[1] http://pulzed.com/ [2] https://treksit.netlify.app/credits.html
It has a wikipedia page!
https://en.wikipedia.org/wiki/Planarity
Since Flash is dead I rewrote in JavaScript:
http://johntantalo.com/raphael.planarity/
Here's a short doc about how the puzzle generation algorithm works:
Author: Simon Tatham <anakin@pobox.com>
Date: Sat Jul 16 19:51:53 2005 +0000
New puzzle: `Untangle', cloned (with the addition of random grid
generation) from a simple but rather fun Flash game I saw this
morning.
The game is cool, but I think the title is overly general. It contaons a graph visualizer, which doesn't show much in the way of theory; and it's a railroad, not a playground.
The gotcha thing about this puzzle is sort of greedy approach; try to disentangle the local sub-graphs - concentrate on any nodes of your choice and their connections - and the global graph starts to fall in its place. It's trivial approaching it like this.
I wonder what an algorithmic approach to this would look like, would it act similarly?
The design was ispired by Wold of Goo :)
i also had trouble reading the text on the backgrounds; consider changing the font colour to something that has significantly a different value (as in, Hue-Saturation-Value) from the background.
also as somebody has pointed out, the drag box felt tiny.
Also click on bonus area and then perturb the things.