;| Flipping a Block about X or Y axis                                         |
|    Prepared By: M. Sahin Guvercin (ProhibiT)                               |
|                    14.02.2024 cizimokulu.com                               |;
(defun c:fLbL (/ NsN BsP oOm AnG OmD fLL)
  (while (not NsN) (princ "\nSelect Block...")
    (setq NsN (vlax-ename->vla-object
                (ssname (ssget "+.:s" (list (cons 0 "INSERT"))) 0))))
  (setq BsP (vlax-get NsN 'InsertionPoint)
        oOm (getvar "orthomode") OmD (setvar "orthomode" 1)
        AnG (getorient BsP) OmD (setvar "orthomode" oOm))
  (if (or (= AnG 0.0) (= AnG pi)) (setq fLL T))
  (vla-transformby Nsn
    (vlax-tmatrix (list (list 1 0 0 (-(car BsP))) (list 0 1 0 (-(cadr BsP)))
                        (list 0 0 1 (-(caddr BsP))) (list 0 0 0 1))))
  (if fLL
    (vla-transformby NsN (vlax-tmatrix (list (list 1 0 0 0) (list 0 -1 0 0)
                           (list 0 0 1 0) (list 0 0 0 1))))
    (vla-transformby NsN (vlax-tmatrix (list (list -1 0 0 0) (list 0 1 0 0)
                           (list 0 0 1 0) (list 0 0 0 1)))))
  (vla-transformby Nsn (vlax-tmatrix (list (list 1 0 0 (car BsP))
                         (list 0 1 0 (cadr BsP)) (list 0 0 1 (caddr BsP))
                           (list 0 0 0 1)))) (princ))