def to_(self, data_pts):
        """Reverse of :meth:`from_`."""
        data_pts = np.asarray(data_pts, dtype=np.float)
        has_z = (data_pts.shape[-1] > 2)

        if self.use_center:
            data_pts = data_pts - self.viewer.data_off

        # subtract data indexes at center reference pixel
        ref_pt = [self.viewer._org_x, self.viewer._org_y]
        if has_z:
            ref_pt.append(self.viewer._org_z)

        off_pts = np.subtract(data_pts, ref_pt)
        return off_pts
Reverse of :meth:`from_`.