Debugging the Nav Mesh Agent

The Nav Mesh Agent component of the guards will use Unity navigation system to reach a given target point.

Generating Off Mesh Link will ensure that AI will be able to climb or jump down a ladder or height, the Areas and the costs will establish which one of the possible paths is the best to reach a given target point:

In this image, the guard has a series of choices to evaluate to reach the point

It is important to properly set the quality and the priority of the Agent, but even more important is the radius and the height, which determines the actual size of the Nav Mesh Agent in the world. These settings must reflect the settings you have chosen in the NavMesh bake settings, otherwise there might be spots where a path is narrower than the radius of the Nav Mesh Agent itself which will make it impossible to pass through.

To debug the AI Nav Mesh Agent properly, we will run the scene in the editor and watch the Scene view instead of the Game window.

Show the Navigation window, then choose one of the guard_aai-final prefabs we have prepared in the Hierarchy. Now, press Play and then switch back to the Scene view to see what the AI actually is doing, like in the following screenshot:

Selecting an AI GameObject in the Hierarchy and with the Navigation window open you will see more data in the Scene view

In Chapter 13, Optimization and Final Touches, we will place a dozen guards around the island at specific spots and create predefined routes made of custom waypoints for them to follow to make the game more interesting.