Pathfinding problem

[uservsParticipant]

Hello. I am testing a pathfinding. And in some cases solution can not be found. Unit uses BasicMotor without Face Target. It goes to static navigation target. In specific case (screen #1) navigator can not build the path (why?). But when the unit was shifted to the left (screen #2) then the navigator was able to build the path.

[uservsParticipant]

Another case.

[uservsParticipant]

Mesh parameters:

AI parameters:

[uservsParticipant]

I changed the Cell Size to 0.2 and it worked.

[CodersExpoParticipant]

This is awesome. Thanks for the detailed feedback. I know this will help others.

NOTE ON CELL SIZE: “The resolution of the Navigation Mesh in meters. The higher this value the more accurate the mesh is at small sizes, but the more memory and time it will take to generate. The resolution of your mesh can be calculated by the following equation: size * localScale.x * cellSize * size * localScale.z * cellSize.”

Another thing to consider, often times people will find when they select the navigation mesh they will see the character standing in an unmasked section where the navigation mesh didn’t cover, especially on rough terrain. It’s a good idea to mess with cell size and step height in these cases.

Glad to see you were able to work it out!

[uservsParticipant]

Thanks for the reply. But I don’t understand why your LPA was failed at this situation. May be it’s a bug in pathfinding algorithm?

[uservsParticipant]

It generates a more rough mesh with greater values of cell size.

[CodersExpoParticipant]

It’s a good question Uservs. I don’t know. I would suggest emailing Jester for a more specific answer. I do know that it works (for me) to tweak cell settings to get better behavior.

[uservsParticipant]

Based on the formula it is possible to increase the resolution of the mesh size or increasing the local scale without changing the size of the cell. I increased the size of the mesh leaving the cell size equal 0,1. Possible solution but not obvious.

• This reply was modified 9 months ago by  uservs.

[uservsParticipant]

I have a next problem. The unit is outside walkable area. It walks to target and stucks for unknown reason. In this case navigator cannot build the path.

• This reply was modified 9 months ago by  uservs.

[uservsParticipant]

It is probably a colliders radius tweaks. But is it possible to restore from this state? For example unit was dropped to unwalkable area. Can unit detect a nearest valid point and go to it?

• This reply was modified 9 months ago by  uservs.

[CodersExpoParticipant]

If you fall off the navigation grid….hmmmm, I believe you would have to do a little work to get the character back on. Path finding and movement would likely fail.

You could search for the nearest point, like what you may have seen in the waypath network tutorials, but will then probably have to use Unity’s MoveTowards (http://docs.unity3d.com/ScriptReference/Vector3.MoveTowards.html) target and then allow RAIN navigator to take over again.

I know there was some discussion on this forum for support of off mesh linking but not sure when that will be implemented or if it would help in this case, though it seems to me that it could.

[uservsParticipant]

Some solution is to reset option Valid Path Required.

[CodersExpoParticipant]

Ah..did that work for you? If so that’s a great tip. Thanks uservs

[uservsParticipant]

Yes, it works for me. May be a custom motor with raycasting is not a bad variant for this task.

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