fr/fr_env/lib/python3.8/site-packages/matplotlib/tests/test_agg.py

247 lines
7.3 KiB
Python

import io
import numpy as np
from numpy.testing import assert_array_almost_equal
from PIL import Image, TiffTags
import pytest
from matplotlib import (
collections, path, pyplot as plt, transforms as mtransforms, rcParams)
from matplotlib.image import imread
from matplotlib.figure import Figure
from matplotlib.testing.decorators import image_comparison
def test_repeated_save_with_alpha():
# We want an image which has a background color of bluish green, with an
# alpha of 0.25.
fig = Figure([1, 0.4])
fig.set_facecolor((0, 1, 0.4))
fig.patch.set_alpha(0.25)
# The target color is fig.patch.get_facecolor()
buf = io.BytesIO()
fig.savefig(buf,
facecolor=fig.get_facecolor(),
edgecolor='none')
# Save the figure again to check that the
# colors don't bleed from the previous renderer.
buf.seek(0)
fig.savefig(buf,
facecolor=fig.get_facecolor(),
edgecolor='none')
# Check the first pixel has the desired color & alpha
# (approx: 0, 1.0, 0.4, 0.25)
buf.seek(0)
assert_array_almost_equal(tuple(imread(buf)[0, 0]),
(0.0, 1.0, 0.4, 0.250),
decimal=3)
def test_large_single_path_collection():
buff = io.BytesIO()
# Generates a too-large single path in a path collection that
# would cause a segfault if the draw_markers optimization is
# applied.
f, ax = plt.subplots()
collection = collections.PathCollection(
[path.Path([[-10, 5], [10, 5], [10, -5], [-10, -5], [-10, 5]])])
ax.add_artist(collection)
ax.set_xlim(10**-3, 1)
plt.savefig(buff)
def test_marker_with_nan():
# This creates a marker with nans in it, which was segfaulting the
# Agg backend (see #3722)
fig, ax = plt.subplots(1)
steps = 1000
data = np.arange(steps)
ax.semilogx(data)
ax.fill_between(data, data*0.8, data*1.2)
buf = io.BytesIO()
fig.savefig(buf, format='png')
def test_long_path():
buff = io.BytesIO()
fig, ax = plt.subplots()
np.random.seed(0)
points = np.random.rand(70000)
ax.plot(points)
fig.savefig(buff, format='png')
@image_comparison(['agg_filter.png'], remove_text=True)
def test_agg_filter():
def smooth1d(x, window_len):
# copied from http://www.scipy.org/Cookbook/SignalSmooth
s = np.r_[
2*x[0] - x[window_len:1:-1], x, 2*x[-1] - x[-1:-window_len:-1]]
w = np.hanning(window_len)
y = np.convolve(w/w.sum(), s, mode='same')
return y[window_len-1:-window_len+1]
def smooth2d(A, sigma=3):
window_len = max(int(sigma), 3) * 2 + 1
A = np.apply_along_axis(smooth1d, 0, A, window_len)
A = np.apply_along_axis(smooth1d, 1, A, window_len)
return A
class BaseFilter:
def get_pad(self, dpi):
return 0
def process_image(self, padded_src, dpi):
raise NotImplementedError("Should be overridden by subclasses")
def __call__(self, im, dpi):
pad = self.get_pad(dpi)
padded_src = np.pad(im, [(pad, pad), (pad, pad), (0, 0)],
"constant")
tgt_image = self.process_image(padded_src, dpi)
return tgt_image, -pad, -pad
class OffsetFilter(BaseFilter):
def __init__(self, offsets=(0, 0)):
self.offsets = offsets
def get_pad(self, dpi):
return int(max(self.offsets) / 72 * dpi)
def process_image(self, padded_src, dpi):
ox, oy = self.offsets
a1 = np.roll(padded_src, int(ox / 72 * dpi), axis=1)
a2 = np.roll(a1, -int(oy / 72 * dpi), axis=0)
return a2
class GaussianFilter(BaseFilter):
"""Simple Gaussian filter."""
def __init__(self, sigma, alpha=0.5, color=(0, 0, 0)):
self.sigma = sigma
self.alpha = alpha
self.color = color
def get_pad(self, dpi):
return int(self.sigma*3 / 72 * dpi)
def process_image(self, padded_src, dpi):
tgt_image = np.empty_like(padded_src)
tgt_image[:, :, :3] = self.color
tgt_image[:, :, 3] = smooth2d(padded_src[:, :, 3] * self.alpha,
self.sigma / 72 * dpi)
return tgt_image
class DropShadowFilter(BaseFilter):
def __init__(self, sigma, alpha=0.3, color=(0, 0, 0), offsets=(0, 0)):
self.gauss_filter = GaussianFilter(sigma, alpha, color)
self.offset_filter = OffsetFilter(offsets)
def get_pad(self, dpi):
return max(self.gauss_filter.get_pad(dpi),
self.offset_filter.get_pad(dpi))
def process_image(self, padded_src, dpi):
t1 = self.gauss_filter.process_image(padded_src, dpi)
t2 = self.offset_filter.process_image(t1, dpi)
return t2
fig, ax = plt.subplots()
# draw lines
l1, = ax.plot([0.1, 0.5, 0.9], [0.1, 0.9, 0.5], "bo-",
mec="b", mfc="w", lw=5, mew=3, ms=10, label="Line 1")
l2, = ax.plot([0.1, 0.5, 0.9], [0.5, 0.2, 0.7], "ro-",
mec="r", mfc="w", lw=5, mew=3, ms=10, label="Line 1")
gauss = DropShadowFilter(4)
for l in [l1, l2]:
# draw shadows with same lines with slight offset.
xx = l.get_xdata()
yy = l.get_ydata()
shadow, = ax.plot(xx, yy)
shadow.update_from(l)
# offset transform
ot = mtransforms.offset_copy(l.get_transform(), ax.figure,
x=4.0, y=-6.0, units='points')
shadow.set_transform(ot)
# adjust zorder of the shadow lines so that it is drawn below the
# original lines
shadow.set_zorder(l.get_zorder() - 0.5)
shadow.set_agg_filter(gauss)
shadow.set_rasterized(True) # to support mixed-mode renderers
ax.set_xlim(0., 1.)
ax.set_ylim(0., 1.)
ax.xaxis.set_visible(False)
ax.yaxis.set_visible(False)
def test_too_large_image():
fig = plt.figure(figsize=(300, 1000))
buff = io.BytesIO()
with pytest.raises(ValueError):
fig.savefig(buff)
def test_chunksize():
x = range(200)
# Test without chunksize
fig, ax = plt.subplots()
ax.plot(x, np.sin(x))
fig.canvas.draw()
# Test with chunksize
fig, ax = plt.subplots()
rcParams['agg.path.chunksize'] = 105
ax.plot(x, np.sin(x))
fig.canvas.draw()
@pytest.mark.backend('Agg')
def test_jpeg_dpi():
# Check that dpi is set correctly in jpg files.
plt.plot([0, 1, 2], [0, 1, 0])
buf = io.BytesIO()
plt.savefig(buf, format="jpg", dpi=200)
im = Image.open(buf)
assert im.info['dpi'] == (200, 200)
def test_pil_kwargs_png():
from PIL.PngImagePlugin import PngInfo
buf = io.BytesIO()
pnginfo = PngInfo()
pnginfo.add_text("Software", "test")
plt.figure().savefig(buf, format="png", pil_kwargs={"pnginfo": pnginfo})
im = Image.open(buf)
assert im.info["Software"] == "test"
def test_pil_kwargs_tiff():
buf = io.BytesIO()
pil_kwargs = {"description": "test image"}
plt.figure().savefig(buf, format="tiff", pil_kwargs=pil_kwargs)
im = Image.open(buf)
tags = {TiffTags.TAGS_V2[k].name: v for k, v in im.tag_v2.items()}
assert tags["ImageDescription"] == "test image"