Chapter 11 - Fresnel Effect - Test #1

Hello! fails test №1

my world(scene):

    w.s[0] = set_sphere(0);

    w.max_obj = 1;

    w.ar_count = 0;

    push_obj((void*)(&w.s[0]), &normal_at_sp, &intersect_sp, &shade_hit_sp, &w, &w.s[0].m);

    glass_sp(w.s[0]);


    r = set_ray(set_v_p(0, 0, sqrt(2)/2, 1), set_v_p(0, 1, 0, 0));


    xs.max_obj = 2;

    xs.i[0].t = -sqrt(2)/2;

    xs.i[0].obj = 0;
    

    xs.i[1].t = sqrt(2)/2;

    xs.i[1].obj = 0;



t_comps comps = prepare_computations(xs.i[1], r, w, xs);

double reflectance = schlick(comps);


my answer:

n1 = 1.000000

n2 = 1.000000

reflectance = 0.000000

comps.t 0.707107


double schlick(t_comps c)

{

double cos;

double n;

double sin2_t;

double cos_t;

double r0;



cos = dot(c.eyev, c.normalv);

printf("n1 schlick = %f\n", c.n1);

printf("n2 schlick = %f\n", c.n2);

if (c.n1 > c.n2)

{

n = c.n1 / c.n2;

sin2_t = (n * n) * (1.0 - (cos * cos));

printf("sin2_t = %f\n", sin2_t);

if (sin2_t > 1.0)

{

return (1.0);

}

}

return (0.0);

}

t_comps prepare_computations(t_i i, t_ray r, t_world w, t_xs xs)

{

t_comps c;

t_vec normal;



c.t = i.t;

c.obj = i.obj;

c.point = position(r, c.t);

c.eyev = neg(r.d);

if ((*w.obj_ar[c.obj].loc_norm)(w.obj_ar[c.obj].obj, c.point, &normal) == 0)

printf("normal error");

else

c.normalv = normal;


if (dot(c.normalv, c.eyev) < 0)

{

c.inside = 1;

c.normalv = neg(c.normalv);

}

else

{

c.inside = 0;

}

c.over_point = add(c.point, mult(c.normalv, EPSILON));

c.reflectv = reflect(r.d, c.normalv);

c.under_point = sub(c.point, mult(c.normalv, EPSILON));



c = comps_n_calculate(w, i, xs, c);




return(c);

}


t_comps comps_n_calculate(t_world w, t_i i, t_xs xs, t_comps c)

{

t_arr containers;

containers.size = 0;

int aa = 0;

while (aa < xs.max_obj)

{

t_i curr_i = xs.i[aa];

if (curr_i.t == i.t && curr_i.obj == i.obj)

{

if (containers.size == 0)

{

c.n1 = 1.0;

}

else

{

c.n1 = w.obj_ar[containers.arr[containers.size - 1]].m->refractive_index;

}

}

int flag = -1;

int bb = 0;

while (bb < containers.size)

{

if (containers.arr[bb] == curr_i.obj)

{

flag = bb;

}

bb++;

}

if (flag > -1)

{

containers.arr[flag] = -1;

containers = removenull(containers);

}

else

{

containers.arr[containers.size] = curr_i.obj;

containers.size = containers.size + 1;

}

if (curr_i.t == i.t && curr_i.obj == i.obj)

{

if (containers.size == 0)

{

c.n2 = 1.0;

}

else

{

c.n2 = w.obj_ar[containers.arr[containers.size - 1]].m->refractive_index;

}

aa = xs.max_obj;

}

aa++;

}

return (c);

}