Well, it looks like those early adopters might be left somewhat in the lurch, as Microsoft has recently announced that Windows Vista SP1 will include a minor version upgrade to DirectX – DirectX 10.1. This includes some features originally intended for DirectX 10 but which had to be left to one side, and as such DirectX 10.1 is a superset of DirectX 10 – supporting all of DirectX 10’s features with some additions and enhancements of its own.
DirectX 10.1 offers greater application control of the GPU’s shading and filtering resources, especially multi-sampled and super-sampled antialiasing. The shader model is updated from 4.0 to 4.1, and floating point technology is beefed up from 16-bit to full 32-bit, which should demonstrate a direct improvement in quality for HDR (High Dynamic Range) lighting effects. In addition, all DirectX 10.1-capable hardware should be able to run 4xAA (antialiasing) as a mandatory setting.
So all this is great news, right? If you lashed out on a DirectX 10 card, then perhaps not. Although DirectX 10.1 is fully backwards-compatible with DirectX 10 features and hardware, the reverse isn’t true. Neither NVIDIA’s GeForce 8 series nor ATI’s Radeon HD 2x series of GPUs support DirectX 10.1. ATI’s new products – the Radeon 3870 and 3850 – do support DirectX 10.1, but NVIDIA apparently has no plans to release a DirectX 10.1-capable GPU. Their next product range, codenamed GT200, will support DirectX 11, but as this is due for release before DirectX 11 itself it will be interesting to see how well early products based on this GPU will support the new DirectX technology.