Recast Graphs causing very unrealistic paths?

Beginner Questions
#1

Hi, I’m trying to do a world where the player can place structures. To do this I thought I’d try Recast in the Pro version to allow this.

I made a very simple scene and added the A* script, set it to recast. I added a Seeker and started playing with various settings.

By default I get this path: http://i.imgur.com/2CiRpyB.png - Which is all over the place and not really desired…

I tried adding Smoothing: http://i.imgur.com/mdWKpCY.png - Which is better but still massively inefficient.

The only way I can make it look good is to really mess with the smoothing - so much so that it just goes through unwalkable areas by a mile.

Am I missing something really obvious here? Why is it only pathing to the centre of a triangle - surely it can use anywhere within the area as a guide point?

#2

Though I’ve just realised the Funnel Modifier makes the paths exactly as I expect.

Can I get a run down of what Funnel does and is it Expensive?

#3

Yup. The funnel modifier is the one that you should use.

The funnel modifier is not that expensive. For very long paths it can be, but usually it is fine.
Here is a detailed description (not written by me) of how the funnel algorithm works: http://digestingduck.blogspot.se/2010/03/simple-stupid-funnel-algorithm.html Essentially it finds the shortest path within the corridor formed by the triangle nodes that the path traversed.