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transforms.py
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2865 lines (2350 loc) · 96.2 KB
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"""
matplotlib includes a framework for arbitrary geometric
transformations that is used determine the final position of all
elements drawn on the canvas.
Transforms are composed into trees of :class:`TransformNode` objects
whose actual value depends on their children. When the contents of
children change, their parents are automatically invalidated. The
next time an invalidated transform is accessed, it is recomputed to
reflect those changes. This invalidation/caching approach prevents
unnecessary recomputations of transforms, and contributes to better
interactive performance.
For example, here is a graph of the transform tree used to plot data
to the graph:
.. image:: ../_static/transforms.png
The framework can be used for both affine and non-affine
transformations. However, for speed, we want use the backend
renderers to perform affine transformations whenever possible.
Therefore, it is possible to perform just the affine or non-affine
part of a transformation on a set of data. The affine is always
assumed to occur after the non-affine. For any transform::
full transform == non-affine part + affine part
The backends are not expected to handle non-affine transformations
themselves.
"""
from __future__ import (absolute_import, division, print_function,
unicode_literals)
import six
import numpy as np
from matplotlib._path import (affine_transform, count_bboxes_overlapping_bbox,
update_path_extents)
from numpy.linalg import inv
import weakref
import warnings
from .path import Path
DEBUG = False
class TransformNode(object):
"""
:class:`TransformNode` is the base class for anything that
participates in the transform tree and needs to invalidate its
parents or be invalidated. This includes classes that are not
really transforms, such as bounding boxes, since some transforms
depend on bounding boxes to compute their values.
"""
_gid = 0
# Invalidation may affect only the affine part. If the
# invalidation was "affine-only", the _invalid member is set to
# INVALID_AFFINE_ONLY
INVALID_NON_AFFINE = 1
INVALID_AFFINE = 2
INVALID = INVALID_NON_AFFINE | INVALID_AFFINE
# Some metadata about the transform, used to determine whether an
# invalidation is affine-only
is_affine = False
is_bbox = False
pass_through = False
"""
If pass_through is True, all ancestors will always be
invalidated, even if 'self' is already invalid.
"""
def __init__(self, shorthand_name=None):
"""
Creates a new :class:`TransformNode`.
**shorthand_name** - a string representing the "name" of this
transform. The name carries no significance
other than to improve the readability of
``str(transform)`` when DEBUG=True.
"""
self._parents = {}
# TransformNodes start out as invalid until their values are
# computed for the first time.
self._invalid = 1
self._shorthand_name = shorthand_name or ''
if DEBUG:
def __str__(self):
# either just return the name of this TransformNode, or it's repr
return self._shorthand_name or repr(self)
def __getstate__(self):
d = self.__dict__.copy()
# turn the dictionary with weak values into a normal dictionary
d['_parents'] = dict((k, v()) for (k, v) in
six.iteritems(self._parents))
return d
def __setstate__(self, data_dict):
self.__dict__ = data_dict
# turn the normal dictionary back into a dictionary with weak
# values
self._parents = dict((k, weakref.ref(v)) for (k, v) in
six.iteritems(self._parents) if v is not None)
def __copy__(self, *args):
raise NotImplementedError(
"TransformNode instances can not be copied. " +
"Consider using frozen() instead.")
__deepcopy__ = __copy__
def invalidate(self):
"""
Invalidate this :class:`TransformNode` and triggers an
invalidation of its ancestors. Should be called any
time the transform changes.
"""
value = self.INVALID
if self.is_affine:
value = self.INVALID_AFFINE
return self._invalidate_internal(value, invalidating_node=self)
def _invalidate_internal(self, value, invalidating_node):
"""
Called by :meth:`invalidate` and subsequently ascends the transform
stack calling each TransformNode's _invalidate_internal method.
"""
# determine if this call will be an extension to the invalidation
# status. If not, then a shortcut means that we needn't invoke an
# invalidation up the transform stack as it will already have been
# invalidated.
# N.B This makes the invalidation sticky, once a transform has been
# invalidated as NON_AFFINE, then it will always be invalidated as
# NON_AFFINE even when triggered with a AFFINE_ONLY invalidation.
# In most cases this is not a problem (i.e. for interactive panning and
# zooming) and the only side effect will be on performance.
status_changed = self._invalid < value
if self.pass_through or status_changed:
self._invalid = value
for parent in list(six.itervalues(self._parents)):
# Dereference the weak reference
parent = parent()
if parent is not None:
parent._invalidate_internal(
value=value, invalidating_node=self)
def set_children(self, *children):
"""
Set the children of the transform, to let the invalidation
system know which transforms can invalidate this transform.
Should be called from the constructor of any transforms that
depend on other transforms.
"""
# Parents are stored as weak references, so that if the
# parents are destroyed, references from the children won't
# keep them alive.
for child in children:
child._parents[id(self)] = weakref.ref(self)
if DEBUG:
_set_children = set_children
def set_children(self, *children):
self._set_children(*children)
self._children = children
set_children.__doc__ = _set_children.__doc__
def frozen(self):
"""
Returns a frozen copy of this transform node. The frozen copy
will not update when its children change. Useful for storing
a previously known state of a transform where
``copy.deepcopy()`` might normally be used.
"""
return self
if DEBUG:
def write_graphviz(self, fobj, highlight=[]):
"""
For debugging purposes.
Writes the transform tree rooted at 'self' to a graphviz "dot"
format file. This file can be run through the "dot" utility
to produce a graph of the transform tree.
Affine transforms are marked in blue. Bounding boxes are
marked in yellow.
*fobj*: A Python file-like object
Once the "dot" file has been created, it can be turned into a
png easily with::
$> dot -Tpng -o $OUTPUT_FILE $DOT_FILE
"""
seen = set()
def recurse(root):
if root in seen:
return
seen.add(root)
props = {}
label = root.__class__.__name__
if root._invalid:
label = '[%s]' % label
if root in highlight:
props['style'] = 'bold'
props['shape'] = 'box'
props['label'] = '"%s"' % label
props = ' '.join(['%s=%s' % (key, val)
for key, val
in six.iteritems(props)])
fobj.write('%s [%s];\n' %
(hash(root), props))
if hasattr(root, '_children'):
for child in root._children:
name = '?'
for key, val in six.iteritems(root.__dict__):
if val is child:
name = key
break
fobj.write('"%s" -> "%s" [label="%s", fontsize=10];\n'
% (hash(root),
hash(child),
name))
recurse(child)
fobj.write("digraph G {\n")
recurse(self)
fobj.write("}\n")
class BboxBase(TransformNode):
"""
This is the base class of all bounding boxes, and provides
read-only access to its data. A mutable bounding box is provided
by the :class:`Bbox` class.
The canonical representation is as two points, with no
restrictions on their ordering. Convenience properties are
provided to get the left, bottom, right and top edges and width
and height, but these are not stored explicitly.
"""
is_bbox = True
is_affine = True
#* Redundant: Removed for performance
#
# def __init__(self):
# TransformNode.__init__(self)
if DEBUG:
def _check(points):
if isinstance(points, np.ma.MaskedArray):
warnings.warn("Bbox bounds are a masked array.")
points = np.asarray(points)
if (points[1, 0] - points[0, 0] == 0 or
points[1, 1] - points[0, 1] == 0):
warnings.warn("Singular Bbox.")
_check = staticmethod(_check)
def frozen(self):
return Bbox(self.get_points().copy())
frozen.__doc__ = TransformNode.__doc__
def __array__(self, *args, **kwargs):
return self.get_points()
def is_unit(self):
"""
Returns True if the :class:`Bbox` is the unit bounding box
from (0, 0) to (1, 1).
"""
return list(self.get_points().flatten()) == [0., 0., 1., 1.]
def _get_x0(self):
return self.get_points()[0, 0]
x0 = property(_get_x0, None, None, """
(property) :attr:`x0` is the first of the pair of *x* coordinates that
define the bounding box. :attr:`x0` is not guaranteed to be
less than :attr:`x1`. If you require that, use :attr:`xmin`.""")
def _get_y0(self):
return self.get_points()[0, 1]
y0 = property(_get_y0, None, None, """
(property) :attr:`y0` is the first of the pair of *y* coordinates that
define the bounding box. :attr:`y0` is not guaranteed to be
less than :attr:`y1`. If you require that, use :attr:`ymin`.""")
def _get_x1(self):
return self.get_points()[1, 0]
x1 = property(_get_x1, None, None, """
(property) :attr:`x1` is the second of the pair of *x* coordinates
that define the bounding box. :attr:`x1` is not guaranteed to be
greater than :attr:`x0`. If you require that, use :attr:`xmax`.""")
def _get_y1(self):
return self.get_points()[1, 1]
y1 = property(_get_y1, None, None, """
(property) :attr:`y1` is the second of the pair of *y* coordinates
that define the bounding box. :attr:`y1` is not guaranteed to be
greater than :attr:`y0`. If you require that, use :attr:`ymax`.""")
def _get_p0(self):
return self.get_points()[0]
p0 = property(_get_p0, None, None, """
(property) :attr:`p0` is the first pair of (*x*, *y*) coordinates
that define the bounding box. It is not guaranteed to be the
bottom-left corner. For that, use :attr:`min`.""")
def _get_p1(self):
return self.get_points()[1]
p1 = property(_get_p1, None, None, """
(property) :attr:`p1` is the second pair of (*x*, *y*) coordinates
that define the bounding box. It is not guaranteed to be the
top-right corner. For that, use :attr:`max`.""")
def _get_xmin(self):
return min(self.get_points()[:, 0])
xmin = property(_get_xmin, None, None, """
(property) :attr:`xmin` is the left edge of the bounding box.""")
def _get_ymin(self):
return min(self.get_points()[:, 1])
ymin = property(_get_ymin, None, None, """
(property) :attr:`ymin` is the bottom edge of the bounding box.""")
def _get_xmax(self):
return max(self.get_points()[:, 0])
xmax = property(_get_xmax, None, None, """
(property) :attr:`xmax` is the right edge of the bounding box.""")
def _get_ymax(self):
return max(self.get_points()[:, 1])
ymax = property(_get_ymax, None, None, """
(property) :attr:`ymax` is the top edge of the bounding box.""")
def _get_min(self):
return [min(self.get_points()[:, 0]),
min(self.get_points()[:, 1])]
min = property(_get_min, None, None, """
(property) :attr:`min` is the bottom-left corner of the bounding
box.""")
def _get_max(self):
return [max(self.get_points()[:, 0]),
max(self.get_points()[:, 1])]
max = property(_get_max, None, None, """
(property) :attr:`max` is the top-right corner of the bounding box.""")
def _get_intervalx(self):
return self.get_points()[:, 0]
intervalx = property(_get_intervalx, None, None, """
(property) :attr:`intervalx` is the pair of *x* coordinates that define
the bounding box. It is not guaranteed to be sorted from left to
right.""")
def _get_intervaly(self):
return self.get_points()[:, 1]
intervaly = property(_get_intervaly, None, None, """
(property) :attr:`intervaly` is the pair of *y* coordinates that define
the bounding box. It is not guaranteed to be sorted from bottom to
top.""")
def _get_width(self):
points = self.get_points()
return points[1, 0] - points[0, 0]
width = property(_get_width, None, None, """
(property) The width of the bounding box. It may be negative if
:attr:`x1` < :attr:`x0`.""")
def _get_height(self):
points = self.get_points()
return points[1, 1] - points[0, 1]
height = property(_get_height, None, None, """
(property) The height of the bounding box. It may be negative if
:attr:`y1` < :attr:`y0`.""")
def _get_size(self):
points = self.get_points()
return points[1] - points[0]
size = property(_get_size, None, None, """
(property) The width and height of the bounding box. May be negative,
in the same way as :attr:`width` and :attr:`height`.""")
def _get_bounds(self):
x0, y0, x1, y1 = self.get_points().flatten()
return (x0, y0, x1 - x0, y1 - y0)
bounds = property(_get_bounds, None, None, """
(property) Returns (:attr:`x0`, :attr:`y0`, :attr:`width`,
:attr:`height`).""")
def _get_extents(self):
return self.get_points().flatten().copy()
extents = property(_get_extents, None, None, """
(property) Returns (:attr:`x0`, :attr:`y0`, :attr:`x1`,
:attr:`y1`).""")
def get_points(self):
return NotImplementedError()
def containsx(self, x):
"""
Returns True if *x* is between or equal to :attr:`x0` and
:attr:`x1`.
"""
x0, x1 = self.intervalx
return ((x0 < x1
and (x >= x0 and x <= x1))
or (x >= x1 and x <= x0))
def containsy(self, y):
"""
Returns True if *y* is between or equal to :attr:`y0` and
:attr:`y1`.
"""
y0, y1 = self.intervaly
return ((y0 < y1
and (y >= y0 and y <= y1))
or (y >= y1 and y <= y0))
def contains(self, x, y):
"""
Returns *True* if (*x*, *y*) is a coordinate inside the
bounding box or on its edge.
"""
return self.containsx(x) and self.containsy(y)
def overlaps(self, other):
"""
Returns True if this bounding box overlaps with the given
bounding box *other*.
"""
ax1, ay1, ax2, ay2 = self._get_extents()
bx1, by1, bx2, by2 = other._get_extents()
if any(np.isnan(v) for v in [ax1, ay1, ax2, ay2, bx1, by1, bx2, by2]):
return False
if ax2 < ax1:
ax2, ax1 = ax1, ax2
if ay2 < ay1:
ay2, ay1 = ay1, ay2
if bx2 < bx1:
bx2, bx1 = bx1, bx2
if by2 < by1:
by2, by1 = by1, by2
return not ((bx2 < ax1) or
(by2 < ay1) or
(bx1 > ax2) or
(by1 > ay2))
def fully_containsx(self, x):
"""
Returns True if *x* is between but not equal to :attr:`x0` and
:attr:`x1`.
"""
x0, x1 = self.intervalx
return ((x0 < x1
and (x > x0 and x < x1))
or (x > x1 and x < x0))
def fully_containsy(self, y):
"""
Returns True if *y* is between but not equal to :attr:`y0` and
:attr:`y1`.
"""
y0, y1 = self.intervaly
return ((y0 < y1
and (y > y0 and y < y1))
or (y > y1 and y < y0))
def fully_contains(self, x, y):
"""
Returns True if (*x*, *y*) is a coordinate inside the bounding
box, but not on its edge.
"""
return self.fully_containsx(x) \
and self.fully_containsy(y)
def fully_overlaps(self, other):
"""
Returns True if this bounding box overlaps with the given
bounding box *other*, but not on its edge alone.
"""
ax1, ay1, ax2, ay2 = self._get_extents()
bx1, by1, bx2, by2 = other._get_extents()
if ax2 < ax1:
ax2, ax1 = ax1, ax2
if ay2 < ay1:
ay2, ay1 = ay1, ay2
if bx2 < bx1:
bx2, bx1 = bx1, bx2
if by2 < by1:
by2, by1 = by1, by2
return not ((bx2 <= ax1) or
(by2 <= ay1) or
(bx1 >= ax2) or
(by1 >= ay2))
def transformed(self, transform):
"""
Return a new :class:`Bbox` object, statically transformed by
the given transform.
"""
pts = self.get_points()
ll, ul, lr = transform.transform(np.array([pts[0],
[pts[0, 0], pts[1, 1]], [pts[1, 0], pts[0, 1]]]))
return Bbox([ll, [lr[0], ul[1]]])
def inverse_transformed(self, transform):
"""
Return a new :class:`Bbox` object, statically transformed by
the inverse of the given transform.
"""
return self.transformed(transform.inverted())
coefs = {'C': (0.5, 0.5),
'SW': (0, 0),
'S': (0.5, 0),
'SE': (1.0, 0),
'E': (1.0, 0.5),
'NE': (1.0, 1.0),
'N': (0.5, 1.0),
'NW': (0, 1.0),
'W': (0, 0.5)}
def anchored(self, c, container=None):
"""
Return a copy of the :class:`Bbox`, shifted to position *c*
within a container.
*c*: may be either:
* a sequence (*cx*, *cy*) where *cx* and *cy* range from 0
to 1, where 0 is left or bottom and 1 is right or top
* a string:
- 'C' for centered
- 'S' for bottom-center
- 'SE' for bottom-left
- 'E' for left
- etc.
Optional argument *container* is the box within which the
:class:`Bbox` is positioned; it defaults to the initial
:class:`Bbox`.
"""
if container is None:
container = self
l, b, w, h = container.bounds
if isinstance(c, six.string_types):
cx, cy = self.coefs[c]
else:
cx, cy = c
L, B, W, H = self.bounds
return Bbox(self._points +
[(l + cx * (w - W)) - L,
(b + cy * (h - H)) - B])
def shrunk(self, mx, my):
"""
Return a copy of the :class:`Bbox`, shrunk by the factor *mx*
in the *x* direction and the factor *my* in the *y* direction.
The lower left corner of the box remains unchanged. Normally
*mx* and *my* will be less than 1, but this is not enforced.
"""
w, h = self.size
return Bbox([self._points[0],
self._points[0] + [mx * w, my * h]])
def shrunk_to_aspect(self, box_aspect, container=None, fig_aspect=1.0):
"""
Return a copy of the :class:`Bbox`, shrunk so that it is as
large as it can be while having the desired aspect ratio,
*box_aspect*. If the box coordinates are relative---that
is, fractions of a larger box such as a figure---then the
physical aspect ratio of that figure is specified with
*fig_aspect*, so that *box_aspect* can also be given as a
ratio of the absolute dimensions, not the relative dimensions.
"""
if box_aspect <= 0 or fig_aspect <= 0:
raise ValueError("'box_aspect' and 'fig_aspect' must be positive")
if container is None:
container = self
w, h = container.size
H = w * box_aspect / fig_aspect
if H <= h:
W = w
else:
W = h * fig_aspect / box_aspect
H = h
return Bbox([self._points[0],
self._points[0] + (W, H)])
def splitx(self, *args):
"""
e.g., ``bbox.splitx(f1, f2, ...)``
Returns a list of new :class:`Bbox` objects formed by
splitting the original one with vertical lines at fractional
positions *f1*, *f2*, ...
"""
boxes = []
xf = [0] + list(args) + [1]
x0, y0, x1, y1 = self._get_extents()
w = x1 - x0
for xf0, xf1 in zip(xf[:-1], xf[1:]):
boxes.append(Bbox([[x0 + xf0 * w, y0], [x0 + xf1 * w, y1]]))
return boxes
def splity(self, *args):
"""
e.g., ``bbox.splitx(f1, f2, ...)``
Returns a list of new :class:`Bbox` objects formed by
splitting the original one with horizontal lines at fractional
positions *f1*, *f2*, ...
"""
boxes = []
yf = [0] + list(args) + [1]
x0, y0, x1, y1 = self._get_extents()
h = y1 - y0
for yf0, yf1 in zip(yf[:-1], yf[1:]):
boxes.append(Bbox([[x0, y0 + yf0 * h], [x1, y0 + yf1 * h]]))
return boxes
def count_contains(self, vertices):
"""
Count the number of vertices contained in the :class:`Bbox`.
*vertices* is a Nx2 Numpy array.
"""
if len(vertices) == 0:
return 0
vertices = np.asarray(vertices)
x0, y0, x1, y1 = self._get_extents()
with np.errstate(invalid='ignore'):
dx0 = np.sign(vertices[:, 0] - x0)
dy0 = np.sign(vertices[:, 1] - y0)
dx1 = np.sign(vertices[:, 0] - x1)
dy1 = np.sign(vertices[:, 1] - y1)
inside = ((abs(dx0 + dx1) + abs(dy0 + dy1)) == 0)
return np.sum(inside)
def count_overlaps(self, bboxes):
"""
Count the number of bounding boxes that overlap this one.
bboxes is a sequence of :class:`BboxBase` objects
"""
return count_bboxes_overlapping_bbox(
self, np.atleast_3d([np.array(x) for x in bboxes]))
def expanded(self, sw, sh):
"""
Return a new :class:`Bbox` which is this :class:`Bbox`
expanded around its center by the given factors *sw* and
*sh*.
"""
width = self.width
height = self.height
deltaw = (sw * width - width) / 2.0
deltah = (sh * height - height) / 2.0
a = np.array([[-deltaw, -deltah], [deltaw, deltah]])
return Bbox(self._points + a)
def padded(self, p):
"""
Return a new :class:`Bbox` that is padded on all four sides by
the given value.
"""
points = self.get_points()
return Bbox(points + [[-p, -p], [p, p]])
def translated(self, tx, ty):
"""
Return a copy of the :class:`Bbox`, statically translated by
*tx* and *ty*.
"""
return Bbox(self._points + (tx, ty))
def corners(self):
"""
Return an array of points which are the four corners of this
rectangle. For example, if this :class:`Bbox` is defined by
the points (*a*, *b*) and (*c*, *d*), :meth:`corners` returns
(*a*, *b*), (*a*, *d*), (*c*, *b*) and (*c*, *d*).
"""
l, b, r, t = self.get_points().flatten()
return np.array([[l, b], [l, t], [r, b], [r, t]])
def rotated(self, radians):
"""
Return a new bounding box that bounds a rotated version of
this bounding box by the given radians. The new bounding box
is still aligned with the axes, of course.
"""
corners = self.corners()
corners_rotated = Affine2D().rotate(radians).transform(corners)
bbox = Bbox.unit()
bbox.update_from_data_xy(corners_rotated, ignore=True)
return bbox
@staticmethod
def union(bboxes):
"""
Return a :class:`Bbox` that contains all of the given bboxes.
"""
if not len(bboxes):
raise ValueError("'bboxes' cannot be empty")
if len(bboxes) == 1:
return bboxes[0]
x0 = np.inf
y0 = np.inf
x1 = -np.inf
y1 = -np.inf
for bbox in bboxes:
points = bbox.get_points()
xs = points[:, 0]
ys = points[:, 1]
x0 = min(x0, np.min(xs))
y0 = min(y0, np.min(ys))
x1 = max(x1, np.max(xs))
y1 = max(y1, np.max(ys))
return Bbox.from_extents(x0, y0, x1, y1)
@staticmethod
def intersection(bbox1, bbox2):
"""
Return the intersection of the two bboxes or None
if they do not intersect.
Implements the algorithm described at:
http://www.tekpool.com/node/2687
"""
intersects = not (bbox2.xmin > bbox1.xmax or
bbox2.xmax < bbox1.xmin or
bbox2.ymin > bbox1.ymax or
bbox2.ymax < bbox1.ymin)
if intersects:
x0 = max([bbox1.xmin, bbox2.xmin])
x1 = min([bbox1.xmax, bbox2.xmax])
y0 = max([bbox1.ymin, bbox2.ymin])
y1 = min([bbox1.ymax, bbox2.ymax])
return Bbox.from_extents(x0, y0, x1, y1)
return None
class Bbox(BboxBase):
"""
A mutable bounding box.
"""
def __init__(self, points, **kwargs):
"""
*points*: a 2x2 numpy array of the form [[x0, y0], [x1, y1]]
If you need to create a :class:`Bbox` object from another form
of data, consider the static methods :meth:`unit`,
:meth:`from_bounds` and :meth:`from_extents`.
"""
BboxBase.__init__(self, **kwargs)
points = np.asarray(points, float)
if points.shape != (2, 2):
raise ValueError('Bbox points must be of the form '
'"[[x0, y0], [x1, y1]]".')
self._points = points
self._minpos = np.array([0.0000001, 0.0000001])
self._ignore = True
# it is helpful in some contexts to know if the bbox is a
# default or has been mutated; we store the orig points to
# support the mutated methods
self._points_orig = self._points.copy()
if DEBUG:
___init__ = __init__
def __init__(self, points, **kwargs):
self._check(points)
self.___init__(points, **kwargs)
def invalidate(self):
self._check(self._points)
TransformNode.invalidate(self)
@staticmethod
def unit():
"""
(staticmethod) Create a new unit :class:`Bbox` from (0, 0) to
(1, 1).
"""
return Bbox(np.array([[0.0, 0.0], [1.0, 1.0]], float))
@staticmethod
def null():
"""
(staticmethod) Create a new null :class:`Bbox` from (inf, inf) to
(-inf, -inf).
"""
return Bbox(np.array([[np.inf, np.inf], [-np.inf, -np.inf]], float))
@staticmethod
def from_bounds(x0, y0, width, height):
"""
(staticmethod) Create a new :class:`Bbox` from *x0*, *y0*,
*width* and *height*.
*width* and *height* may be negative.
"""
return Bbox.from_extents(x0, y0, x0 + width, y0 + height)
@staticmethod
def from_extents(*args):
"""
(staticmethod) Create a new Bbox from *left*, *bottom*,
*right* and *top*.
The *y*-axis increases upwards.
"""
points = np.array(args, dtype=float).reshape(2, 2)
return Bbox(points)
def __format__(self, fmt):
return (
'Bbox(x0={0.x0:{1}}, y0={0.y0:{1}}, x1={0.x1:{1}}, y1={0.y1:{1}})'.
format(self, fmt))
def __str__(self):
return format(self, '')
def __repr__(self):
return 'Bbox([[{0.x0}, {0.y0}], [{0.x1}, {0.y1}]])'.format(self)
def ignore(self, value):
"""
Set whether the existing bounds of the box should be ignored
by subsequent calls to :meth:`update_from_data` or
:meth:`update_from_data_xy`.
*value*:
- When True, subsequent calls to :meth:`update_from_data`
will ignore the existing bounds of the :class:`Bbox`.
- When False, subsequent calls to :meth:`update_from_data`
will include the existing bounds of the :class:`Bbox`.
"""
self._ignore = value
def update_from_data(self, x, y, ignore=None):
"""
Update the bounds of the :class:`Bbox` based on the passed in
data. After updating, the bounds will have positive *width*
and *height*; *x0* and *y0* will be the minimal values.
*x*: a numpy array of *x*-values
*y*: a numpy array of *y*-values
*ignore*:
- when True, ignore the existing bounds of the :class:`Bbox`.
- when False, include the existing bounds of the :class:`Bbox`.
- when None, use the last value passed to :meth:`ignore`.
"""
warnings.warn(
"update_from_data requires a memory copy -- please replace with "
"update_from_data_xy")
xy = np.hstack((x.reshape((len(x), 1)), y.reshape((len(y), 1))))
return self.update_from_data_xy(xy, ignore)
def update_from_path(self, path, ignore=None, updatex=True, updatey=True):
"""
Update the bounds of the :class:`Bbox` based on the passed in
data. After updating, the bounds will have positive *width*
and *height*; *x0* and *y0* will be the minimal values.
*path*: a :class:`~matplotlib.path.Path` instance
*ignore*:
- when True, ignore the existing bounds of the :class:`Bbox`.
- when False, include the existing bounds of the :class:`Bbox`.
- when None, use the last value passed to :meth:`ignore`.
*updatex*: when True, update the x values
*updatey*: when True, update the y values
"""
if ignore is None:
ignore = self._ignore
if path.vertices.size == 0:
return
points, minpos, changed = update_path_extents(
path, None, self._points, self._minpos, ignore)
if changed:
self.invalidate()
if updatex:
self._points[:, 0] = points[:, 0]
self._minpos[0] = minpos[0]
if updatey:
self._points[:, 1] = points[:, 1]
self._minpos[1] = minpos[1]
def update_from_data_xy(self, xy, ignore=None, updatex=True, updatey=True):
"""
Update the bounds of the :class:`Bbox` based on the passed in
data. After updating, the bounds will have positive *width*
and *height*; *x0* and *y0* will be the minimal values.
*xy*: a numpy array of 2D points
*ignore*:
- when True, ignore the existing bounds of the :class:`Bbox`.
- when False, include the existing bounds of the :class:`Bbox`.
- when None, use the last value passed to :meth:`ignore`.
*updatex*: when True, update the x values
*updatey*: when True, update the y values
"""
if len(xy) == 0:
return
path = Path(xy)
self.update_from_path(path, ignore=ignore,
updatex=updatex, updatey=updatey)
def _set_x0(self, val):
self._points[0, 0] = val
self.invalidate()
x0 = property(BboxBase._get_x0, _set_x0)
def _set_y0(self, val):
self._points[0, 1] = val
self.invalidate()
y0 = property(BboxBase._get_y0, _set_y0)
def _set_x1(self, val):
self._points[1, 0] = val
self.invalidate()
x1 = property(BboxBase._get_x1, _set_x1)
def _set_y1(self, val):
self._points[1, 1] = val
self.invalidate()
y1 = property(BboxBase._get_y1, _set_y1)
def _set_p0(self, val):
self._points[0] = val
self.invalidate()
p0 = property(BboxBase._get_p0, _set_p0)
def _set_p1(self, val):
self._points[1] = val
self.invalidate()
p1 = property(BboxBase._get_p1, _set_p1)
def _set_intervalx(self, interval):
self._points[:, 0] = interval
self.invalidate()
intervalx = property(BboxBase._get_intervalx, _set_intervalx)
def _set_intervaly(self, interval):
self._points[:, 1] = interval
self.invalidate()
intervaly = property(BboxBase._get_intervaly, _set_intervaly)
def _set_bounds(self, bounds):
l, b, w, h = bounds
points = np.array([[l, b], [l + w, b + h]], float)
if np.any(self._points != points):
self._points = points
self.invalidate()