Adding a transparent command

I'm over my head. Here's what I have:

(defun btw( / p1 p2 p3) ;point between two pick points
(setq p1(getpoint "\nFirst point: "))
(setq p2(getpoint p1 "\nSecond point: "))
(setq p3(polar p1 (angle p1 p2) (distance p1 p2)))
(princ)) ;defun

(vlax-add-cmd "btw" 'btw "ACRX_CMD_TRANSPARENT")

What I'd REALLY like to do is add an osnap. But keying in 'btw will do.

help.

rs

 

Oops, here it is, corrected:

(defun btw( / p1 p2 p3) ;point between two pick points
(setq p1(getpoint "\nFirst point: "))
(setq p2(getpoint p1 "\nSecond point: "))
(setq p3(polar p1 (angle p1 p2) (/ (distance p1 p2) 2)))
(princ)) ;defun
(vlax-add-cmd "btw" 'btw "ACRX_CMD_TRANSPARENT")

 

Ok, scratch that. Here it is corrected correctly:

(defun btw( / ) ;point between two pick points
(setq p1(getpoint "\nFirst point: "))
(setq p2(getpoint p1 "\nSecond point: "))
(polar p1 (angle p1 p2) (/ (distance p1 p2) 2))
) ;defun

(vlax-add-cmd "btw" 'btw "ACRX_CMD_TRANSPARENT")

 

Simpler way: add this into the **SNAP section of the ***POP0 part of the
menu (reassemble into one line):

ID_OsnapMid2 [Mid of &2]^P(list (/ (+ (car (setq A (getpoint "1st POINT:
"))) (car (setq B (getpoint "2nd POINT: ")))) 2) (/ (+ (cadr A) (cadr B))
2)) ^P

I put it just after the Midpoint line. Doesn't require typing anything in.
Just bring up the on-the-spot Osnap list, and there it is. I also have one
that does a fractional distance between two points (if you want to use, for
instance, 3/4 of the way from one point to another -- you tell it what
fraction), if you're interested.

 

Simpler way: add this into the **SNAP section of the ***POP0

Kent, that looks like a great approach, but does this override running
osnaps? I once used a function much like krispy's, but without the temporary
osmode=0. It worked fine as long as I was designating a point in empty
space, but if the "midpoint" happened to fall on an object, running osnaps
could cause a different point to be selected -- for instance if an endpoint,
midpoint, or quadrant happened to fall withing snapable distance. I had to
add the temporary osmode=0 to prevent this.

 

What version of AutoCAD are you running?
AutoCAD 2005 has mid2 and m2p built in.

 

I have 2005...please tell me how to use it.
I get ; error: no function definition: MID2

Gary

 

That is odd, works fine here.

Command: l
LINE Specify first point: mid2
First point of mid:

Command: l
LINE Specify first point: m2p
First point of mid:

Any customization getting in the way?

 

You're right, you have to be aware of that. This routine goes way back,
long before running Osnaps. I've been lazy enough to not "fix" it, but have
just gotten used to hitting F3 before I pick the second point, if I have
running Osnaps on. And I'd be inclined, rather than to temporarily do
Osmode=0, to add that value to OSMODE (I forget what it is without looking
it up) that is the equivalent of hitting F3 (disables the running mode
without changing your set combination). Some day....

 

add that value to OSMODE (I forget what it is ...

LOL I've got a few myself that I keep meaning to update with the "F3
number" -- but I think it takes a bit of logand business, and that always
requires a little refresher too. "Some day" maybe I'll figure it out and
tuck it away as a library routine for the occasions when I want it.

 

Man, learn something everyday.
Works fine...I was just doing it wrong..

Gary

 

Stupid me I was using (mid2)

I'm still on my second cup....stayed up too late.

Gary

 

Glad it works, but... what were you doing to get
the "no function definition" error? If anything, I
would think you'd get an "unknown command".

 

Thank you all. Don't know whether I want to add it to the osnap list yet.

Krispy, you have caused an epiphany; it never occurred to me to deliver a point
to a command via (Command). Ya live and learn. Point of order: why do you not
need to use !midxy, as you would from the keyboard?

So, what about
(vlax-add-cmd "btw" 'btw "ACRX_CMD_TRANSPARENT")?
Is that excess baggage -- or am I even using it correctly?

rs

 

Sorry... don't know much about all the vlax commands, I went straight from basic lisp stuff to VBA.
As to the other... when your "in" the lisp you are passing the variable, so that AutoCAD doesn't see "(command midxy)" but sees "command: xx,yy,zz" with whatever the point is. When you are at the command line AutoCAD doesn't know whether you are going to type the point or a variable name, so it assumes you are giving it the point. We have to tell AutoCAD that we are going to give a variable name but prefixing it with an exclamation point.
Hope that helps and doesn't confuse instead.

 

But watch out if you have polar tracking turned on! If your resulting point
is 'close enough' (determined by aperture) to one of your tracking angles,
it will 'snap' to it. Just FYI.