uh... you don't really give us a lot to go on. What exactly are you trying to do? What is the problem you're experiencing?
From what I can tell, it looks like you're trying to create a screen shot texture of the current window and are rendering it as a quad. You say something about blurring, though it looks like you're doing it manually?
One option is to take a screenshot of the current buffer, apply it to a texture, and then scale the texture down. This has the downside in that it consumes a lot more video memory, but does the blurring on the graphics card.
The other option is to dynamically create a smaller texture. The process is similar to the method above, but you'd want to apply "super sampling" to your original scene based on the resolution of your target texture size. You pretty much map a pixel from your target texture to your original scene. If the target resolution is smaller than the original scene, you should have overlap of more than one pixel from the original scene. You take the collection of these overlapped pixels and average all of the RGB values into a final pixel color result. This is done manually on the CPU, so it can be a bit more expensive.
Hi, sorry, I will make sense about it.
I try to scale the texture down, but the result of the texture were looked weird. I used a smaller texture ( screenwidth / 2, screenheight / 2 ) for scaling down. but finally ,I got 1 of 4 , a part of original texture (I mean I got only left-top part of the original texture, not the whole scene). I don't know how to fix it in DirectX 11, because the scaling down procedure was totally handled by DirectX.