PR summary

add_patch is currently very slow since it does bezier checks on all lines, but we can fast-path this for the common straight line case. In the below test script, add_patch dropped from 139 seconds to 50 milliseconds (~2700x improvement).

import numpy as np
import matplotlib.pyplot as plt
from matplotlib.path import Path
from matplotlib.patches import PathPatch

np.random.seed(0)
n = 100000
verts = np.random.rand(n, 2)
codes = np.full(n, Path.LINETO, dtype=np.uint8)
codes[0] = Path.MOVETO
p = Path(verts, codes)

fig, ax = plt.subplots()
for _ in range(10):
    ax.add_patch(PathPatch(p))
plt.close(fig)

AI Disclosure

Manually identified, claude suggested edits, manually reviewed / edited.

PR checklist

• [n/a] "closes #0000" is in the body of the PR description to link the related issue
• new and changed code is tested
• [n/a] Plotting related features are demonstrated in an example
• [n/a] New Features and API Changes are noted with a directive and release note
• Documentation complies with general and docstring guidelines