What are the uses for SV_POSITION in the pixel shader? Previously this was the POSITION semantic and it wasn't readable in the pixel shader, but now that it is, what can it be used for?
In an SM2 deferred renderer, you'd typically take the texture coordinates, transform them to the [-1, 1] range and then use an inverse view/position matrix to get the world position of a pixel. Would SV_POSITION be usable here to reduce any of the calculations? And if so, how would you do that?