Coming to DirectX 12— Sampler Feedback: some useful once-hidden data, unlocked
Suppose you are shading a complicated 3D scene. The camera moves swiftly throughout the scene, causing some objects to be moved into different levels of detail. Since you need to aggressively optimize for memory, you bind resources to cope with the demand for different LODs. Perhaps you use a texture streaming system; perhaps it uses tiled resources to keep those gigantic 4K mip 0s non-resident if you don’t need them. Anyway, you have a shader which samples a mipped texture using A Very Complicated sampling pattern. Pick your favorite one, say anisotropic.