def generate_ray_differential(self, sample):
"""Generate a RayDifferential from the camera."""
# generate the ray
weight, ray = self.generate_ray(sample)
ray_diff = RayDifferential.from_ray(ray)
# find ray after shifting one pixel in the x direction
sshift = CameraSample.from_sample(sample)
sshift.image_x += 1
weight_x, ray_x = self.generate_ray(sshift)
ray_diff.rx_origin = ray_x.o
ray_diff.rx_direction = ray_x.d
# find ray after shifting one pixel in the y direction
sshift.image_x -= 1
sshift.image_y += 1
weight_y, ray_y = self.generate_ray(sshift)
ray_diff.ry_origin = ray_y.o
ray_diff.ry_direction = ray_y.d
if (weight_x == 0.0) or (weight_y == 0.0):
return 0.0, ray_diff
ray_diff.has_differentials = True
return weight, ray_diff
def generate_ray_differential(self, sample):
"""Generate a RayDifferential from the camera."""
# generate the ray
weight, ray = self.generate_ray(sample)
ray_diff = RayDifferential.from_ray(ray)
# find ray after shifting one pixel in the x direction
sshift = CameraSample.from_sample(sample)
sshift.image_x += 1
weight_x, ray_x = self.generate_ray(sshift)
ray_diff.rx_origin = ray_x.o
ray_diff.rx_direction = ray_x.d
# find ray after shifting one pixel in the y direction
sshift.image_x -= 1
sshift.image_y += 1
weight_y, ray_y = self.generate_ray(sshift)
ray_diff.ry_origin = ray_y.o
ray_diff.ry_direction = ray_y.d
if (weight_x == 0.0) or (weight_y == 0.0):
return 0.0, ray_diff
ray_diff.has_differentials = True
return weight, ray_diff
def test_ray_differential(self):
r = Ray(Point(0, 0, 0), Vector(1, 2, 3))
rd = RayDifferential(Point(0, 0, 0), Vector(1, 2, 3))
# test copy constructor from Ray
rd.has_differentials = True
rd1 = RayDifferential.from_ray_differential(rd)
self.assertTrue(isinstance(rd1, RayDifferential))
self.assertEqual(rd1.o, rd.o)
self.assertEqual(rd1.d, rd.d)
self.assertEqual(rd1.rx_origin, rd.rx_origin)
self.assertEqual(rd1.ry_origin, rd.ry_origin)
self.assertEqual(rd1.rx_direction, rd.rx_direction)
self.assertEqual(rd1.ry_direction, rd.ry_direction)
self.assertEqual(rd1.has_differentials, rd.has_differentials)
# test copy constructor from Ray
rd2 = RayDifferential.from_ray(r)
self.assertTrue(isinstance(rd2, RayDifferential))
self.assertEqual(rd2.d, r.d)
self.assertEqual(rd2.has_differentials, False)
# test constructor from parent ray
rd3 = RayDifferential.from_ray_parent(r.o, r.d, r, r.mint)
self.assertTrue(isinstance(rd3, RayDifferential))
self.assertEqual(rd3.depth, r.depth+1)
# test operator()
p = rd(1.7)
self.assertEqual(p, Point(1.7, 3.4, 5.1))
def test_ray_differential(self):
r = Ray(Point(0, 0, 0), Vector(1, 2, 3))
rd = RayDifferential(Point(0, 0, 0), Vector(1, 2, 3))
# test copy constructor from Ray
rd.has_differentials = True
rd1 = RayDifferential.from_ray_differential(rd)
self.assertTrue(isinstance(rd1, RayDifferential))
self.assertEqual(rd1.o, rd.o)
self.assertEqual(rd1.d, rd.d)
self.assertEqual(rd1.rx_origin, rd.rx_origin)
self.assertEqual(rd1.ry_origin, rd.ry_origin)
self.assertEqual(rd1.rx_direction, rd.rx_direction)
self.assertEqual(rd1.ry_direction, rd.ry_direction)
self.assertEqual(rd1.has_differentials, rd.has_differentials)
# test copy constructor from Ray
rd2 = RayDifferential.from_ray(r)
self.assertTrue(isinstance(rd2, RayDifferential))
self.assertEqual(rd2.d, r.d)
self.assertEqual(rd2.has_differentials, False)
# test constructor from parent ray
rd3 = RayDifferential.from_ray_parent(r.o, r.d, r, r.mint)
self.assertTrue(isinstance(rd3, RayDifferential))
self.assertEqual(rd3.depth, r.depth + 1)
# test operator()
p = rd(1.7)
self.assertEqual(p, Point(1.7, 3.4, 5.1))
