[1] http://pulzed.com/ [2] https://treksit.netlify.app/credits.html
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.
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 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?
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.
The design was ispired by Wold of Goo :)