parameters: (self, point)
docstring: Update current cursor window coordinates.
docstring_summary: Update current cursor window coordinates.
docstring_tokens: Update current cursor window coordinates .
function: def drag(self, point):
          """Update current cursor window coordinates."""
          vnow = arcball_map_to_sphere(point, self._center, self._radius)
          if self._axis is not None:
              vnow = arcball_constrain_to_axis(vnow, self._axis)
          self._qpre = self._qnow
          t = numpy.cross(self._vdown, vnow)
          if numpy.dot(t, t) < _EPS:
              self._qnow = self._qdown
          else:
              q = [numpy.dot(self._vdown, vnow), t[0], t[1], t[2]]
              self._qnow = quaternion_multiply(q, self._qdown)
function_tokens: def drag ( self , point ) : vnow = arcball_map_to_sphere ( point , self . _center , self . _radius ) if self . _axis is not None : vnow = arcball_constrain_to_axis ( vnow , self . _axis ) self . _qpre = self . _qnow t = numpy . cross ( self . _vdown , vnow ) if numpy . dot ( t , t ) < _EPS : self . _qnow = self . _qdown else : q = [ numpy . dot ( self . _vdown , vnow ) , t [ 0 ] , t [ 1 ] , t [ 2 ] ] self . _qnow = quaternion_multiply ( q , self . _qdown )