05/the-gpgpu-chronicles/ for details.]

Up until DirectX 10.1 a graphics programmer always had to think in terms of triangles – but the compute shader changes that and allows the programmer a much freer expression of their thoughts.  If you try to solve a problem of artificial intelligence or physics, you probably don’t think the problem through in terms of triangles.  So the compute shader is a more natural way for the programmer to approach his or her task.  On top of that it allows access to some of the features that would otherwise have been hidden away inside our present and future chips and for that reason it will often allow significantly more efficient implementations than heretofore (that means “higher frame rates” to you and me ).

3.  DirectX has been sliced and diced and the internals redesigned to ensure that it is much more efficient at using the horsepower present in multiple CPU cores. This will be a huge win on chips like our AMD Phenom^TM II quad and triple core processors [http://www.amd.com/gb-uk/Processors/ProductInformation/0,,30_118_15331_15332,00.html] and it will provide the opportunity for both higher frame rates and games which are more realistic, because they contain dramatically more detail.

There are numerous other, less important changes aimed to make the games programmer’s tasks easier.  Some so small that you’d have to be a games programmer to care, some (like improved texture compression) are big enough to help out significantly with performance in corner cases.

Quite often you get to hear rather bland but optimistic statements about the future versions of DirectX.  “It’ll be faster and better” – but you don’t get to hear much in the way of substantial justification.

This time around I hope it’s abundantly clear – I predict that:

• We’ll see higher frame rates because the way DirectX 11 uses CPUs will be more efficient.
• We’ll see higher frame rates because games developers will be able to use our GPUs more like CPUs.
• We’ll see smoother, more realistic characters and more realistic terrain as we move away from blocky polygonal representations to the kind that are used in movies.
• And a side-benefit, that will help PC gaming generally, is that the new version is easier to use, so it will help to keep game development costs down.

On top of that there’s something worth mentioning here about the evolution of computer graphics.  Every generation of DirectX has been designed to be an improvement upon the previous generation.  We always make a point of including all the old functionality (so that you can run any of your existing games).  This time is no exception; the nearest thing to DirectX11 is DirectX10.1.  And it won’t come as a surprise to anyone that I can’t resist mentioning that this means that owners of ATI Radeon^TM HD 4000 series graphics have a distinct advantage, since AMD is the only major supplier of graphics chips that supports DirectX 10.1 http://ati.amd.com/products/Radeonhd4800/index.html .  DirectX 10.1 is the closest you can get to DirectX 11 until Windows 7 ships.

When it does ship though, get ready for a significantly improved gaming experience thanks to the combination of DirectX 11 features enabled by phenomenal new DirectX 11 hardware from AMD.

Richard Huddy is Sr. Manager Developer Relations at AMD. His postings are his own opinions and may not represent AMD’s positions, strategies or opinions. Links to third party sites are provided for convenience and unless explicitly stated, AMD is not responsible for the contents of such linked sites and no endorsement is implied.