lisp for trimming/ breaking a polyline or line

[piterfun7777]

Hi guys, just new to the autolisp world and would like to ask your assistance in making a lisp so it can be a basis for my future lisp programs.

Here is the flow of the lisp.

Overview: the lisp trims or break a polyline or a line a the point (midpoint) indicated by the user by a value specified by a user.

The distance value indicated should be followed even if the polyline or line is angled.

First: the user is asked of how much the value of the trim/ break to be done on the polyline or line.

2nd : the user is asked to chose the point where the trim / break will be done.

3rd: click the next point on the line or polyline or press esc to exit.

Sample, I inputted 1000mm for the value and click at the midpoint of the polyline, the trim should be 500mm on both side of the polyline.

As long as I don’t cancel, I will just continue to choose the next point to trim/ break.

Thank you in advance and more power

[BIGAL]

The line is easy just pick your pt say center as part of this it returns the object via entsel so you can get start & end pts, get angle of line, do 2 quick polars and you have your break points.

 

The pline a lot more complicated if you want it broken and pline section is short I am sure others will advise. 1 routine should do both objects. Ps I am interested in this also for something else to do with plines.

[tombu]

I think he's got it: http://forums.augi.com/showthread.php?161739-Lisp-to-trim-break-a-polyline-or-line