Rhino sometimes - but often doesn t - find a final target point, for a fillet - surface that would be geometrical the right position for a fillet like above screenshot shows.
there is nice tutorials how to solve / repair those issues:
https://wiki.mcneel.com/rhino/advancedfilleting
https://wiki.mcneel.com/rhino/tancylinders
And i totally see, that there are many cases that can t be decided by an algorithm within the tolerance…
(A) → Bug
But if one of the surfaces is planar (like example in Screenshot… the algorithm might be able to find the point with same normal …) so maybe still some improvement possible here (…Bug)
(B) → Wish
But even if the alogrithm can t find those points - there is a human infront of the screen … so there is my wish:
After Picking the two surfaces - the filletSrf command should check if the resulting surface is getting very narrow (100 times document absolut tolerance) / or (the same) if the surfaces have nearly a common normal (10 times document angle tolerance) at their intersection.
Only if this is the case, there should be an additional step in the dialog:
“do you want the FilletSrf to end / start in a specific point ?” (pick no point → ignor) then the user could pick one or two points… the resulting fillet should target this point
this would be fantasic and safe a lot of work…
maybe a similar step could be implemented in the more complex filletEdge…
thanks - kind regards - tom