Version 3.0.3
"""
Abstract base classes define the primitives that renderers and
graphics contexts must implement to serve as a matplotlib backend
:class:`RendererBase`
An abstract base class to handle drawing/rendering operations.
:class:`FigureCanvasBase`
The abstraction layer that separates the
:class:`matplotlib.figure.Figure` from the backend specific
details like a user interface drawing area
:class:`GraphicsContextBase`
An abstract base class that provides color, line styles, etc...
:class:`Event`
The base class for all of the matplotlib event
handling. Derived classes such as :class:`KeyEvent` and
:class:`MouseEvent` store the meta data like keys and buttons
pressed, x and y locations in pixel and
:class:`~matplotlib.axes.Axes` coordinates.
:class:`ShowBase`
The base class for the Show class of each interactive backend;
the 'show' callable is then set to Show.__call__, inherited from
ShowBase.
:class:`ToolContainerBase`
The base class for the Toolbar class of each interactive backend.
:class:`StatusbarBase`
The base class for the messaging area.
"""
from contextlib import contextmanager
import importlib
import io
import os
import sys
import time
import warnings
from weakref import WeakKeyDictionary
import numpy as np
from matplotlib import (
backend_tools as tools, cbook, colors, textpath, tight_bbox, transforms,
widgets, get_backend, is_interactive, rcParams)
from matplotlib._pylab_helpers import Gcf
from matplotlib.transforms import Bbox, TransformedBbox, Affine2D
from matplotlib.path import Path
try:
from PIL import Image
from PIL import PILLOW_VERSION
from distutils.version import LooseVersion
if LooseVersion(PILLOW_VERSION) >= "3.4":
_has_pil = True
else:
_has_pil = False
del Image
except ImportError:
_has_pil = False
_default_filetypes = {
'ps': 'Postscript',
'eps': 'Encapsulated Postscript',
'pdf': 'Portable Document Format',
'pgf': 'PGF code for LaTeX',
'png': 'Portable Network Graphics',
'raw': 'Raw RGBA bitmap',
'rgba': 'Raw RGBA bitmap',
'svg': 'Scalable Vector Graphics',
'svgz': 'Scalable Vector Graphics'
}
_default_backends = {
'ps': 'matplotlib.backends.backend_ps',
'eps': 'matplotlib.backends.backend_ps',
'pdf': 'matplotlib.backends.backend_pdf',
'pgf': 'matplotlib.backends.backend_pgf',
'png': 'matplotlib.backends.backend_agg',
'raw': 'matplotlib.backends.backend_agg',
'rgba': 'matplotlib.backends.backend_agg',
'svg': 'matplotlib.backends.backend_svg',
'svgz': 'matplotlib.backends.backend_svg',
}
[docs]def register_backend(format, backend, description=None):
"""
Register a backend for saving to a given file format.
Parameters
----------
format : str
File extension
backend : module string or canvas class
Backend for handling file output
description : str, optional
Description of the file type. Defaults to an empty string
"""
if description is None:
description = ''
_default_backends[format] = backend
_default_filetypes[format] = description
[docs]def get_registered_canvas_class(format):
"""
Return the registered default canvas for given file format.
Handles deferred import of required backend.
"""
if format not in _default_backends:
return None
backend_class = _default_backends[format]
if isinstance(backend_class, str):
backend_class = importlib.import_module(backend_class).FigureCanvas
_default_backends[format] = backend_class
return backend_class
[docs]class RendererBase(object):
"""An abstract base class to handle drawing/rendering operations.
The following methods must be implemented in the backend for full
functionality (though just implementing :meth:`draw_path` alone would
give a highly capable backend):
* :meth:`draw_path`
* :meth:`draw_image`
* :meth:`draw_gouraud_triangle`
The following methods *should* be implemented in the backend for
optimization reasons:
* :meth:`draw_text`
* :meth:`draw_markers`
* :meth:`draw_path_collection`
* :meth:`draw_quad_mesh`
"""
def __init__(self):
self._texmanager = None
self._text2path = textpath.TextToPath()
[docs] def open_group(self, s, gid=None):
"""
Open a grouping element with label *s*. If *gid* is given, use
*gid* as the id of the group. Is only currently used by
:mod:`~matplotlib.backends.backend_svg`.
"""
[docs] def close_group(self, s):
"""
Close a grouping element with label *s*
Is only currently used by :mod:`~matplotlib.backends.backend_svg`
"""
[docs] def draw_path(self, gc, path, transform, rgbFace=None):
"""
Draws a :class:`~matplotlib.path.Path` instance using the
given affine transform.
"""
raise NotImplementedError
[docs] def draw_markers(self, gc, marker_path, marker_trans, path,
trans, rgbFace=None):
"""
Draws a marker at each of the vertices in path. This includes
all vertices, including control points on curves. To avoid
that behavior, those vertices should be removed before calling
this function.
This provides a fallback implementation of draw_markers that
makes multiple calls to :meth:`draw_path`. Some backends may
want to override this method in order to draw the marker only
once and reuse it multiple times.
Parameters
----------
gc : `GraphicsContextBase`
The graphics context
marker_trans : `matplotlib.transforms.Transform`
An affine transform applied to the marker.
trans : `matplotlib.transforms.Transform`
An affine transform applied to the path.
"""
for vertices, codes in path.iter_segments(trans, simplify=False):
if len(vertices):
x, y = vertices[-2:]
self.draw_path(gc, marker_path,
marker_trans +
transforms.Affine2D().translate(x, y),
rgbFace)
[docs] def draw_path_collection(self, gc, master_transform, paths, all_transforms,
offsets, offsetTrans, facecolors, edgecolors,
linewidths, linestyles, antialiaseds, urls,
offset_position):
"""
Draws a collection of paths selecting drawing properties from
the lists *facecolors*, *edgecolors*, *linewidths*,
*linestyles* and *antialiaseds*. *offsets* is a list of
offsets to apply to each of the paths. The offsets in
*offsets* are first transformed by *offsetTrans* before being
applied. *offset_position* may be either "screen" or "data"
depending on the space that the offsets are in.
This provides a fallback implementation of
:meth:`draw_path_collection` that makes multiple calls to
:meth:`draw_path`. Some backends may want to override this in
order to render each set of path data only once, and then
reference that path multiple times with the different offsets,
colors, styles etc. The generator methods
:meth:`_iter_collection_raw_paths` and
:meth:`_iter_collection` are provided to help with (and
standardize) the implementation across backends. It is highly
recommended to use those generators, so that changes to the
behavior of :meth:`draw_path_collection` can be made globally.
"""
path_ids = []
for path, transform in self._iter_collection_raw_paths(
master_transform, paths, all_transforms):
path_ids.append((path, transforms.Affine2D(transform)))
for xo, yo, path_id, gc0, rgbFace in self._iter_collection(
gc, master_transform, all_transforms, path_ids, offsets,
offsetTrans, facecolors, edgecolors, linewidths, linestyles,
antialiaseds, urls, offset_position):
path, transform = path_id
transform = transforms.Affine2D(
transform.get_matrix()).translate(xo, yo)
self.draw_path(gc0, path, transform, rgbFace)
[docs] def draw_quad_mesh(self, gc, master_transform, meshWidth, meshHeight,
coordinates, offsets, offsetTrans, facecolors,
antialiased, edgecolors):
"""
This provides a fallback implementation of
:meth:`draw_quad_mesh` that generates paths and then calls
:meth:`draw_path_collection`.
"""
from matplotlib.collections import QuadMesh
paths = QuadMesh.convert_mesh_to_paths(
meshWidth, meshHeight, coordinates)
if edgecolors is None:
edgecolors = facecolors
linewidths = np.array([gc.get_linewidth()], float)
return self.draw_path_collection(
gc, master_transform, paths, [], offsets, offsetTrans, facecolors,
edgecolors, linewidths, [], [antialiased], [None], 'screen')
[docs] def draw_gouraud_triangle(self, gc, points, colors, transform):
"""
Draw a Gouraud-shaded triangle.
Parameters
----------
points : array_like, shape=(3, 2)
Array of (x, y) points for the triangle.
colors : array_like, shape=(3, 4)
RGBA colors for each point of the triangle.
transform : `matplotlib.transforms.Transform`
An affine transform to apply to the points.
"""
raise NotImplementedError
[docs] def draw_gouraud_triangles(self, gc, triangles_array, colors_array,
transform):
"""
Draws a series of Gouraud triangles.
Parameters
----------
points : array_like, shape=(N, 3, 2)
Array of *N* (x, y) points for the triangles.
colors : array_like, shape=(N, 3, 4)
Array of *N* RGBA colors for each point of the triangles.
transform : `matplotlib.transforms.Transform`
An affine transform to apply to the points.
"""
transform = transform.frozen()
for tri, col in zip(triangles_array, colors_array):
self.draw_gouraud_triangle(gc, tri, col, transform)
def _iter_collection_raw_paths(self, master_transform, paths,
all_transforms):
"""
This is a helper method (along with :meth:`_iter_collection`) to make
it easier to write a space-efficient :meth:`draw_path_collection`
implementation in a backend.
This method yields all of the base path/transform
combinations, given a master transform, a list of paths and
list of transforms.
The arguments should be exactly what is passed in to
:meth:`draw_path_collection`.
The backend should take each yielded path and transform and
create an object that can be referenced (reused) later.
"""
Npaths = len(paths)
Ntransforms = len(all_transforms)
N = max(Npaths, Ntransforms)
if Npaths == 0:
return
transform = transforms.IdentityTransform()
for i in range(N):
path = paths[i % Npaths]
if Ntransforms:
transform = Affine2D(all_transforms[i % Ntransforms])
yield path, transform + master_transform
def _iter_collection_uses_per_path(self, paths, all_transforms,
offsets, facecolors, edgecolors):
"""
Compute how many times each raw path object returned by
_iter_collection_raw_paths would be used when calling
_iter_collection. This is intended for the backend to decide
on the tradeoff between using the paths in-line and storing
them once and reusing. Rounds up in case the number of uses
is not the same for every path.
"""
Npaths = len(paths)
if Npaths == 0 or len(facecolors) == len(edgecolors) == 0:
return 0
Npath_ids = max(Npaths, len(all_transforms))
N = max(Npath_ids, len(offsets))
return (N + Npath_ids - 1) // Npath_ids
def _iter_collection(self, gc, master_transform, all_transforms,
path_ids, offsets, offsetTrans, facecolors,
edgecolors, linewidths, linestyles,
antialiaseds, urls, offset_position):
"""
This is a helper method (along with
:meth:`_iter_collection_raw_paths`) to make it easier to write
a space-efficient :meth:`draw_path_collection` implementation in a
backend.
This method yields all of the path, offset and graphics
context combinations to draw the path collection. The caller
should already have looped over the results of
:meth:`_iter_collection_raw_paths` to draw this collection.
The arguments should be the same as that passed into
:meth:`draw_path_collection`, with the exception of
*path_ids*, which is a list of arbitrary objects that the
backend will use to reference one of the paths created in the
:meth:`_iter_collection_raw_paths` stage.
Each yielded result is of the form::
xo, yo, path_id, gc, rgbFace
where *xo*, *yo* is an offset; *path_id* is one of the elements of
*path_ids*; *gc* is a graphics context and *rgbFace* is a color to
use for filling the path.
"""
Ntransforms = len(all_transforms)
Npaths = len(path_ids)
Noffsets = len(offsets)
N = max(Npaths, Noffsets)
Nfacecolors = len(facecolors)
Nedgecolors = len(edgecolors)
Nlinewidths = len(linewidths)
Nlinestyles = len(linestyles)
Naa = len(antialiaseds)
Nurls = len(urls)
if (Nfacecolors == 0 and Nedgecolors == 0) or Npaths == 0:
return
if Noffsets:
toffsets = offsetTrans.transform(offsets)
gc0 = self.new_gc()
gc0.copy_properties(gc)
if Nfacecolors == 0:
rgbFace = None
if Nedgecolors == 0:
gc0.set_linewidth(0.0)
xo, yo = 0, 0
for i in range(N):
path_id = path_ids[i % Npaths]
if Noffsets:
xo, yo = toffsets[i % Noffsets]
if offset_position == 'data':
if Ntransforms:
transform = (
Affine2D(all_transforms[i % Ntransforms]) +
master_transform)
else:
transform = master_transform
xo, yo = transform.transform_point((xo, yo))
xp, yp = transform.transform_point((0, 0))
xo = -(xp - xo)
yo = -(yp - yo)
if not (np.isfinite(xo) and np.isfinite(yo)):
continue
if Nfacecolors:
rgbFace = facecolors[i % Nfacecolors]
if Nedgecolors:
if Nlinewidths:
gc0.set_linewidth(linewidths[i % Nlinewidths])
if Nlinestyles:
gc0.set_dashes(*linestyles[i % Nlinestyles])
fg = edgecolors[i % Nedgecolors]
if len(fg) == 4:
if fg[3] == 0.0:
gc0.set_linewidth(0)
else:
gc0.set_foreground(fg)
else:
gc0.set_foreground(fg)
if rgbFace is not None and len(rgbFace) == 4:
if rgbFace[3] == 0:
rgbFace = None
gc0.set_antialiased(antialiaseds[i % Naa])
if Nurls:
gc0.set_url(urls[i % Nurls])
yield xo, yo, path_id, gc0, rgbFace
gc0.restore()
[docs] def get_image_magnification(self):
"""
Get the factor by which to magnify images passed to :meth:`draw_image`.
Allows a backend to have images at a different resolution to other
artists.
"""
return 1.0
[docs] def draw_image(self, gc, x, y, im, transform=None):
"""
Draw an RGBA image.
Parameters
----------
gc : `GraphicsContextBase`
a graphics context with clipping information.
x : scalar
the distance in physical units (i.e., dots or pixels) from the left
hand side of the canvas.
y : scalar
the distance in physical units (i.e., dots or pixels) from the
bottom side of the canvas.
im : array_like, shape=(N, M, 4), dtype=np.uint8
An array of RGBA pixels.
transform : `matplotlib.transforms.Affine2DBase`
If and only if the concrete backend is written such that
:meth:`option_scale_image` returns ``True``, an affine
transformation *may* be passed to :meth:`draw_image`. It takes the
form of a :class:`~matplotlib.transforms.Affine2DBase` instance.
The translation vector of the transformation is given in physical
units (i.e., dots or pixels). Note that the transformation does not
override `x` and `y`, and has to be applied *before* translating
the result by `x` and `y` (this can be accomplished by adding `x`
and `y` to the translation vector defined by `transform`).
"""
raise NotImplementedError
[docs] def option_image_nocomposite(self):
"""
override this method for renderers that do not necessarily always
want to rescale and composite raster images. (like SVG, PDF, or PS)
"""
return False
[docs] def option_scale_image(self):
"""
override this method for renderers that support arbitrary affine
transformations in :meth:`draw_image` (most vector backends).
"""
return False
[docs] def draw_tex(self, gc, x, y, s, prop, angle, ismath='TeX!', mtext=None):
"""
"""
self._draw_text_as_path(gc, x, y, s, prop, angle, ismath="TeX")
[docs] def draw_text(self, gc, x, y, s, prop, angle, ismath=False, mtext=None):
"""
Draw the text instance
Parameters
----------
gc : `GraphicsContextBase`
the graphics context
x : scalar
the x location of the text in display coords
y : scalar
the y location of the text baseline in display coords
s : str
the text string
prop : `matplotlib.font_manager.FontProperties`
font properties
angle : scalar
the rotation angle in degrees
mtext : `matplotlib.text.Text`
the original text object to be rendered
Notes
-----
**backend implementers note**
When you are trying to determine if you have gotten your bounding box
right (which is what enables the text layout/alignment to work
properly), it helps to change the line in text.py::
if 0: bbox_artist(self, renderer)
to if 1, and then the actual bounding box will be plotted along with
your text.
"""
self._draw_text_as_path(gc, x, y, s, prop, angle, ismath)
def _get_text_path_transform(self, x, y, s, prop, angle, ismath):
"""
return the text path and transform
Parameters
----------
prop : `matplotlib.font_manager.FontProperties`
font property
s : str
text to be converted
usetex : bool
If True, use matplotlib usetex mode.
ismath : bool
If True, use mathtext parser. If "TeX", use *usetex* mode.
"""
text2path = self._text2path
fontsize = self.points_to_pixels(prop.get_size_in_points())
if ismath == "TeX":
verts, codes = text2path.get_text_path(prop, s, ismath=False,
usetex=True)
else:
verts, codes = text2path.get_text_path(prop, s, ismath=ismath,
usetex=False)
path = Path(verts, codes)
angle = np.deg2rad(angle)
if self.flipy():
transform = Affine2D().scale(fontsize / text2path.FONT_SCALE,
fontsize / text2path.FONT_SCALE)
transform = transform.rotate(angle).translate(x, self.height - y)
else:
transform = Affine2D().scale(fontsize / text2path.FONT_SCALE,
fontsize / text2path.FONT_SCALE)
transform = transform.rotate(angle).translate(x, y)
return path, transform
def _draw_text_as_path(self, gc, x, y, s, prop, angle, ismath):
"""
draw the text by converting them to paths using textpath module.
Parameters
----------
prop : `matplotlib.font_manager.FontProperties`
font property
s : str
text to be converted
usetex : bool
If True, use matplotlib usetex mode.
ismath : bool
If True, use mathtext parser. If "TeX", use *usetex* mode.
"""
path, transform = self._get_text_path_transform(
x, y, s, prop, angle, ismath)
color = gc.get_rgb()
gc.set_linewidth(0.0)
self.draw_path(gc, path, transform, rgbFace=color)
[docs] def get_text_width_height_descent(self, s, prop, ismath):
"""
Get the width, height, and descent (offset from the bottom
to the baseline), in display coords, of the string *s* with
:class:`~matplotlib.font_manager.FontProperties` *prop*
"""
if ismath == 'TeX':
# todo: handle props
size = prop.get_size_in_points()
texmanager = self._text2path.get_texmanager()
fontsize = prop.get_size_in_points()
w, h, d = texmanager.get_text_width_height_descent(
s, fontsize, renderer=self)
return w, h, d
dpi = self.points_to_pixels(72)
if ismath:
dims = self._text2path.mathtext_parser.parse(s, dpi, prop)
return dims[0:3] # return width, height, descent
flags = self._text2path._get_hinting_flag()
font = self._text2path._get_font(prop)
size = prop.get_size_in_points()
font.set_size(size, dpi)
# the width and height of unrotated string
font.set_text(s, 0.0, flags=flags)
w, h = font.get_width_height()
d = font.get_descent()
w /= 64.0 # convert from subpixels
h /= 64.0
d /= 64.0
return w, h, d
[docs] def flipy(self):
"""
Return true if y small numbers are top for renderer Is used
for drawing text (:mod:`matplotlib.text`) and images
(:mod:`matplotlib.image`) only
"""
return True
[docs] def get_canvas_width_height(self):
'return the canvas width and height in display coords'
return 1, 1
[docs] def get_texmanager(self):
"""
return the :class:`matplotlib.texmanager.TexManager` instance
"""
if self._texmanager is None:
from matplotlib.texmanager import TexManager
self._texmanager = TexManager()
return self._texmanager
[docs] def new_gc(self):
"""
Return an instance of a :class:`GraphicsContextBase`
"""
return GraphicsContextBase()
[docs] def points_to_pixels(self, points):
"""
Convert points to display units
You need to override this function (unless your backend
doesn't have a dpi, e.g., postscript or svg). Some imaging
systems assume some value for pixels per inch::
points to pixels = points * pixels_per_inch/72.0 * dpi/72.0
Parameters
----------
points : scalar or array_like
a float or a numpy array of float
Returns
-------
Points converted to pixels
"""
return points
[docs] def start_rasterizing(self):
"""
Used in MixedModeRenderer. Switch to the raster renderer.
"""
[docs] def stop_rasterizing(self):
"""
Used in MixedModeRenderer. Switch back to the vector renderer
and draw the contents of the raster renderer as an image on
the vector renderer.
"""
[docs] def start_filter(self):
"""
Used in AggRenderer. Switch to a temporary renderer for image
filtering effects.
"""
[docs] def stop_filter(self, filter_func):
"""
Used in AggRenderer. Switch back to the original renderer.
The contents of the temporary renderer is processed with the
*filter_func* and is drawn on the original renderer as an
image.
"""
[docs]class GraphicsContextBase(object):
"""
An abstract base class that provides color, line styles, etc...
"""
def __init__(self):
self._alpha = 1.0
self._forced_alpha = False # if True, _alpha overrides A from RGBA
self._antialiased = 1 # use 0,1 not True, False for extension code
self._capstyle = 'butt'
self._cliprect = None
self._clippath = None
self._dashes = None, None
self._joinstyle = 'round'
self._linestyle = 'solid'
self._linewidth = 1
self._rgb = (0.0, 0.0, 0.0, 1.0)
self._hatch = None
self._hatch_color = colors.to_rgba(rcParams['hatch.color'])
self._hatch_linewidth = rcParams['hatch.linewidth']
self._url = None
self._gid = None
self._snap = None
self._sketch = None
[docs] def copy_properties(self, gc):
'Copy properties from gc to self'
self._alpha = gc._alpha
self._forced_alpha = gc._forced_alpha
self._antialiased = gc._antialiased
self._capstyle = gc._capstyle
self._cliprect = gc._cliprect
self._clippath = gc._clippath
self._dashes = gc._dashes
self._joinstyle = gc._joinstyle
self._linestyle = gc._linestyle
self._linewidth = gc._linewidth
self._rgb = gc._rgb
self._hatch = gc._hatch
self._hatch_color = gc._hatch_color
self._hatch_linewidth = gc._hatch_linewidth
self._url = gc._url
self._gid = gc._gid
self._snap = gc._snap
self._sketch = gc._sketch
[docs] def restore(self):
"""
Restore the graphics context from the stack - needed only
for backends that save graphics contexts on a stack
"""
[docs] def get_alpha(self):
"""
Return the alpha value used for blending - not supported on
all backends
"""
return self._alpha
[docs] def get_antialiased(self):
"Return true if the object should try to do antialiased rendering"
return self._antialiased
[docs] def get_capstyle(self):
"""
Return the capstyle as a string in ('butt', 'round', 'projecting')
"""
return self._capstyle
[docs] def get_clip_rectangle(self):
"""
Return the clip rectangle as a :class:`~matplotlib.transforms.Bbox`
instance
"""
return self._cliprect
[docs] def get_clip_path(self):
"""
Return the clip path in the form (path, transform), where path
is a :class:`~matplotlib.path.Path` instance, and transform is
an affine transform to apply to the path before clipping.
"""
if self._clippath is not None:
return self._clippath.get_transformed_path_and_affine()
return None, None
[docs] def get_dashes(self):
"""
Return the dash information as an offset dashlist tuple.
The dash list is a even size list that gives the ink on, ink
off in pixels.
See p107 of to PostScript `BLUEBOOK
<https://www-cdf.fnal.gov/offline/PostScript/BLUEBOOK.PDF>`_
for more info.
Default value is None
"""
return self._dashes
[docs] def get_forced_alpha(self):
"""
Return whether the value given by get_alpha() should be used to
override any other alpha-channel values.
"""
return self._forced_alpha
[docs] def get_joinstyle(self):
"""
Return the line join style as one of ('miter', 'round', 'bevel')
"""
return self._joinstyle
[docs] def get_linewidth(self):
"""
Return the line width in points as a scalar
"""
return self._linewidth
[docs] def get_rgb(self):
"""
returns a tuple of three or four floats from 0-1.
"""
return self._rgb
[docs] def get_gid(self):
"""
Return the object identifier if one is set, None otherwise.
"""
return self._gid
[docs] def get_snap(self):
"""
returns the snap setting which may be:
* True: snap vertices to the nearest pixel center
* False: leave vertices as-is
* None: (auto) If the path contains only rectilinear line
segments, round to the nearest pixel center
"""
return self._snap
[docs] def set_alpha(self, alpha):
"""
Set the alpha value used for blending - not supported on all backends.
If ``alpha=None`` (the default), the alpha components of the
foreground and fill colors will be used to set their respective
transparencies (where applicable); otherwise, ``alpha`` will override
them.
"""
if alpha is not None:
self._alpha = alpha
self._forced_alpha = True
else:
self._alpha = 1.0
self._forced_alpha = False
self.set_foreground(self._rgb, isRGBA=True)
[docs] def set_antialiased(self, b):
"""
True if object should be drawn with antialiased rendering
"""
# use 0, 1 to make life easier on extension code trying to read the gc
if b:
self._antialiased = 1
else:
self._antialiased = 0
[docs] def set_capstyle(self, cs):
"""
Set the capstyle as a string in ('butt', 'round', 'projecting')
"""
if cs in ('butt', 'round', 'projecting'):
self._capstyle = cs
else:
raise ValueError('Unrecognized cap style. Found %s' % cs)
[docs] def set_clip_rectangle(self, rectangle):
"""
Set the clip rectangle with sequence (left, bottom, width, height)
"""
self._cliprect = rectangle
[docs] def set_clip_path(self, path):
"""
Set the clip path and transformation. Path should be a
:class:`~matplotlib.transforms.TransformedPath` instance.
"""
if (path is not None
and not isinstance(path, transforms.TransformedPath)):
raise ValueError("Path should be a "
"matplotlib.transforms.TransformedPath instance")
self._clippath = path
[docs] def set_dashes(self, dash_offset, dash_list):
"""
Set the dash style for the gc.
Parameters
----------
dash_offset : float
is the offset (usually 0).
dash_list : array_like
specifies the on-off sequence as points.
``(None, None)`` specifies a solid line
"""
if dash_list is not None:
dl = np.asarray(dash_list)
if np.any(dl < 0.0):
raise ValueError(
"All values in the dash list must be positive")
self._dashes = dash_offset, dash_list
[docs] def set_foreground(self, fg, isRGBA=False):
"""
Set the foreground color. fg can be a MATLAB format string, a
html hex color string, an rgb or rgba unit tuple, or a float between 0
and 1. In the latter case, grayscale is used.
If you know fg is rgba, set ``isRGBA=True`` for efficiency.
"""
if self._forced_alpha and isRGBA:
self._rgb = fg[:3] + (self._alpha,)
elif self._forced_alpha:
self._rgb = colors.to_rgba(fg, self._alpha)
elif isRGBA:
self._rgb = fg
else:
self._rgb = colors.to_rgba(fg)
[docs] def set_joinstyle(self, js):
"""
Set the join style to be one of ('miter', 'round', 'bevel')
"""
if js in ('miter', 'round', 'bevel'):
self._joinstyle = js
else:
raise ValueError('Unrecognized join style. Found %s' % js)
[docs] def set_url(self, url):
"""
Sets the url for links in compatible backends
"""
self._url = url
[docs] def set_snap(self, snap):
"""
Sets the snap setting which may be:
* True: snap vertices to the nearest pixel center
* False: leave vertices as-is
* None: (auto) If the path contains only rectilinear line
segments, round to the nearest pixel center
"""
self._snap = snap
[docs] def get_hatch_path(self, density=6.0):
"""
Returns a Path for the current hatch.
"""
hatch = self.get_hatch()
if hatch is None:
return None
return Path.hatch(hatch, density)
[docs] def get_hatch_color(self):
"""
Gets the color to use for hatching.
"""
return self._hatch_color
[docs] def set_hatch_color(self, hatch_color):
"""
sets the color to use for hatching.
"""
self._hatch_color = hatch_color
[docs] def get_hatch_linewidth(self):
"""
Gets the linewidth to use for hatching.
"""
return self._hatch_linewidth
[docs] def get_sketch_params(self):
"""
Returns the sketch parameters for the artist.
Returns
-------
sketch_params : tuple or `None`
A 3-tuple with the following elements:
* `scale`: The amplitude of the wiggle perpendicular to the
source line.
* `length`: The length of the wiggle along the line.
* `randomness`: The scale factor by which the length is
shrunken or expanded.
May return `None` if no sketch parameters were set.
"""
return self._sketch
[docs] def set_sketch_params(self, scale=None, length=None, randomness=None):
"""
Sets the sketch parameters.
Parameters
----------
scale : float, optional
The amplitude of the wiggle perpendicular to the source
line, in pixels. If scale is `None`, or not provided, no
sketch filter will be provided.
length : float, optional
The length of the wiggle along the line, in pixels
(default 128)
randomness : float, optional
The scale factor by which the length is shrunken or
expanded (default 16)
"""
self._sketch = (
None if scale is None
else (scale, length or 128., randomness or 16.))
[docs]class TimerBase(object):
'''
A base class for providing timer events, useful for things animations.
Backends need to implement a few specific methods in order to use their
own timing mechanisms so that the timer events are integrated into their
event loops.
Mandatory functions that must be implemented:
* `_timer_start`: Contains backend-specific code for starting
the timer
* `_timer_stop`: Contains backend-specific code for stopping
the timer
Optional overrides:
* `_timer_set_single_shot`: Code for setting the timer to
single shot operating mode, if supported by the timer
object. If not, the `Timer` class itself will store the flag
and the `_on_timer` method should be overridden to support
such behavior.
* `_timer_set_interval`: Code for setting the interval on the
timer, if there is a method for doing so on the timer
object.
* `_on_timer`: This is the internal function that any timer
object should call, which will handle the task of running
all callbacks that have been set.
Attributes
----------
interval : scalar
The time between timer events in milliseconds. Default is 1000 ms.
single_shot : bool
Boolean flag indicating whether this timer should operate as single
shot (run once and then stop). Defaults to `False`.
callbacks : List[Tuple[callable, Tuple, Dict]]
Stores list of (func, args, kwargs) tuples that will be called upon
timer events. This list can be manipulated directly, or the
functions `add_callback` and `remove_callback` can be used.
'''
def __init__(self, interval=None, callbacks=None):
#Initialize empty callbacks list and setup default settings if necssary
if callbacks is None:
self.callbacks = []
else:
self.callbacks = callbacks[:] # Create a copy
if interval is None:
self._interval = 1000
else:
self._interval = interval
self._single = False
# Default attribute for holding the GUI-specific timer object
self._timer = None
def __del__(self):
'Need to stop timer and possibly disconnect timer.'
self._timer_stop()
[docs] def start(self, interval=None):
'''
Start the timer object. `interval` is optional and will be used
to reset the timer interval first if provided.
'''
if interval is not None:
self._set_interval(interval)
self._timer_start()
def _timer_start(self):
pass
def _timer_stop(self):
pass
def _get_interval(self):
return self._interval
def _set_interval(self, interval):
# Force to int since none of the backends actually support fractional
# milliseconds, and some error or give warnings.
interval = int(interval)
self._interval = interval
self._timer_set_interval()
interval = property(_get_interval, _set_interval)
def _get_single_shot(self):
return self._single
def _set_single_shot(self, ss=True):
self._single = ss
self._timer_set_single_shot()
single_shot = property(_get_single_shot, _set_single_shot)
[docs] def add_callback(self, func, *args, **kwargs):
'''
Register `func` to be called by timer when the event fires. Any
additional arguments provided will be passed to `func`.
'''
self.callbacks.append((func, args, kwargs))
[docs] def remove_callback(self, func, *args, **kwargs):
'''
Remove `func` from list of callbacks. `args` and `kwargs` are optional
and used to distinguish between copies of the same function registered
to be called with different arguments.
'''
if args or kwargs:
self.callbacks.remove((func, args, kwargs))
else:
funcs = [c[0] for c in self.callbacks]
if func in funcs:
self.callbacks.pop(funcs.index(func))
def _timer_set_interval(self):
"""Used to set interval on underlying timer object."""
def _timer_set_single_shot(self):
"""Used to set single shot on underlying timer object."""
def _on_timer(self):
'''
Runs all function that have been registered as callbacks. Functions
can return False (or 0) if they should not be called any more. If there
are no callbacks, the timer is automatically stopped.
'''
for func, args, kwargs in self.callbacks:
ret = func(*args, **kwargs)
# docstring above explains why we use `if ret == 0` here,
# instead of `if not ret`.
# This will also catch `ret == False` as `False == 0`
# but does not annoy the linters
# https://docs.python.org/3/library/stdtypes.html#boolean-values
if ret == 0:
self.callbacks.remove((func, args, kwargs))
if len(self.callbacks) == 0:
self.stop()
[docs]class Event(object):
"""
A matplotlib event. Attach additional attributes as defined in
:meth:`FigureCanvasBase.mpl_connect`. The following attributes
are defined and shown with their default values
Attributes
----------
name : str
the event name
canvas : `FigureCanvasBase`
the backend-specific canvas instance generating the event
guiEvent
the GUI event that triggered the matplotlib event
"""
def __init__(self, name, canvas, guiEvent=None):
self.name = name
self.canvas = canvas
self.guiEvent = guiEvent
[docs]class DrawEvent(Event):
"""
An event triggered by a draw operation on the canvas
In most backends callbacks subscribed to this callback will be
fired after the rendering is complete but before the screen is
updated. Any extra artists drawn to the canvas's renderer will
be reflected without an explicit call to ``blit``.
.. warning ::
Calling ``canvas.draw`` and ``canvas.blit`` in these callbacks may
not be safe with all backends and may cause infinite recursion.
In addition to the :class:`Event` attributes, the following event
attributes are defined:
Attributes
----------
renderer : `RendererBase`
the renderer for the draw event
"""
def __init__(self, name, canvas, renderer):
Event.__init__(self, name, canvas)
self.renderer = renderer
[docs]class ResizeEvent(Event):
"""
An event triggered by a canvas resize
In addition to the :class:`Event` attributes, the following event
attributes are defined:
Attributes
----------
width : scalar
width of the canvas in pixels
height : scalar
height of the canvas in pixels
"""
def __init__(self, name, canvas):
Event.__init__(self, name, canvas)
self.width, self.height = canvas.get_width_height()
[docs]class CloseEvent(Event):
"""
An event triggered by a figure being closed
"""
def __init__(self, name, canvas, guiEvent=None):
Event.__init__(self, name, canvas, guiEvent)
[docs]class LocationEvent(Event):
"""
An event that has a screen location.
The following additional attributes are defined and shown with
their default values.
In addition to the :class:`Event` attributes, the following
event attributes are defined:
Attributes
----------
x : scalar
x position - pixels from left of canvas
y : scalar
y position - pixels from bottom of canvas
inaxes : bool
the :class:`~matplotlib.axes.Axes` instance if mouse is over axes
xdata : scalar
x coord of mouse in data coords
ydata : scalar
y coord of mouse in data coords
"""
lastevent = None # the last event that was triggered before this one
def __init__(self, name, canvas, x, y, guiEvent=None):
"""
*x*, *y* in figure coords, 0,0 = bottom, left
"""
Event.__init__(self, name, canvas, guiEvent=guiEvent)
# x position - pixels from left of canvas
self.x = int(x) if x is not None else x
# y position - pixels from right of canvas
self.y = int(y) if y is not None else y
self.inaxes = None # the Axes instance if mouse us over axes
self.xdata = None # x coord of mouse in data coords
self.ydata = None # y coord of mouse in data coords
if x is None or y is None:
# cannot check if event was in axes if no x,y info
self._update_enter_leave()
return
# Find all axes containing the mouse
if self.canvas.mouse_grabber is None:
axes_list = [a for a in self.canvas.figure.get_axes()
if a.in_axes(self)]
else:
axes_list = [self.canvas.mouse_grabber]
if axes_list:
self.inaxes = cbook._topmost_artist(axes_list)
try:
trans = self.inaxes.transData.inverted()
xdata, ydata = trans.transform_point((x, y))
except ValueError:
pass
else:
self.xdata = xdata
self.ydata = ydata
self._update_enter_leave()
def _update_enter_leave(self):
'process the figure/axes enter leave events'
if LocationEvent.lastevent is not None:
last = LocationEvent.lastevent
if last.inaxes != self.inaxes:
# process axes enter/leave events
try:
if last.inaxes is not None:
last.canvas.callbacks.process('axes_leave_event', last)
except:
pass
# See ticket 2901582.
# I think this is a valid exception to the rule
# against catching all exceptions; if anything goes
# wrong, we simply want to move on and process the
# current event.
if self.inaxes is not None:
self.canvas.callbacks.process('axes_enter_event', self)
else:
# process a figure enter event
if self.inaxes is not None:
self.canvas.callbacks.process('axes_enter_event', self)
LocationEvent.lastevent = self
[docs]class MouseEvent(LocationEvent):
"""
A mouse event ('button_press_event',
'button_release_event',
'scroll_event',
'motion_notify_event').
In addition to the :class:`Event` and :class:`LocationEvent`
attributes, the following attributes are defined:
Attributes
----------
button : {None, 1, 2, 3, 'up', 'down'}
The button pressed. 'up' and 'down' are used for scroll events.
Note that in the nbagg backend, both the middle and right clicks
return 3 since right clicking will bring up the context menu in
some browsers.
key : None or str
The key pressed when the mouse event triggered, e.g. 'shift'.
See `KeyEvent`.
step : scalar
The Number of scroll steps (positive for 'up', negative for 'down').
dblclick : bool
*True* if the event is a double-click.
Examples
--------
Usage::
def on_press(event):
print('you pressed', event.button, event.xdata, event.ydata)
cid = fig.canvas.mpl_connect('button_press_event', on_press)
"""
def __init__(self, name, canvas, x, y, button=None, key=None,
step=0, dblclick=False, guiEvent=None):
"""
x, y in figure coords, 0,0 = bottom, left
button pressed None, 1, 2, 3, 'up', 'down'
"""
LocationEvent.__init__(self, name, canvas, x, y, guiEvent=guiEvent)
self.button = button
self.key = key
self.step = step
self.dblclick = dblclick
def __str__(self):
return ("MPL MouseEvent: xy=(%d,%d) xydata=(%s,%s) button=%s " +
"dblclick=%s inaxes=%s") % (self.x, self.y, self.xdata,
self.ydata, self.button,
self.dblclick, self.inaxes)
[docs]class PickEvent(Event):
"""
a pick event, fired when the user picks a location on the canvas
sufficiently close to an artist.
Attrs: all the :class:`Event` attributes plus
Attributes
----------
mouseevent : `MouseEvent`
the mouse event that generated the pick
artist : `matplotlib.artist.Artist`
the picked artist
other
extra class dependent attrs -- e.g., a
:class:`~matplotlib.lines.Line2D` pick may define different
extra attributes than a
:class:`~matplotlib.collections.PatchCollection` pick event
Examples
--------
Usage::
ax.plot(np.rand(100), 'o', picker=5) # 5 points tolerance
def on_pick(event):
line = event.artist
xdata, ydata = line.get_data()
ind = event.ind
print('on pick line:', np.array([xdata[ind], ydata[ind]]).T)
cid = fig.canvas.mpl_connect('pick_event', on_pick)
"""
def __init__(self, name, canvas, mouseevent, artist,
guiEvent=None, **kwargs):
Event.__init__(self, name, canvas, guiEvent)
self.mouseevent = mouseevent
self.artist = artist
self.__dict__.update(kwargs)
[docs]class KeyEvent(LocationEvent):
"""
A key event (key press, key release).
Attach additional attributes as defined in
:meth:`FigureCanvasBase.mpl_connect`.
In addition to the :class:`Event` and :class:`LocationEvent`
attributes, the following attributes are defined:
Attributes
----------
key : None or str
the key(s) pressed. Could be **None**, a single case sensitive ascii
character ("g", "G", "#", etc.), a special key
("control", "shift", "f1", "up", etc.) or a
combination of the above (e.g., "ctrl+alt+g", "ctrl+alt+G").
Notes
-----
Modifier keys will be prefixed to the pressed key and will be in the order
"ctrl", "alt", "super". The exception to this rule is when the pressed key
is itself a modifier key, therefore "ctrl+alt" and "alt+control" can both
be valid key values.
Examples
--------
Usage::
def on_key(event):
print('you pressed', event.key, event.xdata, event.ydata)
cid = fig.canvas.mpl_connect('key_press_event', on_key)
"""
def __init__(self, name, canvas, key, x=0, y=0, guiEvent=None):
LocationEvent.__init__(self, name, canvas, x, y, guiEvent=guiEvent)
self.key = key
[docs]class FigureCanvasBase(object):
"""
The canvas the figure renders into.
Public attributes
Attributes
----------
figure : `matplotlib.figure.Figure`
A high-level figure instance
"""
events = [
'resize_event',
'draw_event',
'key_press_event',
'key_release_event',
'button_press_event',
'button_release_event',
'scroll_event',
'motion_notify_event',
'pick_event',
'idle_event',
'figure_enter_event',
'figure_leave_event',
'axes_enter_event',
'axes_leave_event',
'close_event'
]
supports_blit = True
fixed_dpi = None
filetypes = _default_filetypes
if _has_pil:
# JPEG support
register_backend('jpg', 'matplotlib.backends.backend_agg',
'Joint Photographic Experts Group')
register_backend('jpeg', 'matplotlib.backends.backend_agg',
'Joint Photographic Experts Group')
# TIFF support
register_backend('tif', 'matplotlib.backends.backend_agg',
'Tagged Image File Format')
register_backend('tiff', 'matplotlib.backends.backend_agg',
'Tagged Image File Format')
def __init__(self, figure):
self._is_idle_drawing = True
self._is_saving = False
figure.set_canvas(self)
self.figure = figure
# a dictionary from event name to a dictionary that maps cid->func
self.callbacks = cbook.CallbackRegistry()
self.widgetlock = widgets.LockDraw()
self._button = None # the button pressed
self._key = None # the key pressed
self._lastx, self._lasty = None, None
self.button_pick_id = self.mpl_connect('button_press_event', self.pick)
self.scroll_pick_id = self.mpl_connect('scroll_event', self.pick)
self.mouse_grabber = None # the axes currently grabbing mouse
self.toolbar = None # NavigationToolbar2 will set me
self._is_idle_drawing = False
@contextmanager
def _idle_draw_cntx(self):
self._is_idle_drawing = True
yield
self._is_idle_drawing = False
[docs] def is_saving(self):
"""
Returns whether the renderer is in the process of saving
to a file, rather than rendering for an on-screen buffer.
"""
return self._is_saving
[docs] @cbook.deprecated("2.2")
def onRemove(self, ev):
"""
Mouse event processor which removes the top artist
under the cursor. Connect this to the 'mouse_press_event'
using::
canvas.mpl_connect('mouse_press_event',canvas.onRemove)
"""
# Find the top artist under the cursor
under = cbook._topmost_artist(self.figure.hitlist(ev))
h = None
if under:
h = under[-1]
# Try deleting that artist, or its parent if you
# can't delete the artist
while h:
if h.remove():
self.draw_idle()
break
parent = None
for p in under:
if h in p.get_children():
parent = p
break
h = parent
[docs] def draw_event(self, renderer):
"""Pass a `DrawEvent` to all functions connected to ``draw_event``."""
s = 'draw_event'
event = DrawEvent(s, self, renderer)
self.callbacks.process(s, event)
[docs] def resize_event(self):
"""Pass a `ResizeEvent` to all functions connected to ``resize_event``.
"""
s = 'resize_event'
event = ResizeEvent(s, self)
self.callbacks.process(s, event)
self.draw_idle()
[docs] def close_event(self, guiEvent=None):
"""Pass a `CloseEvent` to all functions connected to ``close_event``.
"""
s = 'close_event'
try:
event = CloseEvent(s, self, guiEvent=guiEvent)
self.callbacks.process(s, event)
except (TypeError, AttributeError):
pass
# Suppress the TypeError when the python session is being killed.
# It may be that a better solution would be a mechanism to
# disconnect all callbacks upon shutdown.
# AttributeError occurs on OSX with qt4agg upon exiting
# with an open window; 'callbacks' attribute no longer exists.
[docs] def key_press_event(self, key, guiEvent=None):
"""Pass a `KeyEvent` to all functions connected to ``key_press_event``.
"""
self._key = key
s = 'key_press_event'
event = KeyEvent(
s, self, key, self._lastx, self._lasty, guiEvent=guiEvent)
self.callbacks.process(s, event)
[docs] def key_release_event(self, key, guiEvent=None):
"""
Pass a `KeyEvent` to all functions connected to ``key_release_event``.
"""
s = 'key_release_event'
event = KeyEvent(
s, self, key, self._lastx, self._lasty, guiEvent=guiEvent)
self.callbacks.process(s, event)
self._key = None
[docs] def pick_event(self, mouseevent, artist, **kwargs):
"""
This method will be called by artists who are picked and will
fire off :class:`PickEvent` callbacks registered listeners
"""
s = 'pick_event'
event = PickEvent(s, self, mouseevent, artist,
guiEvent=mouseevent.guiEvent,
**kwargs)
self.callbacks.process(s, event)
[docs] def scroll_event(self, x, y, step, guiEvent=None):
"""
Backend derived classes should call this function on any
scroll wheel event. x,y are the canvas coords: 0,0 is lower,
left. button and key are as defined in MouseEvent.
This method will be call all functions connected to the
'scroll_event' with a :class:`MouseEvent` instance.
"""
if step >= 0:
self._button = 'up'
else:
self._button = 'down'
s = 'scroll_event'
mouseevent = MouseEvent(s, self, x, y, self._button, self._key,
step=step, guiEvent=guiEvent)
self.callbacks.process(s, mouseevent)
[docs] def button_press_event(self, x, y, button, dblclick=False, guiEvent=None):
"""
Backend derived classes should call this function on any mouse
button press. x,y are the canvas coords: 0,0 is lower, left.
button and key are as defined in :class:`MouseEvent`.
This method will be call all functions connected to the
'button_press_event' with a :class:`MouseEvent` instance.
"""
self._button = button
s = 'button_press_event'
mouseevent = MouseEvent(s, self, x, y, button, self._key,
dblclick=dblclick, guiEvent=guiEvent)
self.callbacks.process(s, mouseevent)
[docs] def button_release_event(self, x, y, button, guiEvent=None):
"""
Backend derived classes should call this function on any mouse
button release.
This method will call all functions connected to the
'button_release_event' with a :class:`MouseEvent` instance.
Parameters
----------
x : scalar
the canvas coordinates where 0=left
y : scalar
the canvas coordinates where 0=bottom
guiEvent
the native UI event that generated the mpl event
"""
s = 'button_release_event'
event = MouseEvent(s, self, x, y, button, self._key, guiEvent=guiEvent)
self.callbacks.process(s, event)
self._button = None
[docs] def motion_notify_event(self, x, y, guiEvent=None):
"""
Backend derived classes should call this function on any
motion-notify-event.
This method will call all functions connected to the
'motion_notify_event' with a :class:`MouseEvent` instance.
Parameters
----------
x : scalar
the canvas coordinates where 0=left
y : scalar
the canvas coordinates where 0=bottom
guiEvent
the native UI event that generated the mpl event
"""
self._lastx, self._lasty = x, y
s = 'motion_notify_event'
event = MouseEvent(s, self, x, y, self._button, self._key,
guiEvent=guiEvent)
self.callbacks.process(s, event)
[docs] def leave_notify_event(self, guiEvent=None):
"""
Backend derived classes should call this function when leaving
canvas
Parameters
----------
guiEvent
the native UI event that generated the mpl event
"""
self.callbacks.process('figure_leave_event', LocationEvent.lastevent)
LocationEvent.lastevent = None
self._lastx, self._lasty = None, None
[docs] def enter_notify_event(self, guiEvent=None, xy=None):
"""
Backend derived classes should call this function when entering
canvas
Parameters
----------
guiEvent
the native UI event that generated the mpl event
xy : (float, float)
the coordinate location of the pointer when the canvas is
entered
"""
if xy is not None:
x, y = xy
self._lastx, self._lasty = x, y
else:
x = None
y = None
cbook.warn_deprecated('3.0', 'enter_notify_event expects a '
'location but '
'your backend did not pass one.')
event = LocationEvent('figure_enter_event', self, x, y, guiEvent)
self.callbacks.process('figure_enter_event', event)
[docs] def grab_mouse(self, ax):
"""
Set the child axes which are currently grabbing the mouse events.
Usually called by the widgets themselves.
It is an error to call this if the mouse is already grabbed by
another axes.
"""
if self.mouse_grabber not in (None, ax):
raise RuntimeError("Another Axes already grabs mouse input")
self.mouse_grabber = ax
[docs] def release_mouse(self, ax):
"""
Release the mouse grab held by the axes, ax.
Usually called by the widgets.
It is ok to call this even if you ax doesn't have the mouse
grab currently.
"""
if self.mouse_grabber is ax:
self.mouse_grabber = None
[docs] def draw_idle(self, *args, **kwargs):
"""
:meth:`draw` only if idle; defaults to draw but backends can override
"""
if not self._is_idle_drawing:
with self._idle_draw_cntx():
self.draw(*args, **kwargs)
[docs] def draw_cursor(self, event):
"""
Draw a cursor in the event.axes if inaxes is not None. Use
native GUI drawing for efficiency if possible
"""
[docs] def get_width_height(self):
"""
Return the figure width and height in points or pixels
(depending on the backend), truncated to integers
"""
return int(self.figure.bbox.width), int(self.figure.bbox.height)
[docs] @classmethod
def get_supported_filetypes(cls):
"""Return dict of savefig file formats supported by this backend"""
return cls.filetypes
[docs] @classmethod
def get_supported_filetypes_grouped(cls):
"""Return a dict of savefig file formats supported by this backend,
where the keys are a file type name, such as 'Joint Photographic
Experts Group', and the values are a list of filename extensions used
for that filetype, such as ['jpg', 'jpeg']."""
groupings = {}
for ext, name in cls.filetypes.items():
groupings.setdefault(name, []).append(ext)
groupings[name].sort()
return groupings
def _get_output_canvas(self, fmt):
"""
Return a canvas suitable for saving figures to a specified file format.
If necessary, this function will switch to a registered backend that
supports the format.
"""
# Return the current canvas if it supports the requested format.
if hasattr(self, 'print_{}'.format(fmt)):
return self
# Return a default canvas for the requested format, if it exists.
canvas_class = get_registered_canvas_class(fmt)
if canvas_class:
return self.switch_backends(canvas_class)
# Else report error for unsupported format.
raise ValueError(
"Format {!r} is not supported (supported formats: {})"
.format(fmt, ", ".join(sorted(self.get_supported_filetypes()))))
[docs] def print_figure(self, filename, dpi=None, facecolor=None, edgecolor=None,
orientation='portrait', format=None,
*, bbox_inches=None, **kwargs):
"""
Render the figure to hardcopy. Set the figure patch face and edge
colors. This is useful because some of the GUIs have a gray figure
face color background and you'll probably want to override this on
hardcopy.
Parameters
----------
filename
can also be a file object on image backends
orientation : {'landscape', 'portrait'}, optional
only currently applies to PostScript printing.
dpi : scalar, optional
the dots per inch to save the figure in; if None, use savefig.dpi
facecolor : color spec or None, optional
the facecolor of the figure; if None, defaults to savefig.facecolor
edgecolor : color spec or None, optional
the edgecolor of the figure; if None, defaults to savefig.edgecolor
format : str, optional
when set, forcibly set the file format to save to
bbox_inches : str or `~matplotlib.transforms.Bbox`, optional
Bbox in inches. Only the given portion of the figure is
saved. If 'tight', try to figure out the tight bbox of
the figure. If None, use savefig.bbox
pad_inches : scalar, optional
Amount of padding around the figure when bbox_inches is
'tight'. If None, use savefig.pad_inches
bbox_extra_artists : list of `~matplotlib.artist.Artist`, optional
A list of extra artists that will be considered when the
tight bbox is calculated.
"""
if format is None:
# get format from filename, or from backend's default filetype
if isinstance(filename, getattr(os, "PathLike", ())):
filename = os.fspath(filename)
if isinstance(filename, str):
format = os.path.splitext(filename)[1][1:]
if format is None or format == '':
format = self.get_default_filetype()
if isinstance(filename, str):
filename = filename.rstrip('.') + '.' + format
format = format.lower()
# get canvas object and print method for format
canvas = self._get_output_canvas(format)
print_method = getattr(canvas, 'print_%s' % format)
if dpi is None:
dpi = rcParams['savefig.dpi']
if dpi == 'figure':
dpi = getattr(self.figure, '_original_dpi', self.figure.dpi)
# Remove the figure manager, if any, to avoid resizing the GUI widget.
# Some code (e.g. Figure.show) differentiates between having *no*
# manager and a *None* manager, which should be fixed at some point,
# but this should be fine.
with cbook._setattr_cm(self, _is_saving=True, manager=None), \
cbook._setattr_cm(self.figure, dpi=dpi):
if facecolor is None:
facecolor = rcParams['savefig.facecolor']
if edgecolor is None:
edgecolor = rcParams['savefig.edgecolor']
origfacecolor = self.figure.get_facecolor()
origedgecolor = self.figure.get_edgecolor()
self.figure.dpi = dpi
self.figure.set_facecolor(facecolor)
self.figure.set_edgecolor(edgecolor)
if bbox_inches is None:
bbox_inches = rcParams['savefig.bbox']
if bbox_inches:
# call adjust_bbox to save only the given area
if bbox_inches == "tight":
# When bbox_inches == "tight", it saves the figure twice.
# The first save command (to a BytesIO) is just to estimate
# the bounding box of the figure.
result = print_method(
io.BytesIO(),
dpi=dpi,
facecolor=facecolor,
edgecolor=edgecolor,
orientation=orientation,
dryrun=True,
**kwargs)
renderer = self.figure._cachedRenderer
bbox_artists = kwargs.pop("bbox_extra_artists", None)
bbox_inches = self.figure.get_tightbbox(renderer,
bbox_extra_artists=bbox_artists)
pad = kwargs.pop("pad_inches", None)
if pad is None:
pad = rcParams['savefig.pad_inches']
bbox_inches = bbox_inches.padded(pad)
restore_bbox = tight_bbox.adjust_bbox(self.figure, bbox_inches,
canvas.fixed_dpi)
_bbox_inches_restore = (bbox_inches, restore_bbox)
else:
_bbox_inches_restore = None
try:
result = print_method(
filename,
dpi=dpi,
facecolor=facecolor,
edgecolor=edgecolor,
orientation=orientation,
bbox_inches_restore=_bbox_inches_restore,
**kwargs)
finally:
if bbox_inches and restore_bbox:
restore_bbox()
self.figure.set_facecolor(origfacecolor)
self.figure.set_edgecolor(origedgecolor)
self.figure.set_canvas(self)
return result
[docs] @classmethod
def get_default_filetype(cls):
"""
Get the default savefig file format as specified in rcParam
``savefig.format``. Returned string excludes period. Overridden
in backends that only support a single file type.
"""
return rcParams['savefig.format']
[docs] def get_window_title(self):
"""
Get the title text of the window containing the figure.
Return None if there is no window (e.g., a PS backend).
"""
if hasattr(self, "manager"):
return self.manager.get_window_title()
[docs] def set_window_title(self, title):
"""
Set the title text of the window containing the figure. Note that
this has no effect if there is no window (e.g., a PS backend).
"""
if hasattr(self, "manager"):
self.manager.set_window_title(title)
[docs] def get_default_filename(self):
"""
Return a string, which includes extension, suitable for use as
a default filename.
"""
default_basename = self.get_window_title() or 'image'
default_basename = default_basename.replace(' ', '_')
default_filetype = self.get_default_filetype()
default_filename = default_basename + '.' + default_filetype
return default_filename
[docs] def switch_backends(self, FigureCanvasClass):
"""
Instantiate an instance of FigureCanvasClass
This is used for backend switching, e.g., to instantiate a
FigureCanvasPS from a FigureCanvasGTK. Note, deep copying is
not done, so any changes to one of the instances (e.g., setting
figure size or line props), will be reflected in the other
"""
newCanvas = FigureCanvasClass(self.figure)
newCanvas._is_saving = self._is_saving
return newCanvas
[docs] def mpl_connect(self, s, func):
"""
Connect event with string *s* to *func*. The signature of *func* is::
def func(event)
where event is a :class:`matplotlib.backend_bases.Event`. The
following events are recognized
- 'button_press_event'
- 'button_release_event'
- 'draw_event'
- 'key_press_event'
- 'key_release_event'
- 'motion_notify_event'
- 'pick_event'
- 'resize_event'
- 'scroll_event'
- 'figure_enter_event',
- 'figure_leave_event',
- 'axes_enter_event',
- 'axes_leave_event'
- 'close_event'
For the location events (button and key press/release), if the
mouse is over the axes, the variable ``event.inaxes`` will be
set to the :class:`~matplotlib.axes.Axes` the event occurs is
over, and additionally, the variables ``event.xdata`` and
``event.ydata`` will be defined. This is the mouse location
in data coords. See
:class:`~matplotlib.backend_bases.KeyEvent` and
:class:`~matplotlib.backend_bases.MouseEvent` for more info.
Return value is a connection id that can be used with
:meth:`~matplotlib.backend_bases.Event.mpl_disconnect`.
Examples
--------
Usage::
def on_press(event):
print('you pressed', event.button, event.xdata, event.ydata)
cid = canvas.mpl_connect('button_press_event', on_press)
"""
return self.callbacks.connect(s, func)
[docs] def mpl_disconnect(self, cid):
"""
Disconnect callback id cid
Examples
--------
Usage::
cid = canvas.mpl_connect('button_press_event', on_press)
#...later
canvas.mpl_disconnect(cid)
"""
return self.callbacks.disconnect(cid)
[docs] def new_timer(self, *args, **kwargs):
"""
Creates a new backend-specific subclass of
:class:`backend_bases.Timer`. This is useful for getting periodic
events through the backend's native event loop. Implemented only for
backends with GUIs.
Other Parameters
----------------
interval : scalar
Timer interval in milliseconds
callbacks : List[Tuple[callable, Tuple, Dict]]
Sequence of (func, args, kwargs) where ``func(*args, **kwargs)``
will be executed by the timer every *interval*.
callbacks which return ``False`` or ``0`` will be removed from the
timer.
Examples
--------
>>> timer = fig.canvas.new_timer(callbacks=[(f1, (1, ), {'a': 3}),])
"""
return TimerBase(*args, **kwargs)
[docs] def flush_events(self):
"""Flush the GUI events for the figure.
Interactive backends need to reimplement this method.
"""
[docs] def start_event_loop(self, timeout=0):
"""Start a blocking event loop.
Such an event loop is used by interactive functions, such as `ginput`
and `waitforbuttonpress`, to wait for events.
The event loop blocks until a callback function triggers
`stop_event_loop`, or *timeout* is reached.
If *timeout* is negative, never timeout.
Only interactive backends need to reimplement this method and it relies
on `flush_events` being properly implemented.
Interactive backends should implement this in a more native way.
"""
if timeout <= 0:
timeout = np.inf
timestep = 0.01
counter = 0
self._looping = True
while self._looping and counter * timestep < timeout:
self.flush_events()
time.sleep(timestep)
counter += 1
[docs] def stop_event_loop(self):
"""Stop the current blocking event loop.
Interactive backends need to reimplement this to match
`start_event_loop`
"""
self._looping = False
[docs]def key_press_handler(event, canvas, toolbar=None):
"""
Implement the default mpl key bindings for the canvas and toolbar
described at :ref:`key-event-handling`
Parameters
----------
event : :class:`KeyEvent`
a key press/release event
canvas : :class:`FigureCanvasBase`
the backend-specific canvas instance
toolbar : :class:`NavigationToolbar2`
the navigation cursor toolbar
"""
# these bindings happen whether you are over an axes or not
if event.key is None:
return
# Load key-mappings from rcParams.
fullscreen_keys = rcParams['keymap.fullscreen']
home_keys = rcParams['keymap.home']
back_keys = rcParams['keymap.back']
forward_keys = rcParams['keymap.forward']
pan_keys = rcParams['keymap.pan']
zoom_keys = rcParams['keymap.zoom']
save_keys = rcParams['keymap.save']
quit_keys = rcParams['keymap.quit']
grid_keys = rcParams['keymap.grid']
grid_minor_keys = rcParams['keymap.grid_minor']
toggle_yscale_keys = rcParams['keymap.yscale']
toggle_xscale_keys = rcParams['keymap.xscale']
all_keys = rcParams['keymap.all_axes']
# toggle fullscreen mode ('f', 'ctrl + f')
if event.key in fullscreen_keys:
try:
canvas.manager.full_screen_toggle()
except AttributeError:
pass
# quit the figure (default key 'ctrl+w')
if event.key in quit_keys:
Gcf.destroy_fig(canvas.figure)
if toolbar is not None:
# home or reset mnemonic (default key 'h', 'home' and 'r')
if event.key in home_keys:
toolbar.home()
# forward / backward keys to enable left handed quick navigation
# (default key for backward: 'left', 'backspace' and 'c')
elif event.key in back_keys:
toolbar.back()
# (default key for forward: 'right' and 'v')
elif event.key in forward_keys:
toolbar.forward()
# pan mnemonic (default key 'p')
elif event.key in pan_keys:
toolbar.pan()
toolbar._set_cursor(event)
# zoom mnemonic (default key 'o')
elif event.key in zoom_keys:
toolbar.zoom()
toolbar._set_cursor(event)
# saving current figure (default key 's')
elif event.key in save_keys:
toolbar.save_figure()
if event.inaxes is None:
return
# these bindings require the mouse to be over an axes to trigger
def _get_uniform_gridstate(ticks):
# Return True/False if all grid lines are on or off, None if they are
# not all in the same state.
if all(tick.gridOn for tick in ticks):
return True
elif not any(tick.gridOn for tick in ticks):
return False
else:
return None
ax = event.inaxes
# toggle major grids in current axes (default key 'g')
# Both here and below (for 'G'), we do nothing if *any* grid (major or
# minor, x or y) is not in a uniform state, to avoid messing up user
# customization.
if (event.key in grid_keys
# Exclude minor grids not in a uniform state.
and None not in [_get_uniform_gridstate(ax.xaxis.minorTicks),
_get_uniform_gridstate(ax.yaxis.minorTicks)]):
x_state = _get_uniform_gridstate(ax.xaxis.majorTicks)
y_state = _get_uniform_gridstate(ax.yaxis.majorTicks)
cycle = [(False, False), (True, False), (True, True), (False, True)]
try:
x_state, y_state = (
cycle[(cycle.index((x_state, y_state)) + 1) % len(cycle)])
except ValueError:
# Exclude major grids not in a uniform state.
pass
else:
# If turning major grids off, also turn minor grids off.
ax.grid(x_state, which="major" if x_state else "both", axis="x")
ax.grid(y_state, which="major" if y_state else "both", axis="y")
canvas.draw_idle()
# toggle major and minor grids in current axes (default key 'G')
if (event.key in grid_minor_keys
# Exclude major grids not in a uniform state.
and None not in [_get_uniform_gridstate(ax.xaxis.majorTicks),
_get_uniform_gridstate(ax.yaxis.majorTicks)]):
x_state = _get_uniform_gridstate(ax.xaxis.minorTicks)
y_state = _get_uniform_gridstate(ax.yaxis.minorTicks)
cycle = [(False, False), (True, False), (True, True), (False, True)]
try:
x_state, y_state = (
cycle[(cycle.index((x_state, y_state)) + 1) % len(cycle)])
except ValueError:
# Exclude minor grids not in a uniform state.
pass
else:
ax.grid(x_state, which="both", axis="x")
ax.grid(y_state, which="both", axis="y")
canvas.draw_idle()
# toggle scaling of y-axes between 'log and 'linear' (default key 'l')
elif event.key in toggle_yscale_keys:
scale = ax.get_yscale()
if scale == 'log':
ax.set_yscale('linear')
ax.figure.canvas.draw_idle()
elif scale == 'linear':
try:
ax.set_yscale('log')
except ValueError as exc:
warnings.warn(str(exc))
ax.set_yscale('linear')
ax.figure.canvas.draw_idle()
# toggle scaling of x-axes between 'log and 'linear' (default key 'k')
elif event.key in toggle_xscale_keys:
scalex = ax.get_xscale()
if scalex == 'log':
ax.set_xscale('linear')
ax.figure.canvas.draw_idle()
elif scalex == 'linear':
try:
ax.set_xscale('log')
except ValueError as exc:
warnings.warn(str(exc))
ax.set_xscale('linear')
ax.figure.canvas.draw_idle()
elif (event.key.isdigit() and event.key != '0') or event.key in all_keys:
# keys in list 'all' enables all axes (default key 'a'),
# otherwise if key is a number only enable this particular axes
# if it was the axes, where the event was raised
if event.key not in all_keys:
n = int(event.key) - 1
for i, a in enumerate(canvas.figure.get_axes()):
# consider axes, in which the event was raised
# FIXME: Why only this axes?
if (event.x is not None and event.y is not None
and a.in_axes(event)):
if event.key in all_keys:
a.set_navigate(True)
else:
a.set_navigate(i == n)
[docs]class FigureManagerBase(object):
"""
Helper class for pyplot mode, wraps everything up into a neat bundle
Attributes
----------
canvas : :class:`FigureCanvasBase`
The backend-specific canvas instance
num : int or str
The figure number
key_press_handler_id : int
The default key handler cid, when using the toolmanager. Can be used
to disable default key press handling ::
figure.canvas.mpl_disconnect(
figure.canvas.manager.key_press_handler_id)
"""
def __init__(self, canvas, num):
self.canvas = canvas
canvas.manager = self # store a pointer to parent
self.num = num
self.key_press_handler_id = None
if rcParams['toolbar'] != 'toolmanager':
self.key_press_handler_id = self.canvas.mpl_connect(
'key_press_event',
self.key_press)
self.toolmanager = None
self.toolbar = None
@self.canvas.figure.add_axobserver
def notify_axes_change(fig):
# Called whenever the current axes is changed.
if self.toolmanager is None and self.toolbar is not None:
self.toolbar.update()
[docs] def show(self):
"""
For GUI backends, show the figure window and redraw.
For non-GUI backends, raise an exception to be caught
by :meth:`~matplotlib.figure.Figure.show`, for an
optional warning.
"""
raise NonGuiException()
[docs] def key_press(self, event):
"""
Implement the default mpl key bindings defined at
:ref:`key-event-handling`
"""
if rcParams['toolbar'] != 'toolmanager':
key_press_handler(event, self.canvas, self.canvas.toolbar)
[docs] @cbook.deprecated("2.2")
def show_popup(self, msg):
"""Display message in a popup -- GUI only."""
[docs] def get_window_title(self):
"""Get the title text of the window containing the figure.
Return None for non-GUI (e.g., PS) backends.
"""
return 'image'
[docs] def set_window_title(self, title):
"""Set the title text of the window containing the figure.
This has no effect for non-GUI (e.g., PS) backends.
"""
cursors = tools.cursors
[docs]class ToolContainerBase(object):
"""
Base class for all tool containers, e.g. toolbars.
Attributes
----------
toolmanager : `ToolManager`
The tools with which this `ToolContainer` wants to communicate.
"""
_icon_extension = '.png'
"""
Toolcontainer button icon image format extension
**String**: Image extension
"""
def __init__(self, toolmanager):
self.toolmanager = toolmanager
self.toolmanager.toolmanager_connect('tool_removed_event',
self._remove_tool_cbk)
def _tool_toggled_cbk(self, event):
"""
Captures the 'tool_trigger_[name]'
This only gets used for toggled tools
"""
self.toggle_toolitem(event.tool.name, event.tool.toggled)
[docs] def add_tool(self, tool, group, position=-1):
"""
Adds a tool to this container
Parameters
----------
tool : tool_like
The tool to add, see `ToolManager.get_tool`.
group : str
The name of the group to add this tool to.
position : int (optional)
The position within the group to place this tool. Defaults to end.
"""
tool = self.toolmanager.get_tool(tool)
image = self._get_image_filename(tool.image)
toggle = getattr(tool, 'toggled', None) is not None
self.add_toolitem(tool.name, group, position,
image, tool.description, toggle)
if toggle:
self.toolmanager.toolmanager_connect('tool_trigger_%s' % tool.name,
self._tool_toggled_cbk)
# If initially toggled
if tool.toggled:
self.toggle_toolitem(tool.name, True)
def _remove_tool_cbk(self, event):
"""Captures the 'tool_removed_event' signal and removes the tool."""
self.remove_toolitem(event.tool.name)
def _get_image_filename(self, image):
"""Find the image based on its name."""
if not image:
return None
basedir = os.path.join(rcParams['datapath'], 'images')
possible_images = (
image,
image + self._icon_extension,
os.path.join(basedir, image),
os.path.join(basedir, image) + self._icon_extension)
for fname in possible_images:
if os.path.isfile(fname):
return fname
[docs] def trigger_tool(self, name):
"""
Trigger the tool
Parameters
----------
name : String
Name (id) of the tool triggered from within the container
"""
self.toolmanager.trigger_tool(name, sender=self)
[docs] def add_toolitem(self, name, group, position, image, description, toggle):
"""
Add a toolitem to the container
This method must get implemented per backend
The callback associated with the button click event,
must be **EXACTLY** `self.trigger_tool(name)`
Parameters
----------
name : string
Name of the tool to add, this gets used as the tool's ID and as the
default label of the buttons
group : String
Name of the group that this tool belongs to
position : Int
Position of the tool within its group, if -1 it goes at the End
image_file : String
Filename of the image for the button or `None`
description : String
Description of the tool, used for the tooltips
toggle : Bool
* `True` : The button is a toggle (change the pressed/unpressed
state between consecutive clicks)
* `False` : The button is a normal button (returns to unpressed
state after release)
"""
raise NotImplementedError
[docs] def toggle_toolitem(self, name, toggled):
"""
Toggle the toolitem without firing event
Parameters
----------
name : String
Id of the tool to toggle
toggled : bool
Whether to set this tool as toggled or not.
"""
raise NotImplementedError
[docs] def remove_toolitem(self, name):
"""
Remove a toolitem from the `ToolContainer`
This method must get implemented per backend
Called when `ToolManager` emits a `tool_removed_event`
Parameters
----------
name : string
Name of the tool to remove
"""
raise NotImplementedError
[docs]class StatusbarBase(object):
"""Base class for the statusbar"""
def __init__(self, toolmanager):
self.toolmanager = toolmanager
self.toolmanager.toolmanager_connect('tool_message_event',
self._message_cbk)
def _message_cbk(self, event):
"""Captures the 'tool_message_event' and set the message"""
self.set_message(event.message)
[docs] def set_message(self, s):
"""
Display a message on toolbar or in status bar
Parameters
----------
s : str
Message text
"""
pass
class _Backend(object):
# A backend can be defined by using the following pattern:
#
# @_Backend.export
# class FooBackend(_Backend):
# # override the attributes and methods documented below.
# Set to one of {"qt5", "qt4", "gtk3", "wx", "tk", "macosx"} if an
# interactive framework is required, or None otherwise.
required_interactive_framework = None
# `backend_version` may be overridden by the subclass.
backend_version = "unknown"
# The `FigureCanvas` class must be defined.
FigureCanvas = None
# For interactive backends, the `FigureManager` class must be overridden.
FigureManager = FigureManagerBase
# The following methods must be left as None for non-interactive backends.
# For interactive backends, `trigger_manager_draw` should be a function
# taking a manager as argument and triggering a canvas draw, and `mainloop`
# should be a function taking no argument and starting the backend main
# loop.
trigger_manager_draw = None
mainloop = None
# The following methods will be automatically defined and exported, but
# can be overridden.
@classmethod
def new_figure_manager(cls, num, *args, **kwargs):
"""Create a new figure manager instance.
"""
# This import needs to happen here due to circular imports.
from matplotlib.figure import Figure
fig_cls = kwargs.pop('FigureClass', Figure)
fig = fig_cls(*args, **kwargs)
return cls.new_figure_manager_given_figure(num, fig)
@classmethod
def new_figure_manager_given_figure(cls, num, figure):
"""Create a new figure manager instance for the given figure.
"""
canvas = cls.FigureCanvas(figure)
manager = cls.FigureManager(canvas, num)
return manager
@classmethod
def draw_if_interactive(cls):
if cls.trigger_manager_draw is not None and is_interactive():
manager = Gcf.get_active()
if manager:
cls.trigger_manager_draw(manager)
@classmethod
def show(cls, block=None):
"""Show all figures.
`show` blocks by calling `mainloop` if *block* is ``True``, or if it
is ``None`` and we are neither in IPython's ``%pylab`` mode, nor in
`interactive` mode.
"""
managers = Gcf.get_all_fig_managers()
if not managers:
return
for manager in managers:
# Emits a warning if the backend is non-interactive.
manager.canvas.figure.show()
if cls.mainloop is None:
return
if block is None:
# Hack: Are we in IPython's pylab mode?
from matplotlib import pyplot
try:
# IPython versions >= 0.10 tack the _needmain attribute onto
# pyplot.show, and always set it to False, when in %pylab mode.
ipython_pylab = not pyplot.show._needmain
except AttributeError:
ipython_pylab = False
block = not ipython_pylab and not is_interactive()
# TODO: The above is a hack to get the WebAgg backend working with
# ipython's `%pylab` mode until proper integration is implemented.
if get_backend() == "WebAgg":
block = True
if block:
cls.mainloop()
# This method is the one actually exporting the required methods.
@staticmethod
def export(cls):
for name in ["required_interactive_framework",
"backend_version",
"FigureCanvas",
"FigureManager",
"new_figure_manager",
"new_figure_manager_given_figure",
"draw_if_interactive",
"show"]:
setattr(sys.modules[cls.__module__], name, getattr(cls, name))
# For back-compatibility, generate a shim `Show` class.
class Show(ShowBase):
def mainloop(self):
return cls.mainloop()
setattr(sys.modules[cls.__module__], "Show", Show)
return cls
[docs]class ShowBase(_Backend):
"""
Simple base class to generate a show() callable in backends.
Subclass must override mainloop() method.
"""
def __call__(self, block=None):
return self.show(block=block)