;setvar cmdecho shortcut
(if (= echo nil)(defun echo( temp / )	(setq old_cmdecho (getvar "cmdecho"))(setvar "cmdecho" temp)))
;set undo shortcut
(if (= undo nil)(defun undo( temp / )(command "undo" temp)))
;radians to decimals
(if (= rtd nil) (defun rtd (a) (/ (* a 180.0)pi)))
;decimals to radians
(if (= dtr nil) (defun dtr (a) (* pi (/ a 180.0))))

;#################
;###   Twist   ###
;#################
;v. 1.5

;<<<< ADD >>>>>
; option to do a dview, twist on a viewport when in a paperspace
; if paperspace, then do this
; if not in an active layout
;		set unactive flag
;		select viewport & make active
; if layout is locked
;	set a locked flag
;	unlock
; command dview twist, realign ucs option
; put everthing (besides twist) back the way it was


;Command : TW 
;  shortcut for dview twist (with added functionality)
;  Enter the twist angle explicitly or
;  Align: set twist angle by picking two points (Point 1 is 0,0 and Point 2 is positive x-axis vector)
;  Relative: set twist angle relative to current twist angle
;	 After twisting the view, the list will prompt (yes/no) to Realign UCS.  Default 



(defun c:tw( / answer )
	(echo 0)(undo "begin")

	(setq answer (getstring carriage_return "Specify angle or [Align/Relative]: "))

	(if (or (= answer "") (= answer "a") (= answer "A"))
			(setq answer (- (rtd (getvar "ViewTwist")) (rtd (getangle "Pick first point:")))))

	(if (or (= answer "R") (= answer "r"))
			(setq answer (+ (rtd (getvar "ViewTwist")) (getint "Specify angle relative to current view: ")))  
			)


	(command "dview" "" "twist" answer "" )
	(initget "Yes No")
	(if (/= (getkword "\nRealign UCS?: [Yes/No] <Yes>:") "No" )
			(command "ucs" "v"))
	(undo "end")(echo old_cmdecho)
	(princ))