;;;Elise Moss
;;;www.mossdesigns.com
;;;September 2007
;;;This routine asks the user to enter two elevations, select two points for distance
;;;and then labels the midpoint of the distance
					; Convert value in radians to degrees
(defun Radian->Degrees (nbrOfRadians)
  (* 180.0 (/ nbrOfRadians pi))
)


(defun c:elev-lab ()
  (setq elev1 (getreal "\nEnter first elevation: "))
  (setq elev2 (getreal "\nEnter second elevation: "))
  (setq pt1 (getpoint "\nSelect first point: "))
  (setq pt2 (getpoint pt1 "\nSelect second point: "))
					; calculate distance between the points
  (setq x-dist (distance pt1 pt2))
					; next calculate the distance between the elevations
  (setq z-dist (- elev1 elev2))
  ;;now get the angle
  (setq arctan-val (/ z-dist x-dist))	; this is in radians
  (setq elev-angle (atan arctan-val))
					; convert radians to degrees
  (setq degrees-val (Radian->Degrees elev-angle))
					; convert angle to positive number
  (setq degrees-val (abs degrees-val))
					; convert angle to string
  (setq degrees-val (rtos degrees-val 2 2))
					; convert distance to string
  (setq x-dist-string (rtos x-dist 2 2))
					; get degree symbol
  (setq deg-symb (chr 176))
  ;;now we have to construct the text which will be dist < angle
  (setq elev-text (strcat x-dist-string " LF @ " degrees-val deg-symb))
					; locate midpoint of two points selected
  (setq x1 (car pt1))
  (setq x2 (car pt2))
  (setq y1 (cadr pt1))
  (setq y2 (cadr pt2))

  (setq midx (/ (+ x1 x2) 2))
  (setq midy (/ (+ y1 y2) 2))
  (setq mid-pt (list midx midy))



					; time to place the text
					; need to know if the text has a height defined
  (setq th-flag (getvar "TXTSIZE"))
  (if (= th-flag nil)
    (command "text" "j" "c" mid-pt "" "" elev-text "")
  )
  (if (/= th-flag nil)			; the textsize defined, only need to set rotation
    (command "text" "j" "c" mid-pt "" elev-text "")
  )






)					; end defun