I found a way to do that.paddle wrote: ↑Mon Jan 24, 2022 5:53 pm It's because of the way the tool works. It actually creates the constraint at every step. Then delete and recreate the constraints on each steps. And if the tool abort (right click) then it delete the last seen constraint.
So the vertical/horizontal would get applied (as the equality for 2+ circles is which is not ideal) and the geometry would update to be vertical/horizontal. Even if the tool abort and the constraint is deleted the geometry would have moved.
Or I need a way to cancel (ctrl-z not just delete) the vertical/horizontal constraint. Is that possible from the code?
Now if the tool is aborted, all changes are undone. Also it let us change of constraint mode.
So I removed the 0/90 angle replacement by parallel/perpendicular and added shift alternative when 2 lines are selected.
Branch has been update if you want to try modifications and help spot errors/bugs.