Bivector.net
Implementing computer graphics should be done with geometric algebra.
I don't know anything about this field but I know the difference between a clean, consistent API and a random hodgepodge of hacks.
Since I don't know anything I'm not sure if GA allows you to avoid errors such as the one in the article but in typical HN fashion I'll be derailing with some left- field claim and a link to some other project.
Also check out Grassmann.jl at https://github.com/chakravala/Grassmann.jl