Patent attributes
A circuit for calculating a light reflected component with high accuracy. The circuit for calculating a reflected component of light reflected from an object having a rough surface comprises a means for storing the reflectance of an object in relation to the value φ or the value of cos φ, letting a surface normal vector be denoted by a vector N, a light source incidence unit vector be denoted by a vector L, a line-of-sight unit vector be denoted by V, a half vector of the light source incidence vector L and the line-of-sight vector V be denoted by H and defining the inner products as N·L=cos θ, N·V=cos γ, V·H=cos φ, N·H=cos β; a means for storing a luminance distribution in relation to the value of β or the value of cos β; a means for acquiring information on the reflectance term (Fλ(φ)) of the reflected component according to the value of φ or the value of cos φ from the reflectance storing means; a means for acquiring information on the luminance distribution term (D′(β)) of the reflected component according to the value of β or the value of cos β from the luminance distribution storing means; a means for acquiring information on max[0.5 cos θ cos φ, 0.5 cos φ cos γ, cos θ cos β cos γ] which is the maximum value out of 0.5 cos θ cos φ, 0.5 cos φ cos γ, cos θ cos β cos γ; a means for determining the reciprocal of the max[0.5 cos θ cos φ, 0.5 cos φ cos γ, cos θ cos β cos γ] and acquiring information on the geometrical attenuation factor term G′(β, θ, γ, φ) of the reflected component; and a means for acquiring information on the reflected component from the information on the luminance distribution term (D′(β)) and information on the geometrical attenuation factor term G′(β, θ, γ, φ).
