These 2D/3D chairs are cleverly made by Japanese architect Yoichi Yamamoto. Specially for the Issey Miyake store in Tokyo. These chairs backs by Japanese architect Yoichi Yamamoto appear to have legs and seats when you viewed them from the outside of the store . Although the wooden backs of the blue chairs are fixed directly to the floor, the legs are painted onto the ground so that from a fixed angle they appear in the correct perspective. via here.