Method sample

src/testrender/shading.cpp:627–631

        return pdf = 0;
    }
    virtual float sample(const OSL::ShaderGlobals& sg, float rx, float ry, float rz, OSL::Dual2<OSL::Vec3>& wi, float& pdf) const {
        OSL::Dual2<OSL::Vec3> I = OSL::Dual2<OSL::Vec3>(sg.I, sg.dIdx, sg.dIdy);
        pdf = std::numeric_limits<float>::infinity();
        return fresnel_refraction(I, N, eta, wi);
    }
};

struct Transparent : public BSDF {