Probably the best and most comprehensive video about why curvature continuity is so important in product design, what causes those “bumps” on the edges of regularly rounded rectangles, and why it all works as it works.
This is a very nicely presented video, but I discovered it 20 years too late! Back in the early 90’s I was experimenting with b-spline surfaces for car exteriors. I needed to reverse engineer our CAD system, and teach myself to program. There was no internet resources for normal people then, no IT people around either. And I’m no mathematician, so I programmed everything geometrically. Gerald Farin’s book helped with some breakthroughs, but I had to ignore all the heavy formulae. I was finally able to make a program to help create the very precise, smooth surfaces needed for vehicle exteriors seen on many well known cars driving around since then.
Indeed, excellent video.
May I suggest the precursor to this video, by the same creator: