Class TransformListener

source code

 object --+        
          |        
Transformer --+    
              |    
 TransformerROS --+
                  |
                 TransformListener

TransformListener is a subclass of :class:`tf.TransformerROS` that
subscribes to the ``"/tf"`` message topic, and calls :meth:`tf.Transformer.setTransform`
with each incoming transformation message.

In this way a TransformListener object automatically
stays up to to date with all current transforms.  Typical usage might be::

    import tf
    from geometry_msgs.msg import PointStamped

    class MyNode:

        def __init__(self):

            self.tl = tf.TransformListener()
            rospy.Subscriber("/sometopic", PointStamped, self.some_message_handler)
            ...
        
        def some_message_handler(self, point_stamped):

            # want to work on the point in the "world" frame
            point_in_world = self.tl.transformPoint("world", point_stamped)
            ...