Best Swap Buffer Format, RGBA or BGRA ?

Question

In June 2010 SDK, the most format is  DXGI_FORMAT_R8G8B8A8_UNORM (_SRGB)

Why Metro Samples now use DXGI_FORMAT_B8G8R8A8_UNORM ,  For compatibility reason or performance reason ?

Answer 1

DXGI 1.0 / Direct3D 10 only supported RGB formats, not BGR.

DXGI 1.1 / Direct3D 11 added some BGR formats, but since these required WDDM 1.1 drivers to support we stuck with RGB formats for better 'compat' with Windows Vista.

Since all Metro style applications are Windows 8, you can count on DirectX 11.1 and WDDM 1.2 drivers or at least WDDM 1.1 drivers.

I believe there are some flip optimizatoin benefits to using BGR rather than RGB.

Answer 2

Yes , BGR is about 5% faster than RGB as I tested.

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C++ DX11