topic Re: ssget not working with short lines in AutoCAD Forum

ssget not working with short lines

bradley_smithZNDND — Thu, 30 May 2024 01:10:51 GMT

Hi guys

I have this problem with a scrip that uses ssget.

The script is supposed to find all intersecting lines and place a point at the intersections.

This works well for all intersecting lines I have worked with so far, but the current file I am processing contains many short crosshairs and these lines are not being processed by the script.

Note that when I grab and resize the lines that make up a crosshair, then the script works and places a point at the intersection. Weird!

This could be a fault of ssget or something else.

I have attached the script and the file.

Can anybody please help?

Thanks in advance.

Re: ssget not working with short lines

bradley_smithZNDND — Thu, 30 May 2024 02:51:24 GMT

UPDATE

I have discovered there is a problem with the sample file that is causing the issue but have been unable to resolve this issue.

The problem is that the lines in the file intlines test.dxf, although having z value 0, are not recognized as intersecting. So, the question becomes, how to flatten this file so that the lines actually intersect.

I have already tried using the flatten command that had some strange results with lines disappearing and I have tried exporting to 12d and then nulling z values and exporting again, but this did not help.

If anyone can solve this problem that would be amazing, as I have just had to place points manually (ok on this small file but a waste of time and doesn't scale to larger tasks).

Thanks again.

Re: ssget not working with short lines

tramber — Thu, 30 May 2024 07:49:26 GMT

You are very far from the 0,0 point.

That's the probable reason you don't find the intersections with the mouse. Firstly.

I had (just) a look in the lisp.

A test between two objetcs at those coordinates and a test with the same close to the general origin should be led.

Re: ssget not working with short lines

tramber — Thu, 30 May 2024 07:56:43 GMT

I did this :

(vlax-invoke (vlax-ename->vla-object (car(entsel))) 'IntersectWith (vlax-ename->vla-object (car(entsel))) 0)

Where your objects are it doesn't work.

Close to the origin, it does 😉

Size of your objects : 0.0439999

Location : 270000,6000000

Sorry...

Re: ssget not working with short lines

bradley_smithZNDND — Fri, 31 May 2024 05:08:56 GMT

😅

Thank you tramber!

Haha, what an obvious solution now you mention it.

I guess AutoCAD just doesn't like coordinates so far from the origin (not surprising given how far away they were).

Re: ssget not working with short lines

tramber — Fri, 31 May 2024 06:07:15 GMT

That's the point. I hit the issue in one shot (due to my experience, age on acad !) but I must say I am a little surprised myself.

The location is far from O, ok, but not that much...

(looking for an emoji...)

😶