Calculating a Pipe Invert

[rcb007]

I have the following routine I was working on, and I cannot seem to get it to work.

I was using the links below to try to combine the code into a simpler version.

Object was to select a pipe. Ask for start and end invert and then apply it to the pipe.

Using the center points of the pipe, I needed to take the invert and add half the height of the pipe to calculate the centerline.

The centerline value is value that would update the pipe.

 

;;https://forums.autodesk.com/t5/civil-3d-customization/pipe-inverts-lisp/td-p/6284166
;;https://forums.augi.com/showthread.php?154515-find-pipe-inverts-at-arbitrary-locatio

(defun c:changeinverts ( / _myspace _getparam inv0 inv0 cp0 cp1 cl0 cl1 sel ent obj p0 p1 p0a p1a) 
  (defun _myspace (/ adoc space)
    (vl-load-com)
    (setq adoc (vla-get-activedocument (vlax-get-acad-object)))
    (setq space	(if (= 1 (vla-get-activespace adoc))
		  (vla-get-modelspace adoc)
		  (if (= (vla-get-mspace adoc) :vlax-true)
		    (vla-get-modelspace adoc)
		    (vla-get-paperspace adoc)
		  )
		)
    )
  )
;;;;;;;;;;;;;;;;;;;;;;;;;
  (defun _getparam (obj param)
    (vlax-safearray->list
      (vlax-variant-value
	(vlax-get-property pipe 'pointatparam param)
      )
    )
  )
;;;;;;;;;;;;;;;;;;;;;;;;
  (setq sel (entsel)) ;; Select the pipe
  (setq ent (car sel)) ;; Get the pipe entity name
  (setq obj (vlax-ename->vla-object ent)) ;; Convert pipe to object
  (setq p0     (_getparam obj 0.0)) ;; Get the Pipe Center START POINT
  (setq p1     (_getparam obj 1.0)) ;; Get the Pipe Center END POINT
  (setq height   (vlax-get-property obj 'InnerHeight)) ;;Object Pipe Height
  (setq cp0     (mapcar '- p0 (list 0.0 0.0 (* 0.5 height))))) ;;Calc Half size of pipe at Start
  (setq cp1     (mapcar '- p1 (list 0.0 0.0 (* 0.5 height)))) ;;Calc Half size of pipe at End
  (setq inv0     (getreal "\nEnter Start Invert Line: ")) ;;User Enter Start Invert
  (setq inv1     (getreal "\nEnter Invert Line: ")) ;;User Enter End Invert
  (setq cl0     (/ (+ (inv0) (cp0)) 12.0)))  ;;inv plus half calc pipe size times 12 to equal centerline
  (setq cl1     (/ (+ (inv1) (cp1)) 12.0)))  ;;inv plus half calc pipe size times 12 to equal centerline
  (vlax-invoke-method 
   obj
  'SetStartAndEndPoints
  (vlax-3d-point cl0) ;;Change Start Point to User Centerline
  (vlax-3d-point cl1) ;;Change End Point to User Centerline
  )
(princ))

 

Thank you for the eyes. 

[BIGAL]

I think we need a dwg not sure what your doing, any reason for not maybe using pipe design add on ? They are normally interactive with regard setting invert levels, do way more also.

[rcb007]

Sounds good. Below is the original code.

 

;;https://forums.autodesk.com/t5/civil-3d-customization/pipe-inverts-lisp/td-p/6284166
(defun c:TypeInv ( / sel ent obj p0 p1 p0a p1a)
  ; Select the pipe
  (setq sel (entsel))

  ; Get the entity name
  (setq ent (car sel))

  ; Convert to object
  (setq obj (vlax-ename->vla-object ent))
  
  ; Get the Pipe START POINT
  (setq p0 (vlax-safearray->list
             (vlax-variant-value (vlax-get-property obj 'PointAtParam 0))
           )
  )

  ; Get the Pipe END POINT
  (setq p1 (vlax-safearray->list
             (vlax-variant-value (vlax-get-property obj 'PointAtParam 1))
           )
  )

  ; Calculate new START POINT
  ;(setq p0a (list (nth 0 p0) (nth 1 p0) 10.0))
  (setq p0a (list (nth 0 p0) (nth 1 p0) (getreal "\nEnter Start Center Line: ")))

  ; Calculate new END POINT
  ;(setq p1a (list (nth 0 p1) (nth 1 p1) 11.0))
  (setq p1a (list (nth 0 p1) (nth 1 p1) (getreal "\nEnter Center Line: ")))

  ; Make the changes
  (vlax-invoke-method
    obj
    'SetStartAndEndPoints
    (vlax-3d-point p0a)
    (vlax-3d-point p1a)
  )
  
  (princ)
)

 

TypeInv.dwg

[BIGAL]

So pick 2 points and imply a Y difference not that hard, just move the 2nd circle up the Y difference even if vertical scale involved then draw 2 offset lines based on the new center points of the circles.

 

Please people no code 

 

Rbc007 you have lots of posts have a go yourself, we can help you more if you help your self 1st.