Selecting random number of multiple points - AutoLISP/VBA..

[basepointdesignz]

Hi guys and gals,

How do I code in AutoLISP and/or VBA to allow the user to select multiple points on screen and use them as a point-list for a polyline (actually I want to use the command like the area command only, this one will convert the fiqure to metres-square and insert the answer as text).. Now this point list can be an random amount depending on what the user selects..

Any ideas,

Cheers,

Renegade.. BULLET-PROOF DESiGNZ
renegade@tiscali.co.uk
+447919 117062 (mobile)

 

[CarlAK]

Here's a lisp approach:

(setq ptlist nil)
;;following while loop builds a point list of
;;each selected point
(while
(setq pt (getpoint "\nPick a point: &quot)
(setq ptlist (cons pt ptlist));add point to fron
)
(setq ptlist (reverse ptlist)) ;reorder points, first to last

Now you can work this point list into an "area" command within the routine

 

[basepointdesignz]

Thanks CarlAK,

I'll try that out..

As I'm new to AutoLISP, I'm hazarding a guess at the next line here:

(COMMAND "_area" plist " ")

Also, wouldn't you have to have a WHILE argument, like:

WHILE (/= pt nil)

....or does the way you wrote stop the command on a nil entry?

Cheers,

Renegade..

BULLET-PROOF DESiGNZ
renegade@tiscali.co.uk
+447919 117062 (mobile)

 

[CarlAK]

DJR,
Yes, your code should return the area. The last "" should have no space between quotes. And yes the way it was written, creation of the ptlist would end on a nil (return). Then to get the area, use

(setq PtsArea (getvar "area&quot)
..which gives you area in current units.

Another way to collect points from user is from within the "area" command:

(command "area"starts the area command
(while (/= (getvar "cmdactive&quot 0);;loop while there is input
(command pause);;pauses for user input
);while

then get the area in the same way.

Have fun,

Carl