def test_alpha_blend_normal_rgb_with_opaque_source():
cb = util.fill((2, 2), [0, 128, 255])
cs = util.fill((2, 2), [255, 128, 0, 1])
cr = alpha_blend(cb, cs, _normal)
expected = split_alpha(cs)[0]
assert cr == expected
def test_alpha_blend_normal_opaque_backdrop_with_transparent_source():
cb = util.fill((2, 2), [0, 128, 255, 1])
cs = util.fill((2, 2), [255, 128, 0, 0])
cr = alpha_blend(cb, cs, _normal)
expected = split_alpha(cb)[0]
assert cr == expected
def test_alpha_blend_call_blending(mocker):
cb = util.fill((2, 2), [0, 128, 255, 1])
cs = util.fill((2, 2), [255, 128, 0, 1])
return_value, _ = split_alpha(cs)
normal_stub = mocker.Mock(return_value=return_value)
alpha_blend(cb, cs, normal_stub)
# TODO: assert with parameters
normal_stub.assert_called_once()
def test_normal2():
cb = util.fill((2, 2), [255, 128, 0, 1.])
cs_array = np.array([
[[0, 128, 255, .25], [0, 255, 128, .5]],
[[128, 255, 0, .75], [128, 0, 255, .1]],
],
dtype=np.uint8)
cs = Image.fromarray(cs_array)
actual = css.blending.normal(cb, cs)
expected, _ = split_alpha(Image.alpha_composite(cb, cs))
assert actual == expected
def test_split_alpha_unsupported_mode():
im = Image.new('L', (2, 2), 128)
with pytest.raises(ValueError):
split_alpha(im)
def test_split_alpha_rgb():
im = util.fill((2, 2), [0, 128, 255])
rgb, a = split_alpha(im)
assert id(rgb) == id(im)
assert a is None
def test_split_alpha_rgba():
im = util.fill((2, 2), [0, 128, 255, .5])
rgb, a = split_alpha(im)
assert rgb == util.fill((2, 2), [0, 128, 255])
assert a == Image.new('L', (2, 2), 128)