def test_imshow_clip():
# As originally reported by Gellule Xg <*****@*****.**>
#Create a NxN image
N = 100
(x, y) = np.indices((N, N))
x -= N / 2
y -= N / 2
r = np.sqrt(x**2 + y**2 - x * y)
#Create a contour plot at N/4 and extract both the clip path and transform
fig = plt.figure()
ax = fig.add_subplot(111)
c = ax.contour(r, [N / 4])
x = c.collections[0]
clipPath = x.get_paths()[0]
clipTransform = x.get_transform()
from matplotlib.transforms import TransformedPath
clip_path = TransformedPath(clipPath, clipTransform)
#Plot the image clipped by the contour
ax.imshow(r, clip_path=clip_path)
fig.savefig('imshow_clip')
def _get_display_coordination(artist):
"""
Ref: matplotlib.lines.Line2D.contains
It is intended to transform the coordination system
to ``display``.
Is it really necessary?
"""
transformed_path = TransformedPath(artist.get_path(),
artist.get_transform())
path, affine = transformed_path.get_transformed_path_and_affine()
path = affine.transform_path(path)
xy = path.vertices
return xy
def test_transformed_path():
points = [(0, 0), (1, 0), (1, 1), (0, 1)]
codes = [Path.MOVETO, Path.LINETO, Path.LINETO, Path.CLOSEPOLY]
path = Path(points, codes)
trans = mtrans.Affine2D()
trans_path = TransformedPath(path, trans)
assert np.allclose(trans_path.get_fully_transformed_path().vertices,
points)
# Changing the transform should change the result.
r2 = 1 / np.sqrt(2)
trans.rotate(np.pi / 4)
assert np.allclose(trans_path.get_fully_transformed_path().vertices,
[(0, 0), (r2, r2), (0, 2 * r2), (-r2, r2)])
# Changing the path does not change the result (it's cached).
path.points = [(0, 0)] * 4
assert np.allclose(trans_path.get_fully_transformed_path().vertices,
[(0, 0), (r2, r2), (0, 2 * r2), (-r2, r2)])
def recache(self):
self._transformed_path = TransformedPath(self._path,
self.get_transform())
self._invalid = False
def _get_transformed_clip_path(self):
x, y, width, height = self.state.clipping_path
rect = ((x, y), (x + width, y), (x + width, y + height), (x,
y + height))
transform = Affine2D.from_values(*affine.affine_params(self.get_ctm()))
return TransformedPath(Path(rect), transform)
def _transform_path(self):
_path = Path(self._xydata)
self._transformed_path = TransformedPath(_path, self.get_transform())
