def test_TIR(self):
"""With rays exiting a glass, some are TIR'ed, some not"""
n1 = 1.5
n2 = 1.
dir = N.c_[[0, -1, 0], N.r_[0, -1, -1]/math.sqrt(2)]
norm = N.c_[[0, -1, 0]]
refr, dirs = optics.refractions(n1, n2, dir, norm)
N.testing.assert_array_equal(refr, N.r_[True, False])
N.testing.assert_array_equal(dirs, N.c_[[0,-1,0]])
def test_multiple_ref_idxs(self):
n1 = N.r_[1., 1.]
n2 = N.r_[1., 1.5]
dir = N.c_[[0, -1, 1], [0, -1, -1]]/math.sqrt(2)
norm = N.c_[[0, 1, 0]]
refr, dirs = optics.refractions(n1, n2, dir, norm)
self.failUnless(refr.all(), "Some rays did not refract")
correct_refrs = N.c_[dir[:,0], -N.sqrt([0, 7./9, 2./9])]
N.testing.assert_array_almost_equal(dirs, correct_refrs)
def test_reverse_normal(self):
"""When the normal points into the new material, refractions ok"""
n1 = N.r_[1., 1.]
n2 = N.r_[1., 1.5]
dir = N.c_[[0, -1, 1], [0, -1, -1]]/math.sqrt(2)
norm = N.c_[[0, -1, 0]]
refr, dirs = optics.refractions(n1, n2, dir, norm)
self.failUnless(refr.all(), "Some rays did not refract")
correct_refrs = N.c_[dir[:,0], -N.sqrt([0, 7./9, 2./9])]
N.testing.assert_array_almost_equal(dirs, correct_refrs)
def test_single_ref_idx(self):
"""Single refractive index is acceptable for refractions"""
n1 = 1.
n2 = 1.5
dir = N.c_[[0, -1, 1], [0, -1, -1]]/math.sqrt(2)
norm = N.c_[[0, -1, 0]]
refr, dirs = optics.refractions(n1, n2, dir, norm)
self.failUnless(refr.all(), "Some rays did not refract")
correct_refrs = N.c_[N.sqrt([0, 7./9, 2./9])*N.r_[0,-1,1], -N.sqrt([0, 7./9, 2./9])]
N.testing.assert_array_almost_equal(dirs, correct_refrs)
