Path.intersects_path returns True when it shouldn't #15842
Description
Bug report
Bug summary
Path.intersects_path returns True for the following paths, when they don't intersect at all (as shown by Shapely). This is a simplified outline_path from Cartopy. The trigger seems to be the duplicate point at the end of outline_path; if removed, it works as expected.
A bisect says this broke in bd3fd8f, which is a backport of #11553 to 3.1.0. cc @TarasKuzyo
Code for reproduction
import numpy as np
import matplotlib as mpl
from matplotlib.path import Path
from shapely.geometry import LinearRing
this_path = Path(
np.array([
[824.85064295, 2056.26489203],
[861.69033931, 2041.00539016],
[868.57864109, 2057.63522175],
[831.73894473, 2072.89472361],
[824.85064295, 2056.26489203]]),
np.array([1, 2, 2, 2, 79], dtype=Path.code_type))
this_ring = LinearRing(this_path.vertices)
outline_path = Path(
np.array([
[859.91051028, 2165.38461538],
[859.06772495, 2149.30331334],
[859.06772495, 2181.46591743],
[859.91051028, 2165.38461538],
[859.91051028, 2165.38461538]]),
np.array([1, 2, 2, 2, 2],
dtype=Path.code_type))
outline_ring = LinearRing(outline_path.vertices)
print(mpl.__version__, outline_path.intersects_path(this_path),
outline_ring.intersects(this_ring))Actual outcome
3.1.2 True False
Expected outcome
3.1.2 False False
Matplotlib version
- Operating system: Fedora 30
- Matplotlib version: 3.1.2
- Matplotlib backend (
print(matplotlib.get_backend())): N/A - Python version: 3.7
- Jupyter version (if applicable): N/A
- Other libraries: N/A