Version 3.0.2
matplotlib
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Source code for matplotlib.backend_bases

"""
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 strip_math(self, s): return cbook.strip_math(s)
[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_url(self): """ returns a url if one is set, None otherwise """ return self._url
[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_linewidth(self, w): """ Set the linewidth in points """ self._linewidth = float(w)
[docs] def set_url(self, url): """ Sets the url for links in compatible backends """ self._url = url
[docs] def set_gid(self, id): """ Sets the id. """ self._gid = id
[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 set_hatch(self, hatch): """ Sets the hatch style for filling """ self._hatch = hatch
[docs] def get_hatch(self): """ Gets the current hatch style """ return self._hatch
[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()
[docs] def stop(self): ''' Stop the timer. ''' self._timer_stop()
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 pick(self, mouseevent): if not self.widgetlock.locked(): self.figure.pick(mouseevent)
[docs] def blit(self, bbox=None): """Blit the canvas in bbox (default entire canvas)."""
[docs] def resize(self, w, h): """Set the canvas size in pixels."""
[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(self, *args, **kwargs): """Render the :class:`~matplotlib.figure.Figure`."""
[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 NonGuiException(Exception): pass
[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 destroy(self): pass
[docs] def full_screen_toggle(self): pass
[docs] def resize(self, w, h): """"For GUI backends, resize the window (in pixels)."""
[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)