UT3Tangent.stack_tangents
=========================

.. py:method:: t3toolbox.uniform_manifold.UT3Tangent.stack_tangents(tree)
   :staticmethod:


   .. code-block:: python

      def stack_tangents(tree) -> 'UT3Tangent':


   Stack a ``K``-shaped tree of tangents (sharing one frame) into a tangent-stacked UT3Tangent.

   Inverse of :py:meth:`unstack_tangents`. Requires every leaf to be at the **same frame** (the
   numerical same-frame check, as in :py:meth:`__add__`): the tangents being stacked must live in the
   same tangent space. The first leaf's frame is reused; the variations stack over the new outer
   tangent stack ``K``.