what's the mean in ID3D11DeviceContext::OMSetBlendState [SampleMask]

[Baesky]

I had read the msdn http://msdn.microsoft.com/en-us/library/windows/desktop/ff476462(v=vs.85).aspx
I still do not understand the mean of SampleMask.
Does the MultiSampleMask determin which texture sampler to use?
Or releative to MSAA?

thanks in advance!

 

[satanir]

samplemask

SampleMask determines which samples are updated in the render-target. It's a bit-mask, each bit corresponds to a pixel's sample.
For example, in MSAAx4, you can set the sample mask to 0x1, then only the first sample will be updated.
GPUs will usually cull the pixel in the rasterizer stage, so no shading/depth test for masked samples.

I really have no idea why this isn't a part of the rasterizer state...