Cheers guys
I now have my A star based pathways routine up and running and, with a few test waypoint trails have tested, I have NPCs choosing realistic combinations of pathways across the terrain when moving between areas of the map.
The intention is, under peaceful conditions, they will always use these pathways but if attacked will then use the full nav mesh to enable 'off pathway' navigation through the rest of the terrain ... like running off into woods etc.
Here comes the interesting bit, determining where to paint the pathways in the more mountainous areas will be done by observing the random motion of a 100 or so NPCs through the level and identifying natural routes through the topography that are highlighted by the nav mesh based path finding.
Once these identified pathways are painted on the terrain, and extended to the key locations on the map, 'path waypoints' will be placed along them and used to feed into the pathway solver.
Thus, when moving from A to B, I determine the closest pathway waypoint to both the start and end positions and use the solver to determine an optimal list of path waypoints between them.
This ensures the NPCs initially join the closest pathway and then follow the pathways till they reach the closest point to their destination, breaking off at that point and navigating using the nav mesh to their final destination.
This should will give the appearance of NPCs being aware of natural paths through their environment and choosing these to travel between differing locations without having to hard code routes between destinations.
These waypoint based pathways will only be used in open countryside. Populated areas will simply use nav mesh navigation as that's generally more appropriate in built up or densely populated areas.
