Take a close look...

That's two!, you've probably said. And how did you know, even though there is only a single line? You've probably spotted the continuity break at the very bottom of the drawing.

In design, continuity breaks are problems that are not straighforward to solve. And worse: even an untrained eye - or a random customer for that matter - can spot the edge in the design easily. Imagine you design a typography that is printed on wall of KaDeWe. In other words: You would not want your letter o to have sharp edges when it's plotted on a 30 meter advertisement.

This is why designers took a closer look into what's called curvature. It turns out: continuity breaks are nothing else than jumps in curvature from one arc to the next. And even more: Once the curvature is visualized, the solution space becomes clear.

Et Voilà 🧑‍🎨

The magnitude of the curvature is visualized by the length of the lines perpendicular to the arc. The longer the lines, the bigger the curvature.

Take a look a the junction of both arcs: The left arc ends with a huge curvature. In contrast, the right arc starts with a comparably small curvature. The jump in curvature is why you see an edge in the line.

Let's fix that 🎨

Great job! The curvatures now match.

This was achieved by easing the end of the first arc. Check out my Curvature Figma Plugin to see the effect on your own designs.

Let's take a look again...