Hi Felix, that's a great result!
Yes, using flow mapping from a base curve to a target curve can make it a bit easier to apply a bend only in one direction at a time and minimize distortion.
> Maybe you have already something in mind to facilitate
> this kind of 2 curves bending.
Well, just using the flow command twice in sequence seems like it does the job for this case quite well already.
Do you mean having some special option just for the convenience of a couple of less clicks?
It's not generally very good from a UI design standpoint to stick in a whole ton of custom options for doing specific things that can already be done pretty easily with just a couple of actions in sequence - that tends to lead to UI bloat making the UI get overly filled up with specialized stuff and a UI that is totally chock full of stuff is more difficult to use.
See this previous post for some more explanation on this UI problem:
http://moi3d.com/forum/index.php?webtag=MOI&msg=4442.19
The philosophy of "more is better" does not really apply very well to UI design, at least in the case of trying to keep things easy to use which is a big focus for MoI.
So if you are able to get a good result for this case by using the technique of using flow twice in sequence, then that's what I would consider to be a successful setup already.
What you're talking about there should amount to only a few seconds to apply the flow command a second time, right? Shaving a few seconds off of a construction technique like this is not really a significant improvement. Compared to all the other setup that you're already doing it's not really a significant stumbling block and all together the overall technique is saving a whole lot of time compared to constructing the warped object directly without any use of flow...
But you could probably use surface to surface flow to expedite this if you made a target surface that was not pinched together - that would be something like take these 2 crossed curves that you have here:
You can use the Sweep command to build a curved surface from those that is more uniformly shaped and not pinched near the top or bottom, that should help to minimize distortion in surface-to-surface flow.
Select one of those curves for the sweep profile, then run Construct > Sweep and select the other curve as the rail, that will build a curved but not pinched surface that looks like this:
This kind of surface that does not have pinched together areas in it will reduce distortion when using it as a flow target.
Basically if you want to do a 2 directional flow, that is what the surface to surface flow will do already, just try to make the surface have a more uniform semi-rectangular layout to it and don't pinch parts of the surface to be narrower or wider than other parts.
- Michael