Art,

Do you mean temporarily add in more snap alignment angles while in the construction line tool?

Currently the default alignment angles are +-0,90 and creation angle is +-45.

Tim

In SW's, construction lines are created by arbitrarily drawing a construction line, then using smart dimension to input the angle that the construction line is at an angle too (if you get what I mean?). So instead of having a snap, you can just for example enter 28 or 36 or 23.7 etc etc.

Snapping in Macdraft on the other hand, uses a series of predetermined angles of which are similar to what has been suggested here. QCad, I draw a line, and then add a line at a predetermined length, and at a predetermined angle to that line.

I don't really know what is better? (I suppose it's a matter of experience, something I could definitely get more of!). However I do like the suggestion of a construction line that goes off to infinity, because I too am always having to lengthen these lines too. I suppose there could be a way of shortening the length of the line later, by using the scissors tool or something? Incidentally, if you take a line off a construction line in SW's you get a proper line, rather than another construction line.