Right after reports went live focusing on a Microsoft Answers Q&A about DirectX 11.1 being a Windows 8 exclusive, Chuck Walbourn from Microsoft said on the Games for Windows blog that portions of the DirectX 11.1 runtime will be made available for Windows 7 after all.
According to Walbourn, Windows 8 includes an updated 'DirectX 11.1 Runtime' that supports Direct3D 11.1, updates Direct2D and DirectWrite, DXGI 1.2, and a revision of the Windows Imaging Component (WIC).
"Portions of the 'DirectX 11.1 Runtime' are being made available on Windows 7 Service Pack 1 via the Platform Update for Windows 7 Service Pack 1 and Windows Server 2008 R2 Service Pack 1 (KB 2670838) included with the Internet Explorer 10 Release Preview for Windows 7," he writes. "This includes the updated components above, but is limited to WDDM 1.1 drivers on Windows 7."
According to the update notes, the patch improves the features and performance of Direct2D, DirectWrite, Direct3D, Windows Imaging Component (WIC), Windows Advanced Rasterization Platform (WARP), Windows Animation Manager (WAM), XPS Document API, H.264 Video Decoder and the JPEG XR codec.
Walbourn's blog adds more detail to the update:
* ID3D11Device1, ID2D1Factory1, IDWriteFactory1, IDXGIFactory2, IWICImagingFactory2, ID3DUserDefinedAnnotation and related APIs are available. Methods that depend on WDDM 1.2 drivers or new Windows Store app APIs are not supported.
* Improved Direct3D 11 device interoperability via ID3DDeviceContextState, including the improved interop with Direct2D/DirectWrite
* D3D11_FEATURE_DATA_D3D9_OPTIONS feature detection
* In addition to the new Windows 8 WIC features, this update also fixes decoding of 96bpp floating-point TIFF images.