Got it so the character cannot move on some areas in a specific case.
Extracted the simple nav mesh system to it's own class.
Implemented a Point-In-Polygon algorithm.
Made it so you don't need the lastr coord to repeat in the Point-In-Polygon test.
Added a simple inspector script for Polygon.cs
The navigation mesh is now found by searching for a GO tagged with NavigationMesh. This should stop the game from crashing when there isn't a navigation mesh linked to the charact controller script.
NavMesh Dummy mesh will now allow you to click anywhere.