1. A method of representing a virtual object in a view of a real environment, comprising: obtaining a first image of at least part of a human face in a real environment captured by a first camera; determining one or more image positions in the first image corresponding to one or more face sample positions, wherein the one or more face sample positions are each associated with a known radiance transfer function; determining at least one first light according to intensity information associated with the one or more image positions and the radiance transfer functions associated with the one or more face sample positions corresponding to the image positions in the first image; and displaying the virtual object on a display device in the view of the real environment according to the at least one first light.