vec4 castRay(vec4 p0, vec4 E, Object *lastHitObject, int depth){

    std::vector<Object:: IntersectionValues> results (sceneObjects.size());
    Object::IntersectionValues min_intersect = sceneObjects[0]->intersect(p0,E);
    vec4 color = vec4 (0., 0., 0., 0.) ;
    min_intersect.t_w = std::numeric_limits< double >::infinity();

    if(depth > maxDepth){
        return color;
    }

    for(unsigned int i=0; i < sceneObjects.size(); i++) {
         Object::IntersectionValues intersect =sceneObjects[i]->intersect(p0,E);
         results[i] = sceneObjects[i] -> intersect(p0, E);
         min_intersect.ID_ = i;
         results[i].ID_ = i;
        if (min_intersect.t_w > intersect.t_w) {
            min_intersect = intersect;
        }
    }

    std::sort(results.begin(),results.end(),intersectionSort);
    if(min_intersect.t_w != std::numeric_limits<double>::infinity() ){

            int id = results[0].ID_;
            float material_shininess= sceneObjects[id]->shadingValues.Kn;
            color4 material_ambient(sceneObjects[id]->shadingValues.color.x*sceneObjects[id]->shadingValues.Ka,
                                    sceneObjects[id]->shadingValues.color.y*sceneObjects[id]->shadingValues.Ka,
                                    sceneObjects[id]->shadingValues.color.z*sceneObjects[id]->shadingValues.Ka, 1.0 );

            color4 material_diffuse(sceneObjects[id]->shadingValues.color.x,
                                    sceneObjects[id]->shadingValues.color.y,
                                    sceneObjects[id]->shadingValues.color.z, 1.0 );

            color4 material_specular(sceneObjects[id]->shadingValues.Ks,
                                     sceneObjects[id]->shadingValues.Ks,
                                     sceneObjects[id]->shadingValues.Ks, 1.0 );


            color4 ambient_product  = GLState::light_ambient * material_ambient;
            ambient_product.w = 1.0;
            color4 diffuse_product  = GLState::light_diffuse * material_diffuse;
            diffuse_product.w = 1.0;
            color4 specular_product = GLState::light_specular * material_specular;
            specular_product.w = 1.0;

            vec4 L = normalize(lightPosition - min_intersect.P_w);
            L.w = 0.0;

        vec4 N= normalize(min_intersect.N_w);
        vec4 R= normalize(reflect(L, min_intersect.N_w));
        vec4 V= normalize(E);
        float Kd = fmax( dot(L, N), 0.0 );
        float Ks = pow( fmax(dot(R,V), 0.0), material_shininess );

        if (sceneObjects[id] -> shadingValues.Ks>0){
            vec4 reflectance = normalize(E - 2 * dot(E, N) * N);
            vec4 specular =  Ks * specular_product * castRay(p0, reflectance, sceneObjects[id], depth+1);;

        }


        vec4 ambient= ambient_product;
        vec4 diffuse= Kd * diffuse_product;
        vec4 specular =  Ks * specular_product;
        color= ambient+diffuse+specular;
        if(shadowFeeler(min_intersect.P_w, sceneObjects[id]) != 0){
            color = vec4(0.0,0.0,0.0,1.0);
        }
    }

    if(color.x > 1.0){ color.x = 1.0; }
    if(color.y > 1.0){ color.y = 1.0; }
    if(color.z > 1.0){ color.z = 1.0; }

    color.w =1.0;
    return color;

}