Comment by larkeith

7 years ago

The only relevant points are those that make up the coastlines - there is no need to test paths that start and/or end in the middle of sea or land.

Oh I see what you mean. Yes, I suppose it is worded that way to impress the reader with the big numbers involved, when many of them can be trivially rejected.

Coastlines are close to infinite in length (they grow inversely to the length of the measure used; idealised mathematical 'coastlines' are fractal and infinite), we can limit them by limiting the resolution.