def test_bounded_cylinder_bounding_box(self):
shape = Cylinder()
shape.minimum = -5
shape.maximum = 3
box = shape.bounds_of()
self.assertEqual(box.min, Point(-1, -5, -1))
self.assertEqual(box.max, Point(1, 3, 1))
def test_group_bounding_box_contains_children(self):
s = Sphere()
s.transform = Transformations.translation(2, 5, -3).dot(
Transformations.scaling(2, 2, 2))
c = Cylinder()
c.minimum = -2
c.maximum = 2
c.transform = Transformations.translation(-4, -1, 4).dot(
Transformations.scaling(0.5, 1, 0.5))
shape = Group()
shape.add_child(s)
shape.add_child(c)
box = shape.bounds_of()
self.assertEqual(box.min, Point(-4.5, -3, -5))
self.assertEqual(box.max, Point(4, 7, 4.5))
def test_normal_vector_cylinder_end_caps(self):
cyl = Cylinder()
cyl.minimum = 1
cyl.maximum = 2
cyl.closed = True
PointNormal = namedtuple("PointNormal", ["point", "normal"])
point_normals = [
PointNormal(Point(0, 1, 0), Vector(0, -1, 0)),
PointNormal(Point(0.5, 1, 0), Vector(0, -1, 0)),
PointNormal(Point(0, 1, 0.5), Vector(0, -1, 0)),
PointNormal(Point(0, 2, 0), Vector(0, 1, 0)),
PointNormal(Point(0.5, 2, 0), Vector(0, 1, 0)),
PointNormal(Point(0, 2, 0.5), Vector(0, 1, 0))
]
for point_normal in point_normals:
n = cyl.local_normal_at(point_normal.point)
self.assertEqual(n, point_normal.normal)
def test_intersect_constrained_cylinder(self):
cyl = Cylinder()
cyl.minimum = 1
cyl.maximum = 2
CylinderIntersection = namedtuple("CyliderIntersection",
["point", "direction", "count"])
cylinder_intersections = [
CylinderIntersection(Point(0, 1.5, 0), Vector(0.1, 1, 0), 0),
CylinderIntersection(Point(0, 3, -5), Vector(0, 0, 1), 0),
CylinderIntersection(Point(0, 0, -5), Vector(0, 0, 1), 0),
CylinderIntersection(Point(0, 2, -5), Vector(0, 0, 1), 0),
CylinderIntersection(Point(0, 1, -5), Vector(0, 0, 1), 0),
CylinderIntersection(Point(0, 1.5, -2), Vector(0, 0, 1), 2)
]
for cylinder_intersection in cylinder_intersections:
direction = Vector.normalize(cylinder_intersection.direction)
r = Ray(cylinder_intersection.point, direction)
xs = cyl.local_intersect(r)
self.assertEqual(len(xs), cylinder_intersection.count)
def test_interserct_caps_of_closed_cylinder(self):
cyl = Cylinder()
cyl.minimum = 1
cyl.maximum = 2
cyl.closed = True
cyl.maximum = 2
CylinderIntersection = namedtuple("CyliderIntersection",
["point", "direction", "count"])
cylinder_intersections = [
CylinderIntersection(Point(0, 3, 0), Vector(0, -1, 0), 2),
CylinderIntersection(Point(0, 3, -2), Vector(0, -1, 2), 2),
CylinderIntersection(Point(0, 4, -2), Vector(0, -1, 1),
2), # corner case
CylinderIntersection(Point(0, 0, -2), Vector(0, 1, 2), 2),
CylinderIntersection(Point(0, -1, -2), Vector(0, 1, 1),
2) # corner case
]
for cylinder_intersection in cylinder_intersections:
direction = Vector.normalize(cylinder_intersection.direction)
r = Ray(cylinder_intersection.point, direction)
xs = cyl.local_intersect(r)
self.assertEqual(len(xs), cylinder_intersection.count)