Thermal energy has been proposed to have ever greater potential for human beings if the heat carriers, i.e. phonons can be controlled in micron scale as easy as its counterpart, electrons in solid. Alternatively, in macroscopical scale, functional thermal materials are used to control thermal energy. The transformation of macroscopical thermal diffusion equation is proposed to obtain the asymmetrical thermal conductivity in real space. This new type of thermal functional materials helps to control heat flow and to realize thermal cloak and thermal camouflage.