Prevent hovering above navmesh (but more efficient than GetNearest)

Hey Aron,

is there an efficient way to push my agent towards the node underneath it?
My mobile game has elevations such as hills and stairs.
This code produces a lot of overhead (25% of the frame), because it’s done for each character, I have around 25 of them. They just need to stay on navmesh, without any expensive Physics Raycasting.

NNInfo info = wanted_nextAi_pos,  constraint,  _nearest_pathfindNodeHint );
_nearest_pathfindNodeHint =  info.node;//update "hint" for more performance during Clamp next time.
wanted_nextAI_pos =  info.position;

Looking one of such 25 “tails” in more detail, we can see that GetNearest() takes a lot of time, even with a hint:

Currently I am using a simple ABPath.cs, perhaps there is a modifier I could attach?
Or maybe I should inherit from ABPath and override MovementUpdateInternal(). But it looks hard to change, especially that it’s using Velocity2D. How should I adjust it correctly?

Thank you!


You could possibly use unity’s new RaycastCommand to do the raycast more efficiently and multithreaded?

Grid graphs are also usually faster for finding the closest node. Though I realize it might be a bit annoying to switch to a different graph type.

You can also enable Recast Graph settings -> Nearest Node Queries In XZ Space. This is faster, but it may not work as well if you have multiple floors in your game (e.g. a multi-storey building).

One thing I did in a different game (nothing included in A* Pathfinding Project) was to use a raycast every 10 frames or something and approximate the ground using a plane. Then in the other 9 frames I would simulate a raycast against the ground plane to approximate where the ground would be.