[namanyayg]

The concept you're talking about is a Hilbert Curve. But this is the first time I've heard it applied to analogue tv.

https://en.m.wikipedia.org/wiki/Space-filling_curve

[flir]

Yeah, in my memory the pattern was specifically a Hilbert Curve but rotated 45deg (that can't be right, can it? That would just make things harder). I must have seen it between 1987 and 1997.

Ah! Found this: https://www.ripcorddesigns.com/blog-news/who-needs-rastas-an... - there's even a patent! I was searching on space-filling curve, not Hilbert curve.