Progress is progress. We had it with DX8 and 9, so why would it be any different now? If you cannot stomach the idea that your new GFX card may be out of date soon, then you should be aware that if you have already brought a DX10 compatible card it will still be quite some time before DX10.1 is out and utilised by developers and hardware vendors, so it is likely that you will at least had a couple years use of DX10 hardware.

AMD and Nvidia have NO DX10.1 compliant hardware on the market at the moment. The additions to the DirectX 10.1 API are more varied than just purely graphical amendments. The main improvements with sound are that it will bring more improvements to DTS and Dolby audio which is more common on 360/PS3. This new cross-platform API is called XAudio2 and AFAIK is still in BETA.

One of the main improvements touted by Microsoft in DirectX 10.1 is improved access to shader resources - In particular, this involves better control when reading back samples from multi-sample anti-aliasing. In conjunction with this, the ability to create customised downsampling filters will be available in DirectX 10.1.

Floating point blending also gets some new functionality in DirectX 10.1, more specifically when used with render targets - New formats for render targets which support blending will be available in this iteration of the API, and render targets can now be blended independently of one another.

Shadows never fail to be an important part of any game title's graphics engine, and Direct3D 10.1 will see improvements to the shadow filtering capabilities within the API, which will hopefully lead to improvements in image quality in this regard.

On the performance side of things, DirectX 10.1 will allow for higher performance in multi-core systems, which is certainly good news for the ever growing numbers of dual-core users out there. The number of calls to the API when drawing and rendering reflections and refractions (two commonly used features in modern game titles) has been reduced in Direct3D 10.1, which should also make for some rather nice performance boosts. Finally, another oft-used feature, cube mapping, gets its own changes which should help with performance, in the form of the ability to use an indexable array for handling cube maps.

One of the major additions which will impact image quality in DirectX 10.1 regards precision, in a couple of different disciplines. 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. These increases in precision could make for an interesting challenge for the graphics IHVs, as it seems likely they'll be needing to spend a large number of transistors in future parts just to match these new requirements, let alone ekeing decent performance out of their GPUs when dealing with higher precisions than those we have seen thus far.

Again looking towards improvements on the image quality front, 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).

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