matplotlib/lib/matplotlib/backend_bases.py at master · flothesof/matplotlib · GitHub

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"""

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 __future__ import (absolute_import, division, print_function,

unicode_literals)

from contextlib import contextmanager

from matplotlib.externals import six

from matplotlib.externals.six.moves import xrange

import os

import sys

import warnings

import time

import io

import numpy as np

import matplotlib.cbook as cbook

import matplotlib.colors as colors

import matplotlib.transforms as transforms

import matplotlib.widgets as widgets

#import matplotlib.path as path

from matplotlib import rcParams

from matplotlib import is_interactive

from matplotlib import get_backend

from matplotlib._pylab_helpers import Gcf

from matplotlib.transforms import Bbox, TransformedBbox, Affine2D

import matplotlib.tight_bbox as tight_bbox

import matplotlib.textpath as textpath

from matplotlib.path import Path

from matplotlib.cbook import mplDeprecation, warn_deprecated

import matplotlib.backend_tools as tools

try:

from importlib import import_module

except:

# simple python 2.6 implementation (no relative imports)

def import_module(name):

__import__(name)

return sys.modules[name]

try:

from PIL import Image

_has_pil = True

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',

}

def register_backend(format, backend, description=None):

"""

format : str

File extention

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

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 cbook.is_string_like(backend_class):

backend_class = import_module(backend_class).FigureCanvas

_default_backends[format] = backend_class

return backend_class

class ShowBase(object):

"""

Simple base class to generate a show() callable in backends.

Subclass must override mainloop() method.

"""

def __call__(self, block=None):

"""

Show all figures. If *block* is not None, then

it is a boolean that overrides all other factors

determining whether show blocks by calling mainloop().

The other factors are:

it does not block if run inside ipython's "%pylab" mode

it does not block in interactive mode.

"""

managers = Gcf.get_all_fig_managers()

if not managers:

return

for manager in managers:

manager.show()

if block is not None:

if block:

self.mainloop()

return

else:

return

# Hack: determine at runtime whether we are

# inside ipython in pylab mode.

from matplotlib import pyplot

try:

ipython_pylab = not pyplot.show._needmain

# IPython versions >= 0.10 tack the _needmain

# attribute onto pyplot.show, and always set

# it to False, when in %pylab mode.

ipython_pylab = ipython_pylab and get_backend() != 'WebAgg'

# TODO: The above is a hack to get the WebAgg backend

# working with ipython's `%pylab` mode until proper

# integration is implemented.

except AttributeError:

ipython_pylab = False

# Leave the following as a separate step in case we

# want to control this behavior with an rcParam.

if ipython_pylab:

return

if not is_interactive() or get_backend() == 'WebAgg':

self.mainloop()

def mainloop(self):

pass

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()

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`.

"""

pass

def close_group(self, s):

"""

Close a grouping element with label *s*

Is only currently used by :mod:`~matplotlib.backends.backend_svg`

"""

pass

def draw_path(self, gc, path, transform, rgbFace=None):

"""

Draws a :class:`~matplotlib.path.Path` instance using the

given affine transform.

"""

raise NotImplementedError

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.

*gc*

the :class:`GraphicsContextBase` instance

*marker_trans*

is an affine transform applied to the marker.

*trans*

is an affine transform applied to the path.

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.

"""

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)

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)

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()], np.float_)

return self.draw_path_collection(

gc, master_transform, paths, [], offsets, offsetTrans, facecolors,

edgecolors, linewidths, [], [antialiased], [None], 'screen')

def draw_gouraud_triangle(self, gc, points, colors, transform):

"""

Draw a Gouraud-shaded triangle.

*points* is a 3x2 array of (x, y) points for the triangle.

*colors* is a 3x4 array of RGBA colors for each point of the

triangle.

*transform* is an affine transform to apply to the points.

"""

raise NotImplementedError

def draw_gouraud_triangles(self, gc, triangles_array, colors_array,

transform):

"""

Draws a series of Gouraud triangles.

*points* is a Nx3x2 array of (x, y) points for the trianglex.

*colors* is a Nx3x4 array of RGBA colors for each point of the

triangles.

*transform* is 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-efficent :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 xrange(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) == 0 and 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-efficent :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 xrange(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()

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

def draw_image(self, gc, x, y, im):

"""

Draw the image instance into the current axes;

*gc*

a GraphicsContext containing clipping information

*x*

is the distance in pixels from the left hand side of the canvas.

*y*

the distance from the origin. That is, if origin is

upper, y is the distance from top. If origin is lower, y

is the distance from bottom

*im*

the :class:`matplotlib._image.Image` instance

"""

raise NotImplementedError

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

def option_scale_image(self):

"""

override this method for renderers that support arbitrary

scaling of image (most of the vector backend).

"""

return False

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")

def draw_text(self, gc, x, y, s, prop, angle, ismath=False, mtext=None):

"""

Draw the text instance

*gc*

the :class:`GraphicsContextBase` instance

*x*

the x location of the text in display coords

*y*

the y location of the text baseline in display coords

*s*

the text string

*prop*

a :class:`matplotlib.font_manager.FontProperties` instance

*angle*

the rotation angle in degrees

*mtext*

a :class:`matplotlib.text.Text` instance

**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

*prop*

font property

*s*

text to be converted

*usetex*

If True, use matplotlib usetex mode.

*ismath*

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 = angle / 180. * 3.141592

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.

*prop*

font property

*s*

text to be converted

*usetex*

If True, use matplotlib usetex mode.

*ismath*

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)

def get_text_width_height_descent(self, s, prop, ismath):

"""

get the width and height, and the offset from the bottom to the

baseline (descent), 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

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

def get_canvas_width_height(self):

'return the canvas width and height in display coords'

return 1, 1

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

def new_gc(self):

"""

Return an instance of a :class:`GraphicsContextBase`

"""

return GraphicsContextBase()

def points_to_pixels(self, points):

"""

Convert points to display units

*points*

a float or a numpy array of float

return points converted to pixels

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

"""

return points

def strip_math(self, s):

return cbook.strip_math(s)

def start_rasterizing(self):

"""

Used in MixedModeRenderer. Switch to the raster renderer.

"""

pass

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.

"""

pass

def start_filter(self):

"""

Used in AggRenderer. Switch to a temporary renderer for image

filtering effects.

"""

pass

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.

"""

pass

class GraphicsContextBase(object):

"""

An abstract base class that provides color, line styles, etc...

"""

# a mapping from dash styles to suggested offset, dash pairs

dashd = {

'solid': (None, None),

'dashed': (0, (6.0, 6.0)),

'dashdot': (0, (3.0, 5.0, 1.0, 5.0)),

'dotted': (0, (1.0, 3.0)),

}

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._url = None

self._gid = None

self._snap = None

self._sketch = None

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._url = gc._url

self._gid = gc._gid

self._snap = gc._snap

self._sketch = gc._sketch

def restore(self):

"""

Restore the graphics context from the stack - needed only

for backends that save graphics contexts on a stack

"""

pass

def get_alpha(self):

"""

Return the alpha value used for blending - not supported on

all backends

"""

return self._alpha

def get_antialiased(self):

"Return true if the object should try to do antialiased rendering"

return self._antialiased

def get_capstyle(self):

"""

Return the capstyle as a string in ('butt', 'round', 'projecting')

"""

return self._capstyle

def get_clip_rectangle(self):

"""

Return the clip rectangle as a :class:`~matplotlib.transforms.Bbox`

instance

"""

return self._cliprect

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

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

<http://www-cdf.fnal.gov/offline/PostScript/BLUEBOOK.PDF>`_

for more info.

Default value is None

"""

return self._dashes

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

def get_joinstyle(self):

"""

Return the line join style as one of ('miter', 'round', 'bevel')

"""

return self._joinstyle

def get_linestyle(self, style):

"""

Return the linestyle: one of ('solid', 'dashed', 'dashdot',

'dotted').

"""

return self._linestyle

def get_linewidth(self):

"""

Return the line width in points as a scalar

"""

return self._linewidth

def get_rgb(self):

"""

returns a tuple of three or four floats from 0-1.

"""

return self._rgb

def get_url(self):

"""

returns a url if one is set, None otherwise

"""

return self._url

def get_gid(self):

"""

Return the object identifier if one is set, None otherwise.

"""

return self._gid

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

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)

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

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)

def set_clip_rectangle(self, rectangle):

"""

Set the clip rectangle with sequence (left, bottom, width, height)

"""

self._cliprect = rectangle

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):

msg = ("Path should be a matplotlib.transforms.TransformedPath"

"instance.")

raise ValueError(msg)

self._clippath = path

def set_dashes(self, dash_offset, dash_list):

"""

Set the dash style for the gc.

*dash_offset*

is the offset (usually 0).

*dash_list*

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):

View remainder of file in raw view

matplotlib/lib/matplotlib/backend_bases.py at master · flothesof/matplotlib · GitHub

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