Not getting Osnap

I am writing a routine that is a series of autocad commands wrapped in a
defun. I would like to force an osnap at certain points in the commands
where you would be pausing for user input, but can't figure out how to do
it. Below is the routine. Before anyone comments on the formatting of the
program, the book I am using to teach myself (ABC's of AutoLISP) uses this
convention and it makes sense to me. I would like to use NEAREST when
setqing p1 & p2 and use ENDPOINT when completing A2 (this would snap to the
end of the arc of A1). I have another issue with the routine, but if I
could get help with these items I would be very appreciative.

(defun c:slo (/ osold)
(setq osold (getvar "osmode"))
(setvar "osmode" 0)
(LS)
(A1)
(A2)
(L1)
(setvar "osmode" osold)
)

(defun LS ()
(if (not (tblsearch "layer" "slope"))
(command "-layer" "n" "SLOPE" "c" "1" "SLOPE" "s" "SLOPE" "")
)
)

(defun A1 (/ p1)
(setq p1 (getpoint "\nPick start point for first ARC: "))
(command "_.arc" p1 pause pause)
)

(defun A2 (/ p2)
(setq p2 (getpoint "\nPick start point for second ARC: "))
(command "_.arc" p2 pause pause)
)

(defun L1 ()
(command "_.line" "" pause "")
)

 

Before the command set the osnap mode to what you need.

(setvar "osmode" 1) ; endpoint
(setvar "osmode" 2) ; midpoint
(setvar "osmode" 3) ; endpoint,midpoint
(setvar "osmode" 4) ;center
(setvar "osmode" 5) ; endpoint,center
etc.....

You should also use (setq osmode (getvar "osmode")) before setting osmode
and (setvar "osmode" osmode) at the end of the function so that it is reset
to whatever the user was using.

 

I tried setting osmode prior to each function, but I don't want them to be
running. I would like to emulate the command line way of doing things by
issuing the "nea" override and have it go away. I have tried placing the
"nea" where the "pause" is, but it didn't work correctly. Can a setvar be
nested inside of a command call? If so, how would it be written?

Also I believe that I am using a setq osmode. Mine is called osold however.

 

Since you're using the (command ...) function, just insert the OSnaps in the
command string, as if you were entering it from the Command: prompt. IF that
doesn't work, then something else is amiss.

(command "_.line" "_nea" pause ... <etc.> ...)
___

 

I have been trying that to no avail. I will keep plugging away and see if I
can find the amiss.

Thank you Paul.

 

The problem with (command ".line" "nea" pause ...) is that the "nea" only
works for the first point.
The command line override should work with the osmode set. It is no
different than setting the osnaps before you start a command at the command
line.

(defun A1 (/ p1)
(setvar "osmode" 512)
(setq p1 (getpoint "\nPick start point for first ARC: "))
(setvar "osmode" 0)
(command "_.arc" p1 pause pause)
)

(defun A2 (/ p2)
(setvar "osmode" 1)
(setq p2 (getpoint "\nPick start point for second ARC: "))
(setvar "osmode" 0)
(command "_.arc" p2 pause pause)
)

(defun L1 ()
(setvar "osmode" 0)
(command "_.line" "" pause "")
)

Or if you don't like setting osnaps then you could do this:

(defun A1 (/ p1)
(setq p1 (osnap (getpoint "\nPick start point for first ARC: ") "nea"))
(command "_.arc" p1 pause pause)
)

(defun A2 (/ p2)
(setq p2 (osnap (getpoint "\nPick start point for second ARC: ") "endp"))
(command "_.arc" p2 pause pause)
)

 

Thanks Jim. I took the same approach you did in the first section. The
only problem I seem to have now is that I can't make L1 work correctly.
When I do this:

(defun L1 ()
(command "_.line" "_endp" "_perp" "")
)

I get this:

_.line Specify first point: _endp of _perp
Invalid point.
; error: Function cancelled
Specify first point:

I've placed a pause in front of each osnap, but what happens then is that no
osnap is set for the first pick, endp is set for the second, then the line
command ends.

Any other thoughts?

 

pause *after* osnap ?
(command "_.line" "_endp" pause "_perp" pause "")

 

Well that seems to have worked! Thank you so much Mark! I don't know why I
didn't think to try that myself.

Jeff

 

You're welcome

Glad to help

 

You're leaving out the pauses.
___

 

Figured that out. Thanks for continuing to look for my errors.

Jeff

 

Method 1:
Set osmode to 512 before getpoint P1
Set osmode to 1 before getpoint P2

(defun A1 (/ p1)
(setvar "osmode" 512)
(setq p1 (getpoint "\nPick start point for first ARC: "))
(setvar "osmode" 0)
(command "_.arc" p1 pause pause)
)

Method 2:
Use (osnap pt mode)

(defun A1 (/ p1)
(setq p1 (getpoint "\nPick start point for first ARC: "))
(setq p1 (osnap p1 "_nea")
(command "_.arc" p1 pause pause)
)

This method is dangerous because (osnap pt mode) will give NIL if Autocad
will not find an object that is nearest to p1.

JanC