Direct2D fallback to GDI in XP

I'd like to use Direct2D for my .Net application using the Windows Code pack. Since some of my users are using XP, I need to provide a GDI+ fallback. I wonder how people usually do this kind of fallback.

Do they abstract/interface all the necessary graphics feature into some custom generic library? If so, is there any open-source开发者_如何学Python library for direct2d/GDI?

Thanks, Gil.

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The way I do it is by having two completely seperate classes (both derived from an IRenderer interface). On load, I determine the operating system version using Window's GetVersionEx function. If dwMajorVersion >= 6, then I load the Direct2D class; otherwise it falls back to GDI.

Hope this helps.

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You'll have to re-program it in Direct3D if you want it to run as fast.