code: def rel_curve_to(self, dx1, dy1, dx2, dy2, dx3, dy3):
          
          cairo.cairo_rel_curve_to(self._pointer, dx1, dy1, dx2, dy2, dx3, dy3)
          self._check_status()
docs: Relative-coordinate version of :meth:`curve_to`.
          All offsets are relative to the current point.
          Adds a cubic Bézier spline to the path from the current point
          to a point offset from the current point by ``(dx3, dy3)``,
          using points offset by ``(dx1, dy1)`` and ``(dx2, dy2)``
          as the control points.
          After this call the current point will be offset by ``(dx3, dy3)``.
  
          Given a current point of ``(x, y)``,
          ``context.rel_curve_to(dx1, dy1, dx2, dy2, dx3, dy3)``
          is logically equivalent to
          ``context.curve_to(x+dx1, y+dy1, x+dx2, y+dy2, x+dx3, y+dy3)``.
  
          :param dx1: The X offset to the first control point.
          :param dy1: The Y offset to the first control point.
          :param dx2: The X offset to the second control point.
          :param dy2: The Y offset to the second control point.
          :param dx3: The X offset to the end of the curve.
          :param dy3: The Y offset to the end of the curve.
          :type dx1: float
          :type dy1: float
          :type dx2: float
          :type dy2: float
          :type dx3: float
          :type dy3: float
          :raises:
              :exc:`CairoError` if there is no current point.
              Doing so will cause leave the context in an error state.