declare shader
    color "cook_torrance" (
        color  "ambient"                  default 0 0 0,
        color  "diffuse"                  default 1 1 1,
	color  "specular"                 default 0 0 0,
	scalar "average_microfacet_slope" default .2,
	color  "index_of_refraction"      default 1 1 1,
        array light "lights"
    )
    version 1
    apply material
end declare