Sorry, I just realized I only presumed it would only work on curves.
Might have something to do with were it is found in the menus (analyze->curve->curvature graph on)…
Now that I just found this new function, I already have a wish: please add a button to invert the direction of the graphs to make it more usable in non-transparent display modes.
And add another density setting for the number of comb curves independent of iso-curves.
P.S. Sorry to hijack this thread.