Posted by gravo-mm on Jan 08, 2016; 9:03pm
URL: https://forum.librecad.org/Converting-Selection-to-Polyline-tp5712769p5712803.html

It occured to me that I mostly worked with this special subtype of polylines: closed polylines.
That's why I didn't really need control over the starting point of a polyline.
However, I would consider this flow user interaction for the specification of a new polyline helpful:

                                                user starts convert
                                  option(like trim with fillet): force closed
                                      selection tools as with "hatch"
                                             user presses enter
selected closed polyline:                                  selected non-closed polyline;
create with any starting point                          fail if force enabled (inform: gap between... etc.)
                                                                  else have user click starting entity
                                                                  create polyline

Note that the currently used auto-finding of touching entities will still be available via "select contour".

By "closed polyline" I mean any polyline with < 2 segments whose starting and ending entity touch.
"force closed" to reject non-closed polylines would be useful for editing dxf files converted with other
software, because these sometimes have small gaps between entities, visible only with deep zoom.

I'm also thinking of some other useful polyline operations and will soon create a subject about these.