> Ps Request : "Helpers lines" can be also " Helpers circles"
> Seems that will be great :)
> Rules and dividers are the bases of geometry :)

Hmmm. But it's not too hard to just draw a circle to use for such a construction, and delete it after you are done...

A line is kind of a special case since a construction line extends infinitely in each direction so it gives something extra (beyond the automatic cleanup) than just drawing a regular line.

A "construction circle" wouldn't really give very much extra benefit over just drawing a regular circle.

- Michael