The way of modeling of speculardiffuse character of light reflection from real surfaces is proposed in the paper. Model of structurally complex reflecting boundary baseson the open billiards. Indicatrix of reflection from this surface for all angles of incidence consists only of specular pike and diffuse component. Dependence of the share of specular component on an angle of incidence may be any predefined function, its choice also defines the shape of diffuse component.
