Note
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Mmh Donuts!!!#
Draw donuts (miam!) using Paths and PathPatches.
This example shows the effect of the path's orientations in a compound path.
import matplotlib.pyplot as plt
import numpy as np
import matplotlib.patches as mpatches
import matplotlib.path as mpath
def wise(v):
return {+1: "CCW", -1: "CW"}[v]
def make_circle(r):
t = np.arange(0, np.pi * 2.0, 0.01)
x = r * np.cos(t)
y = r * np.sin(t)
return np.column_stack((x, y))
fig, ax = plt.subplots()
inside_vertices = make_circle(0.5)
outside_vertices = make_circle(1.0)
codes = np.full(len(inside_vertices), mpath.Path.LINETO)
codes[0] = mpath.Path.MOVETO
for i, (inside, outside) in enumerate(((1, 1), (1, -1), (-1, 1), (-1, -1))):
# Concatenate the inside and outside subpaths together, changing their
# order as needed
vertices = np.concatenate((outside_vertices[::outside],
inside_vertices[::inside]))
# Shift the path
vertices += (i * 2.5, 0)
# The codes will be all "LINETO" commands, except for "MOVETO"s at the
# beginning of each subpath
all_codes = np.concatenate((codes, codes))
# Create the Path object
path = mpath.Path(vertices, all_codes)
# And plot it
patch = mpatches.PathPatch(path, facecolor='#885500', edgecolor='black')
ax.add_patch(patch)
ax.annotate(f"Outside {wise(outside)},\nInside {wise(inside)}",
(i * 2.5, -1.5), va="top", ha="center")
ax.set(xlim=(-2, 10), ylim=(-3, 2), aspect=1, title="Mmm, donuts!")
plt.show()
References
The use of the following functions, methods, classes and modules is shown in this example: