ONE OF OUR WISE WHISPERERS has suggested that the next implementation of DirectX 9 won't be labelled 9.1 at all. As many readers will be aware, the most recent revision of DX is 9.0b. And the upcoming implementation is likely simply to be called DirectX 9.0c, our greybeard suggests. The next revision of the famous API will be no DirectX 9.1. And, in terms of new features, it won't be a huge step that we saw with transition from DX 8.0 to 8.1.
DX 8.1 introduced new shader models and upgraded them from PS 1.3 to 1.4 -- a huge boost for ATI at that time since they could render some shaders in less passes with PS 1.4 than Nvidia's 1.1 or 1.3 shader models. We've been talking about PS 3.0 and its availability in DX 9 for at least six months. Indeed six months ago we were told that the next revision will be called 9.1 The name, of course, is not as important as the features. 9.0c will be matched with the Software Developers Kit 2004 update and it will have bug fixes that will improve Shaders 3.0.
We also expect it to enable 3.0's higher lever shading language (HLSL) support in D3D - finally. Shader 3.0 support is there already, we're just awaiting hardware that will support it. In this light, yesterday's information that NV40 won't support DX 9.1 is completely true. And the R420 will work with 9.0c only, as there will be no DX 9.1 - yet - even though 9.1 sounds prettier to our ears. We don't have precise timings as to when it will be released but It should be out really soon. It may match the late March announcements of NV40 and R420
News source: The Inq