[lucianbr]

In what sense is the Duke Nukem thing "an example of this"? The duke thing is an internally consistent programmed behaviour, this is... just random errors caused by a random change in the source code. Duke is maybe non-euclidean geometry, or something. This doom pi thing is... nothing to do with geometry. More an example of "garbage in, garbage out" maybe.

[ColinDabritz]

It's an example of "non-euclidean" space, and yes, it is a bit different than the article.

[snthpy]

The DN example would be an instance of non-Euclidean topology whereas the other one is presumably non-Euclidean geometry.