;;;Set X-hairs and optionally viewtwist.
;;;
;;;
;;;
;;;
(DEFUN rotx_error (msg /)
  (PRINC (STRCAT "\nError: " msg))
  (SETQ *error* orig_rotxerror)
  (PRINC "\nViewport locks may have been left unlocked! ")
  (PRINC)
) ;_ end of DEFUN
(DEFUN rotx (pt1 /)			;abase nxent
  (SETQ abase (NENTSELP pt1))
  (IF (AND abase (IF(EQ (CDR (ASSOC 0 (ENTGET (NTH 0 abase)))) "VERTEX")(/=(cdr(assoc 0(entget(entnext(cdr(assoc -1 (ENTGET (NTH 0 abase))))))))"SEQEND")T))
    (IF
      (OR
	(EQ (CDR (ASSOC 0 (ENTGET (NTH 0 abase)))) "TEXT")
	(EQ (CDR (ASSOC 0 (ENTGET (NTH 0 abase)))) "LINE")
	(EQ (CDR (ASSOC 0 (ENTGET (NTH 0 abase)))) "VERTEX")
	(EQ (CDR (ASSOC 0 (ENTGET (NTH 0 abase)))) "POLYLINE")
	(EQ (CDR (ASSOC 0 (ENTGET (NTH 0 abase)))) "LWPOLYLINE")
	(EQ (CDR (ASSOC 0 (ENTGET (CAR abase)))) "LINE")
      ) ;_ end of or
       (PROGN
	 (SETQ basent (ENTGET (NTH 0 abase)))
	 (COND
	   ((EQ (CDR (ASSOC 0 basent)) "LWPOLYLINE")
	    (SETQ lwptslst nil)
	    (FOREACH n basent
	      (IF (EQ (CAR n) 10)
		(SETQ lwptlst (APPEND lwptlst (LIST (CDR n))))
	      ) ;_ end of if
	    ) ;_ end of foreach
	    (SETQ pntcnt 0
		  pntlen (LENGTH lwptlst)
	    ) ;_ end of setq
	    (WHILE (< pntcnt (1- pntlen))
;;;           (princ "\nAngle=")
;;;           (princ (angle (nth pntcnt lwptlst)(nth (1+ pntcnt) lwptlst)))
;;;           (princ "\nAngle=")
;;;           (princ (angle (nth pntcnt lwptlst)(cadr abase)))
;;;           (princ "\nSIN=")
;;;           (princ (SIN(-(angle (nth pntcnt lwptlst)(nth (1+ pntcnt) lwptlst))
;;;                        (angle (nth pntcnt lwptlst)(cadr abase))
;;;                      )
;;;                  )
;;;           )
	      (IF
		(AND
		  (<
		    (ABS (SIN (- (ANGLE	(NTH pntcnt lwptlst)
					(NTH (1+ pntcnt) lwptlst)
				 ) ;_ end of angle
				 (ANGLE (NTH pntcnt lwptlst) (CADR abase))
			      ) ;_ end of -
			 ) ;_ end of SIN
		    ) ;_ end of ABS
		    0.04
		  ) ;_ end of <
		  (< (DISTANCE (NTH pntcnt lwptlst) (CADR abase))
		     (DISTANCE (NTH pntcnt lwptlst)
			       (NTH (1+ pntcnt) lwptlst)
		     ) ;_ end of distance
		  ) ;_ end of <
		  (< (DISTANCE (NTH (1+ pntcnt) lwptlst) (CADR abase))
		     (DISTANCE (NTH pntcnt lwptlst)
			       (NTH (1+ pntcnt) lwptlst)
		     ) ;_ end of distance
		  ) ;_ end of <
		) ;_ end of AND
		 (PROGN
		   (SETQ pt001 (NTH pntcnt lwptlst))
		   (SETQ pt002 (NTH (1+ pntcnt) lwptlst))
		   (SETVAR "SNAPANG"
			   (ANGLE pt001
				  pt002
			   )		;angle
		   )			;setvar
		 ) ;_ end of progn
	      ) ;_ end of IF
	      (SETQ pntcnt (1+ pntcnt))
	    ) ;_ end of while
	   )
	   ((EQ (CDR (ASSOC 0 basent)) "VERTEX")
	    (COND
	      ((EQ (TYPE (CAR (LAST abase))) 'ENAME)
	       (SETQ nxent    (ENTGET (ENTNEXT (CDR (ASSOC -1 basent))))
		     xr_edata (ENTGET (CAR (LAST abase)))
	       ) ;_ end of SETQ
	       (SETVAR "SNAPANG"
		       (+ (ANGLE (CDR (ASSOC 10 basent))
				 (CDR (ASSOC 10 nxent))
			  )		;angle
			  (CDR (ASSOC 50 xr_edata))
		       ) ;_ end of +
	       )			;setvar
	      )
	      (T
	       (SETQ nxent (ENTGET (ENTNEXT (CDR (ASSOC -1 basent)))))
	       (SETVAR "SNAPANG"
		       (ANGLE (CDR (ASSOC 10 basent))
			      (CDR (ASSOC 10 nxent))
		       )		;angle
	       )			;setvar
	      )
	    ) ;_ end of COND
	   )
	   ((EQ (CDR (ASSOC 0 basent)) "LINE")
	    (COND
	      ((EQ (TYPE (CAR (LAST abase))) 'ENAME)
	       (SETQ xr_edata (ENTGET (CAR (LAST abase))))
	       (SETVAR "SNAPANG"
		       (+ (ANGLE (CDR (ASSOC 10 basent))
				 (CDR (ASSOC 11 basent))
			  )		;angle
			  (CDR (ASSOC 50 xr_edata))
		       ) ;_ end of +
	       )			;setvar
	      )
	      (T
	       (SETVAR "SNAPANG"
		       (ANGLE (CDR (ASSOC 10 basent))
			      (CDR (ASSOC 11 basent))
		       )		;angle
	       )			;setvar
	      )
	    ) ;_ end of COND
	   )
	   ((EQ (CDR (ASSOC 0 basent)) "TEXT")
	    (COND
	      ((EQ (TYPE (CAR (LAST abase))) 'ENAME)
	       (SETQ xr_edata (ENTGET (CAR (LAST abase))))
	       (SETVAR "SNAPANG"
		       (+ (CDR (ASSOC 50 basent))
			  (CDR (ASSOC 50 xr_edata))
		       ) ;_ end of +
	       )			;setvar
	      )
	      (T
	       (SETVAR "SNAPANG" (CDR (ASSOC 50 basent)))
	      )
	    ) ;_ end of COND
	   )
	 )				;cond
       ) ;_ end of progn
       (PRINC (STRCAT "\nSelection for ROTX is "
		      (CDR (ASSOC 0 (ENTGET (NTH 0 abase))))
		      ". "
	      ) ;_ end of strcat
       ) ;_ end of princ
    )					;if
    (PROGN
      (SETQ snap_pt2 (GETPOINT pt1 "\nPick second point for Snapang: "))
      (SETVAR "SNAPANG" (ANGLE pt1 snap_pt2))
    ) ;_ end of progn
  )					;if
  (SETQ	rotang (GETVAR "snapang")
	nvwang (* (/ (- (* 2 PI) rotang) PI) 180)
  ) ;_ end of setq
  (IF (>= nvwang 180)
    (SETQ altang (- nvwang 180))
    (SETQ altang (+ nvwang 180))
  ) ;_ end of if
					;  (c:svang)
  (PRINC "\nUse SVANG to set Viewtwist to X-hairs. ")
  (PRINC)
)					;defun ROTX.LSP
(DEFUN c:rotx ()
  (SETQ	orig_rotxerror *error*
	*error*	   rotx_error
  ) ;_ end of SETQ
  (COMMAND ".mview" "lock" "off" "all" "")
  (IF
    (SETQ
      pt1 (NENTSELP
	    "\nSelect Line, Text, or enter first point for Snapang: "
	  ) ;_ end of nentselp
    ) ;_ end of setq
     nil
     (WHILE (NOT (EQ (CAR (SETQ pt1 (GRREAD T 1 2))) 5)))
  ) ;_ end of if
  (SETQ pt1 (CADR pt1))
  (rotx pt1)
  (c:svang)
  (SETQ pt1 nil)
  (COMMAND ".mview" "lock" "on" "all" "")
  (SETQ *error* orig_rotxerror)
  (PRINC)
) ;_ end of defun
(DEFUN c:svang ()
  (IF ukword
    nil
    (LOAD "ukword")
  ) ;_ end of if
  (SETQ	useang (ukword 1
		       "A B 0 Quit"
		       (STRCAT "Twist Angle <A>="
			       (RTOS nvwang)
			       ", <B>="
			       (RTOS altang)
			       " 0, or Quit; def="
		       ) ;_ end of strcat
		       "A"
	       ) ;_ end of ukword
  ) ;_ end of setq
  (COND
    ((= useang "A")
     (SETQ vwang nvwang)
    )
    ((= useang "B")
     (SETQ vwang altang)
    )
    ((= useang "0")
     (SETQ vwang 0)
     (SETVAR "snapang" 0)
    )
  ) ;_ end of cond
  (IF (EQ useang "Quit")
    NIL
    (COMMAND "._dview" "" "tw" vwang "")
  )
  (PRINC)
) ;_ end of defun
;|«Visual LISP© Format Options»
(72 2 40 2 T "end of " 60 9 2 0 0 T T nil T)
;*** DO NOT add text below the comment! ***|;