Offset, Trim commands in Lisp

[ready2goriding]

These commands are not working very well. Is there somewhere I can look for instructions pertaining to their use in lisp routines? None of my currently bookmarked sites seem to go into much detail.

Thanks, doug

[Lee Mac]

What is going wrong? What code is causing the error?

 

There are alternatives - like vla-offset for example, but lets see if we can resolve your issues first

[ready2goriding]

I don't think it is a particular code as much as it is my ignorance. For example, I do not know how to select the line to offset in my routine, can't seem to select the proper trim lines, etc. I haven't tried many commands besides lines & arcs yet with my routines, so I am basically looking to expand- however I cannot make the commands work. Does that make any sense?

Thanks, doug

[ready2goriding]

To clarify, I was trying to select points because I'm not sure how to select lines from within my lisp routines. That doesn't seem to work!

[alanjt]

Very very very simple example of using the Offset command within LISP.

 

 

(defun c:TEst (/ dist ent pt)
 (and (setq dist (getdist "\nSpecify offset distance: "))
      (setq ent (entsel "\nSelect object to offset: "))
      (setq pt (getpoint "\nSpecify point on side to offset: "))
      (command "_.offset" dist ent "_non" pt "")
 )
 (princ)
)

[ready2goriding]

I see now. I was trying to get fancy and have the program do all of the work. I didn't want to have the user select anything with the exception of top & bottom center points. I will explore "entities" further and see if that can fix me up!

Thank you, alanjt!

[alanjt]

I see now. I was trying to get fancy and have the program do all of the work. I didn't want to have the user select anything with the exception of top & bottom center points. I will explore "entities" further and see if that can fix me up!

Thank you, alanjt!

You'll have to post an example. I am completely lost to what you just said. We are more than happy to help.

[ready2goriding]

Good point. I confused myself a little...

 

This box represents a cabinet. My lisp will eventually add or subtract length to the cabinet while keeping the end compartments at a constant dimension. To make it interesting, the center divider at the top is a constant also.

I chose to achieve this by:

1- draw a center line from top to bottom.

2- offset 8" to either side in order to clear the top, center compartment.

3- offset each of these new lines 6" to the outside, and trim the top & bottom lines between them.

 

I hope this helps, doug

TesT.dwg

[ready2goriding]

I think I am starting to understand. I was attempting to make the offest command automatically enter it's own numbers and points. I guess the user (me!) still has to supply the inputs that the command needs to run. I can work with that! Thanks for the help, all!

Back to it...

[ready2goriding]

Very very very simple example of using the Offset command within LISP.

 

 

(defun c:TEst (/ dist ent pt)
 (and (setq dist (getdist "\nSpecify offset distance: "))
      (setq ent (entsel "\nSelect object to offset: "))
      (setq pt (getpoint "\nSpecify point on side to offset: "))
      (command "_.offset" dist ent "_non" pt "")
 )
 (princ)
)

 

 

Can someone please tell me what the "(and)" function is? This may be my whole problem? Thanks, doug

[Lee Mac]

Its Alan's way of making testing for null user input - it works as the AND statement will stop evaluating expressions as soon as it reaches an expression that returns nil. But I don't like that construct in a whole program IMO.

[ready2goriding]

Its Alan's way of making testing for null user input - it works as the AND statement will stop evaluating expressions as soon as it reaches an expression that returns nil. But I don't like that construct in a whole program IMO.

 

 

I see, thanks. I guess that wasn't my problem! lol

[fixo]

I see, thanks. I guess that wasn't my problem! lol

I don't understand what you exactly need

Just a quick code:

(defun c:ofc (/ ang cp1 cp2 en1 en2 ent1 ent2 obj1 obj2 tp1 tp2 up1 up2)

 (setq ent1 (entsel "\nSelect first line : ")
ent2 (entsel "\nSelect second line : ")
en1 (car ent1)
en2 (car ent2)
obj1 (vlax-ename->vla-object en1)
obj2 (vlax-ename->vla-object en2)
cp1 (vlax-curve-getclosestpointto obj1
      (vlax-curve-getpointatparam obj1
 (/ (- (vlax-curve-getendparam obj1)(vlax-curve-getstartparam obj1)) 2)))
cp2 (vlax-curve-getclosestpointto obj2 cp1)
ang (angle cp1 (vlax-curve-getstartpoint obj1))
up1 (polar cp1 ang 2);<-- 2 is offset distance
up2 (polar cp1 (+ pi ang) 2)
tp1 (polar cp2 ang 2)
tp2 (polar cp2 (+ pi ang) 2)
)
 (command "._line" "_non" up1 "_non" tp1 ""
   "._line" "_non" up2 "_non" tp2 ""
 )
 (princ)
 )
(vl-load-com)
(princ "\n   ***  Start command with OFC to excute   ***")
(prin1)

 

On the picture should be Select first line, Select second line

 

~'J'~

[ready2goriding]

Hi, fixo! I am just trying to understand how to make a "trim" command work in lisp. I am a lisping rookie- as you can tell! I will study your code and see if I can understand anything that I am missing. That may take a while...

 

Basically, when I right-click to enter my trimming selections- the function ends. There is much in your code that I do not comprehend yet, so I may have jumped into this project too early...

Thank you, doug

[alanjt]

Its Alan's way of making testing for null user input - it works as the AND statement will stop evaluating expressions as soon as it reaches an expression that returns nil. But I don't like that construct in a whole program IMO.

Many people use that method.

The only other logical way you could write that would be to use

(if (and the 3 prompts) (offset))

but in that situation, you've only added an an additional check. AND would be required either way.

[ready2goriding]

I thought that would end the nils?

[Lee Mac]

I'm not sure what you are saying - the princ is not within the AND statement, and, when called without a string or file descriptor, will return a null symbol ( "" ).

[ready2goriding]

I'm sorry. Confused between "exit cleanly" & "nill".

Totally silly of me... I've been real silly on this learning curve so far.

[ready2goriding]

Very very very simple example of using the Offset command within LISP.

 

 

(defun c:TEst (/ dist ent pt)
 (and (setq dist (getdist "\nSpecify offset distance: "))
      (setq ent (entsel "\nSelect object to offset: "))
      (setq pt (getpoint "\nSpecify point on side to offset: "))
      (command "_.offset" dist ent "_non" pt "")
 )
 (princ)
)

 

 

Would it be possible to post a similar example of the "move" command, or point me towards a routine that contains it? I am having no luck with this command at all, and can't seem to find any examples... I hate being the rookie- still!

Thanks, doug

[Lee Mac]

A very simple code using Move - obviously this code is redundant, with no advantage over the move command, but it serves as an example.

 

(defun c:test ( / ss p1 p2 )
 
 (if (and (setq ss (ssget "_:L"))
          (setq p1 (getpoint "\nSpecify Base Point: "))
          (setq p2 (getpoint "\nSpecify Next Point: " p1)))
   
   (command "_.move" ss "" p1 p2))
 
 (princ))