def test_normal(self):
surf = sf.sphere(1)
surf.swap()
u = np.linspace(surf.start(0) + 1e-3, surf.end(0) - 1e-3, 9)
v = np.linspace(surf.start(1) + 1e-3, surf.end(1) - 1e-3, 9)
xpts = surf(u, v, tensor=False)
npts = surf.normal(u, v, tensor=False)
self.assertEqual(npts.shape, (9, 3))
# check that the normal is pointing out of the unit ball on a 9x9 evaluation grid
for (x, n) in zip(xpts, npts):
self.assertAlmostEqual(n[0], x[0])
self.assertAlmostEqual(n[1], x[1])
self.assertAlmostEqual(n[2], x[2])
xpts = surf(u, v)
npts = surf.normal(u, v)
self.assertEqual(npts.shape, (9, 9, 3))
# check that the normal is pointing out of the unit ball on a 9x9 evaluation grid
for (i, j) in zip(xpts, npts):
for (x, n) in zip(i, j):
self.assertAlmostEqual(n[0], x[0])
self.assertAlmostEqual(n[1], x[1])
self.assertAlmostEqual(n[2], x[2])
# check single value input
n = surf.normal(0, 0)
self.assertEqual(len(n), 3)
# test 2D surface
s = Surface()
n = s.normal(.5, .5)
self.assertEqual(len(n), 3)
self.assertAlmostEqual(n[0], 0.0)
self.assertAlmostEqual(n[1], 0.0)
self.assertAlmostEqual(n[2], 1.0)
n = s.normal([.25, .5], [.1, .2, .3, .4, .5, .6, .7, .8, .9])
self.assertEqual(n.shape[0], 2)
self.assertEqual(n.shape[1], 9)
self.assertEqual(n.shape[2], 3)
self.assertAlmostEqual(n[1, 4, 0], 0.0)
self.assertAlmostEqual(n[1, 4, 1], 0.0)
self.assertAlmostEqual(n[1, 4, 2], 1.0)
n = s.normal([.25, .5, .75], [.3, .5, .9], tensor=False)
self.assertEqual(n.shape, (3, 3))
for i in range(3):
for j in range(2):
self.assertAlmostEqual(n[i, j], 0.0)
self.assertAlmostEqual(n[i, 2], 1.0)
# test errors
s = Surface(BSplineBasis(3), BSplineBasis(3), [[0]] * 9) # 1D-surface
with self.assertRaises(RuntimeError):
s.normal(.5, .5)
