def test_the_color_when_a_ray_misses__only_negative_intersection_t():
w = World()
w.light = PointLight(Point(-10, 10, -10), Color(1, 1, 1))
w.objects = [Plane()]
r = Ray(Point(0, 10, 0), Vector(0, 1, 1).normalize())
c = w.color_at(r)
assert c == Color(0, 0, 0)
def test_a_point_light_has_a_position_and_intensity():
# Given
intensity = Color(1, 1, 1)
position = Point(0, 0, 0)
# When
light = PointLight(position, intensity)
# Then
assert light.position == position
assert light.intensity == intensity
def test_shading_an_intersection_from_the_inside():
# Given
w = default_world()
w.light = PointLight(Point(0, 0.25, 0), Color(1, 1, 1))
r = Ray(Point(0, 0, 0), Vector(0, 0, 1))
shape = w.objects[1]
i = Intersection(0.5, shape)
# When
comps = i.prepare_computations(r)
c = w.shade_hit(comps)
# Then
assert c == Color(0.90498, 0.90498, 0.90498)
def test_lighting_with_the_light_behind_the_surface():
# Given
m = Material()
position = Point(0, 0, 0)
eyev = Vector(0, 0, -1)
normalv = Vector(0, 0, -1)
light = PointLight(Point(0, 0, 10), Color(1, 1, 1))
object = Sphere()
# When
result = m.lighting(object, light, position, eyev, normalv)
# Then
assert result == Color(0.1, 0.1, 0.1)
def test_lighting_with_the_eye_in_the_path_of_the_reflection_vector():
# Given
m = Material()
position = Point(0, 0, 0)
eyev = Vector(0, -sqrt(2) / 2, -sqrt(2) / 2)
normalv = Vector(0, 0, -1)
light = PointLight(Point(0, 10, -10), Color(1, 1, 1))
object = Sphere()
# When
result = m.lighting(object, light, position, eyev, normalv)
# Then
assert result == Color(1.6364, 1.6364, 1.6364)
def test_lighting_with_the_eye_opposite_surface_light_offset_45degree():
# Given
m = Material()
position = Point(0, 0, 0)
eyev = Vector(0, 0, -1)
normalv = Vector(0, 0, -1)
light = PointLight(Point(0, 10, -10), Color(1, 1, 1))
object = Sphere()
# When
result = m.lighting(object, light, position, eyev, normalv)
# Then
assert result == Color(0.7364, 0.7364, 0.7364)
def test_lighting_with_the_eye_between_light_and_surface_eye_offset_45degree():
# Given
m = Material()
position = Point(0, 0, 0)
eyev = Vector(0, sqrt(2) / 2, sqrt(2) / 2)
normalv = Vector(0, 0, -1)
light = PointLight(Point(0, 0, -10), Color(1, 1, 1))
object = Sphere()
# When
result = m.lighting(object, light, position, eyev, normalv)
# Then
assert result == Color(1.0, 1.0, 1.0)
def default_world():
light = PointLight(Point(-10, 10, -10), Color(1, 1, 1))
s1 = Sphere()
s1.material.color = Color(0.8, 1.0, 0.6)
s1.material.diffuse = 0.7
s1.material.specular = 0.2
s2 = Sphere()
s2.transform = scaling(0.5, 0.5, 0.5)
w = World()
w.light = light
w.objects = [s1, s2]
return w
def test_default_world():
# Given
light = PointLight(Point(-10, 10, -10), Color(1, 1, 1))
s1 = Sphere()
s1.material.color = Color(0.8, 1.0, 0.6)
s1.material.diffuse = 0.7
s1.material.specular = 0.2
s2 = Sphere()
s2.transform = scaling(0.5, 0.5, 0.5)
# When
w = default_world()
# Then
assert w.light == light
assert s1 in w.objects
assert s2 in w.objects
def test__shade_hit__is_given_an_intersection_in_shadow():
# Given
w = World()
w.light = PointLight(Point(0, 0, -10), Color(1, 1, 1))
s1 = Sphere()
w.objects.append(s1)
s2 = Sphere()
s2.transform = translation(0, 0, 10)
w.objects.append(s2)
r = Ray(Point(0, 0, 5), Vector(0, 0, 1))
i = Intersection(4, s2)
# When
comps = i.prepare_computations(r)
c = w.shade_hit(comps)
# Then
assert c == Color(0.1, 0.1, 0.1)
def test_lighting_with_a_pattern_applied():
# Given
m = Material()
m.pattern = StripePattern(Color(1, 1, 1), Color(0, 0, 0))
m.ambient = 1
m.diffuse = 0
m.specular = 0
eyev = Vector(0, 0, -1)
normalv = Vector(0, 0, -1)
light = PointLight(Point(0, 0, -10), Color(1, 1, 1))
object = Sphere()
# When
c1 = m.lighting(object, light, Point(0.9, 0, 0), eyev, normalv)
c2 = m.lighting(object, light, Point(1.1, 0, 0), eyev, normalv)
# Then
assert c1 == Color(1, 1, 1)
assert c2 == Color(0, 0, 0)
def test__color_at__with_mutually_reflective_surfaces():
# Given
w = World()
w.light = PointLight(Point(0, 0, 0), Color(1, 1, 1))
lower = Plane()
lower.material.reflective = 1
lower.transform = translation(0, -1, 0)
w.objects.append(lower)
upper = Plane()
upper.material.reflective = 1
upper.transform = translation(0, 1, 0)
w.objects.append(upper)
r = Ray(Point(0, 0, 0), Vector(0, 1, 0))
# Then
try:
w.color_at(r)
except RecursionError:
pytest.fail("Unexpected RecursionError ...")
# right.material.pattern = pattern
# right.material.diffuse = 0.7
# right.material.specular = 0.3
right.material.diffuse = 0
right.material.specular = 0
left = Sphere()
left.transform = translation(-1.5, 0.33, -0.75) * scaling(0.33, 0.33, 0.33)
left.material = Material()
left.material.color = Color(1, 0.8, 0.1)
# left.material.pattern = pattern
left.material.diffuse = 0.7
left.material.specular = 0.3
cube = Cube()
cube.transform = translation(
0, 0, 1) * rotation_y(pi / 4) * scaling(0.5, 0.5, 0.5)
world = World()
# world.objects = [floor, backdrop, backdrop2, middle, right, left]
world.objects = [cube]
world.light = PointLight(Point(-10, 10, -10), Color(1, 1, 1))
camera = Camera(100, 50, pi / 3)
camera.transform = view_transform(Point(0, 1.5, -5),
Point(0, 1, 0),
Vector(0, 1, 0))
canvas = camera.render(world)
print(canvas.to_ppm())
if __name__ == "__main__":
ray_origin = Point(0, 0, -5)
wall_z = 10
wall_size = 7.0
canvas_pixcels = 100
pixel_size = wall_size / canvas_pixcels
half = wall_size / 2
canvas = Canvas(canvas_pixcels, canvas_pixcels)
shape = Sphere()
shape.material = Material()
shape.material.color = Color(1, 0.2, 1)
light_position = Point(-10, 10, -10)
light_color = Color(1, 1, 1)
light = PointLight(light_position, light_color)
# for each row of pixels in the canvas
for y in range(canvas_pixcels):
# compute the world y coordinate (top = +half, bottom = -half)
world_y = half - pixel_size * y
for x in range(canvas_pixcels):
# compute the world x coordinate (left = -half, right = half)
world_x = -half + pixel_size * x
# describe the point on the wall that the ray will target
position = Point(world_x, world_y, wall_z)
r = Ray(ray_origin, (position - ray_origin).normalize())
xs = shape.intersect(r)