def test_computing_normal_on_scaled_sphere(self): s = Sphere() s.set_transform(scaling(1, 0.5, 1)) n = s.normal_at(point(0, math.sqrt(2) / 2, -math.sqrt(2) / 2)) self.assert_tuple_equals(vector(0, 0.97014, -0.24254), n, 0.001)
def test_computing_normal_on_translated_sphere(self): s = Sphere() s.set_transform(translation(0, 1, 0)) n = s.normal_at(point(0, 1.70711, -0.70711)) self.assert_tuple_equals(vector(0, 0.70711, -0.70711), n, 0.001)
def test_normal_is_normalized_vector(self): s = Sphere() n = s.normal_at( point(math.sqrt(3) / 3, math.sqrt(3) / 3, math.sqrt(3) / 3)) self.assertEqual(n.normalize(), n)
def test_normal_on_sphere_at_point_on_none_axial_point(self): s = Sphere() n = s.normal_at( point(math.sqrt(3) / 3, math.sqrt(3) / 3, math.sqrt(3) / 3)) self.assertEqual(n.normalize(), n)
wall_size = 7.0 canvas_pixels = 1000 pixel_size = wall_size / canvas_pixels half = wall_size / 2 c = Canvas(canvas_pixels, canvas_pixels) col = color(1, 0, 0) start_time = time.time() for y in range(canvas_pixels): elapsed_time = time.time() - start_time if elapsed_time > 0 and y > 0: print("time_to_finish: " + str(1.0 * (canvas_pixels - y) / (1.0 * y / elapsed_time))) world_y = half - pixel_size * y for x in range(canvas_pixels): world_x = -half + pixel_size * x position = point(world_x, world_y, wall_z) ray = Ray(ray_origin, (position - ray_origin).normalize()) xs = s.intersect(ray) if hit(xs): hit_point = ray.position(hit(xs).t) norma_at_hit_point = s.normal_at(hit_point) eye = -ray.direction color = s.material.lighting(light, hit_point, eye, norma_at_hit_point) c.write_pixel(x, y, color) c.save_to_file('sphere6.ppm')
def test_normal_on_sphere_at_point_on_y_axis(self): s = Sphere() n = s.normal_at(point(0, 1, 0)) self.assertEqual(vector(0, 1, 0), n)