Got completely stuck on part 2. Tried some polygon
area calculations, but none provided the correct
answer, most likely due to the unorthodox polygon
points.
I also tried _shoelace method_ without any luck.
Had not heard about that one earlier, it was a good
learning experience even though I vould not use it
here.
By the subreddit, several people had had luck
using the ray method.
> Part 2 using one of my favorite facts from
> graphics engineering: lets say you have an
> enclosed shape, and you want to color every
> pixel inside of it. How do you know if a given
> pixel is inside the shape or not? Well, it
> turns out: if you shoot a ray in any direction
> from the pixel and it crosses the boundary an
> _odd number_ of times, it's _inside_. if it crosses
> an even number of times, it's outside. Works
> for all enclosed shapes, even self-intersecting
> and non-convex ones.
Anders Englöf Ytterström
b681e5cdb7