Hi, I don't know if this has been suggested but some kind of 'Boundary' tool where you click inside a set of lines and and a closed polyline is created would be quite useful.

Have a great Weekend!

Marc

Hi Marc - select all your curves there and use Construct > Boolean > Union, does that do what you need there?

This may need some tuning up for concave outlines I think, but there is stuff in boolean union for doing this task.

- Michael

Hi Michael, Yes this definitely works, thanks.

I did not thought that Boolean operations worked with open curves.

Excellent functionality!

Marc

And selection by loops? (after select 2 edges for give the direction)

Hi Marc,

> I did not thought that Boolean operations worked with open curves.

Yeah there are several situations where open curves can be used.

Another one is they can be the objects that get cut by closed curves in a difference or intersection command.

Like for example here are some open curves (lines) that cross over some closed curves:



You can select those open curves and then do a difference or intersection with the closed curves.

Here is difference:



Here is intersection:




Another thing that can work is to have a grid of crossing open curves, like this:



Then boolean union should be able to form closed curves for each cell (I dragged the result curves a little bit apart for illustration):




However, the curve booleans can tend to be a bit buggier than the regular booleans, you may sometimes run into a stray edge that needs to be cleaned up with the unioning.

- Michael

Hi Pilou,

> And selection by loops? (after select 2 edges for give the direction)

Normally a loop is defined by curves that have endpoints that touch - if you look at Marc's example notice that the endpoints do not touch...

In the future I do want to add some kind of loop selection helper, but I do not expect for it to handle this kind of intersecting (rather than end-to-end touching) situation though.

- Michael

Hi Michael,

Thanks for the examples, I'll let them simmer till I understand them.
I am still not used to using 3d tools in 2d, old habits!

A loop-chain selection would be handy.
I imagine it could also work on a 3d face if you click on an edge.
Maybe a double-click could invoke it.

Marc

Yes, I vote for the double click loop selection, I'm quite used to that :)

Yes me too ...

..and also click two edges then use up arrow to extend selection (another modo user :-) )

Hi Michael,

I've been playing around a while with 2d Boolean and it's quite handy.
I just got an open curve for result at one moment.

I was wondering why didn't you fused "join" and "boolean union" in one command?

Marc

Hi Marc,

> I was wondering why didn't you fused "join" and
> "boolean union" in one command?

Well, the booleans are more intended to be used when objects need to be intersected and have some portions removed in order to finish the procedure.

Join on the other hand does not attempt to do any cutting, it only tries to glue things together at their existing endpoints (for curves) or edges (for surfaces).

This kind of makes Join in a certain sense more simple and it can possibly be more robust since it is more focused on just that task instead of also adding intersection calculations into the mix.

- Michael