class_docstr: Camera implementing 2D pan/zoom mouse interaction.
  
  For this camera, the ``scale_factor`` indicates the zoom level, and
  the ``center`` indicates the center position of the view.
  
  By default, this camera inverts the y axis of the scene. This usually
  results in the scene +y axis pointing upward because widgets (including
  ViewBox) have their +y axis pointing downward.
  
  Parameters
  ----------
  rect : Rect
      A Rect object or 4-element tuple that specifies the rectangular
      area to show.
  aspect : float | None
      The aspect ratio (i.e. scaling) between x and y dimension of
      the scene. E.g. to show a square image as square, the aspect
      should be 1. If None (default) the x and y dimensions are scaled
      independently.
  **kwargs : dict
      Keyword arguments to pass to `BaseCamera`.
  
  Notes
  -----
  Interaction:
  
      * LMB: pan the view
      * RMB or scroll: zooms the view
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docstr: The rectangular border of the ViewBox visible area.
  
  This is expressed in the coordinate system of the scene.
  See :class:`~vispy.geometry.rect.Rect` for different ways this can
  be specified.
  
  Note that the rectangle can have negative width or height, in
  which case the corresponding dimension is flipped (this flipping
  is independent from the camera's ``flip`` property).
docstr_tok: ["The","rectangular","border","of","the","ViewBox","visible","area",".","This","is","expressed","in","the","coordinate","system","of","the","scene",".","See",":","class",":","`","~vispy.geometry.rect.Rect","`","for","different","ways","this","can","be","specified",".","Note","that","the","rectangle","can","have","negative","width","or","height",",","in","which","case","the","corresponding","dimension","is","flipped","(","this","flipping","is","independent","from","the","camera","'s","``","flip","``","property",")","."]
code: def rect(self):
      """The rectangular border of the ViewBox visible area.
  
      This is expressed in the coordinate system of the scene.
      See :class:`~vispy.geometry.rect.Rect` for different ways this can
      be specified.
  
      Note that the rectangle can have negative width or height, in
      which case the corresponding dimension is flipped (this flipping
      is independent from the camera's ``flip`` property).
      """
      return self._rect
  
imports: from __future__ import division
  import numpy
  from .base_camera import BaseCamera
  from ...geometry import Rect
  from ...visuals.transforms import STTransform, MatrixTransform
label_desc: Use image node_id 6 for calling the PanZoomCamera obj's underlying member method code with example usage: obj.rect() and returns: self