DirectX 11 in a nutshell
- — 22 October, 2009 12:19
The wait is over — Microsoft’s latest API (application programming interface), DirectX 11, has arrived on both Vista and Windows 7. With it comes a host of exciting new features for PC gamers and multimedia enthusiasts. In short, DirectX 11 enables better gaming through more realistic graphics and faster playback of multimedia files. It was developed with significant input from top graphics chip makers NVIDIA and AMD.
The DirectX 11 tools include a set of APIs for realistic images and better sound when playing games or watching movies. For example, game developers will be able to create smoother and realistic images in a game through better 3D modelling.
Here’s a brief overview of what’s new:
Better use of multi-core CPUs
Hardware Tessellation — This is the fancy word for breaking up an object made of a small number of triangles (and thus blocky-looking) into a very large number of triangles, which can then be manipulated to make the object look smoother or more detailed. Naturally, this translates to more realistic 3D objects and scenery in games.
DirectCompute (a.k.a. "Compute Shaders") — This harnesses the parallel processing capabilities of GPUs (graphics processing units) to improve gaming on PCs. These improvements could make games more realistic through faster frame rates, for example. As users demand heavier graphics from PCs, it is in Microsoft's best interests to offer an operating system that breaks up tasks across multiple graphics cores and CPUs. DirectCompute provides this functionality.
CUDA and ATI Stream — These are the parallel computing architecture systems developed by NVIDIA and AMD, respectively. CUDA is more popular, but it's still mostly stuck in the "big iron" high performance computing fields, with only a handful of real consumer apps. New programming models, such as using the GPU for general computing tasks, tend to take off when standards emerge, so the real action will probably be in OpenCL and DirectX 11 Compute Shaders.
DirectX 11 will also enable video conversion on the fly simply by dragging and dropping video from PCs to portable devices.
Microsoft's marketing department is doing its best to brand DirectX 11 as a Windows 7 thing, but the truth is that it's coming to Vista as well. That said, the DX11 graphics drivers are designed to help Windows 7 effectively break up tasks over multiple cores to boost application and graphics performance. For example, Windows 7 will process video faster by unloading the task from the CPU to graphics processor cores.
Beyond simple multimedia tasks, DirectX 11 harnesses the massive parallel processing capabilities of GPUs to improve gaming on PCs. In the words of Neal Robison, director of independent software vendor relations at AMD: "We're going to see gaming at a whole new level of realism that you've never been able to experience before because it just hasn't been possible."
While Microsoft has built native DirectX 11 support into Windows 7, users will benefit only with capable hardware. That is, while Windows 7 has built-in support for new DirectX 11 tools, you still need PC hardware that supports those tools — such as the DirectX 11–capable Sapphire ATI Radeon HD5770 graphics card, for example.
The DirectX 11 enhancements may encourage developers to build games for Windows 7 and help the Microsoft keep pace with competition. One company competing with Redmond is Apple, which has changed the basic architecture of its ‘Snow Leopard’ OS to include new features that divvy up graphics and other tasks over multiple CPU and graphics cores.