Class LockableBbox

lib/matplotlib/transforms.py:1207–1325

A `Bbox` where some elements may be locked at certain values. When the child bounding box changes, the bounds of this bbox will update accordingly with the exception of the locked elements.

class LockableBbox(BboxBase):
    """
    A `Bbox` where some elements may be locked at certain values.

    When the child bounding box changes, the bounds of this bbox will update
    accordingly with the exception of the locked elements.
    """
    def __init__(self, bbox, x0=None, y0=None, x1=None, y1=None, **kwargs):
        """
        Parameters
        ----------
        bbox : `Bbox`
            The child bounding box to wrap.

        x0 : float or None
            The locked value for x0, or None to leave unlocked.

        y0 : float or None
            The locked value for y0, or None to leave unlocked.

        x1 : float or None
            The locked value for x1, or None to leave unlocked.

        y1 : float or None
            The locked value for y1, or None to leave unlocked.

        """
        _api.check_isinstance(BboxBase, bbox=bbox)
        super().__init__(**kwargs)
        self._bbox = bbox
        self.set_children(bbox)
        self._points = None
        fp = [x0, y0, x1, y1]
        mask = [val is None for val in fp]
        self._locked_points = np.ma.array(fp, float, mask=mask).reshape((2, 2))

    __str__ = _make_str_method("_bbox", "_locked_points")

    def get_points(self):
        # docstring inherited
        if self._invalid:
            points = self._bbox.get_points()
            self._points = np.where(self._locked_points.mask,
                                    points,
                                    self._locked_points)
            self._invalid = 0
        return self._points

    if DEBUG:
        _get_points = get_points

        def get_points(self):
            points = self._get_points()
            self._check(points)
            return points

    @property
    def locked_x0(self):