Usually, a pattern can be defined by its two ends.
For example, your transition may be defined by two polylines e.g., an irregular pentagon as the base [end 1] and an oblique ellipse as the top [end 2]. It is easy to generate both in AutoCAD or GStarCAD.
Place them in your CAD's 3D space according to your needs.
Start LITIO 2.0, choose this option [Free pattern from two 3D curves], click on both entities, define some few parameters [thickness and internal fillet radius], and you get the resulting 3D
developable surface [if it 'mathematically' exists] and its development.
You can create transitions just by clicking any two valid entities (either 3D meshes created by Litio 2.0; or 2D and 3D
polylines; or circles, located in AutoCAD/GStarCAD's 3D space.*
Thus, LITIO 2.0 gives you much more transitions than the ones available through its standard dialogue boxes.
* Some restrictions apply [see user manual]. Note, that the following entities are not accepted: arcs [convert arcs to polylines using the PEDIT command] nor ellipses [use ellipse pattern of LITIO 2.0], and resulting 3D objects cannot have concavities.
We are able to get all what we needed out of the software. We use AutoCAD, so it is nice that the software works within that program. (...) Very good value for money! Great software!
Evansville Sheet Metal Works
Evansville, IN - USA
How to draw a customized sheet metal transition with LITIO2
You can draw customized sheet metal transitions just by picking two valid entities.
For this particular case, the transition is defined at its base with a polyline that is made by one third of a circle, two lines from the arc ends to the arc center, all with a fillet radius, and a circle at the top.