1. A structure for representing an image having a plurality of pixels, the structure comprising: a plurality of tile elements held in a fixed relationship to one another, each of the tile elements comprising a generally planar surface inclined at an inclination angle with respect to a reference plane, each of the tile elements corresponding to at least one pixel of the image and having an orientation angle with respect to a reference direction, the orientation angle defined between projections, on the reference plane, of: a line normal to the generally planar surface; and a line parallel to the reference direction, wherein the orientation angle is determined by a characteristic of the corresponding at least one pixel.