Character Nav Agent Radius and Height

Development Character & Animation
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1

I noticed that the default values for Agent Radius and Agent Height under Nav Agent Props in a Character blueprint are -1 and I was wondering what the significance of that was. On this documentation page:

https://docs.unrealengine.com/latest/INT/Gameplay/AI/BehaviorTreeQuickStart/4/index.html

Epic suggests that we: Set the Agent Radius to at least the Capsule’s radius, and the Agent Height to at least twice the Capsule’s “half height.”, which I have done.

In the same Movement Component section that contains the radius and height settings, however, there is a check box for Update Nav Agent with Owners Collision and the tool tip says that, if checked, the Nav Agent radius and height values will be updated with the owner’s collision capsule size.

I was wondering, therefore, if the default values of -1 represent the fact that the Collision Capsule values will be used, and that by changing (effectively overriding) these values, I am negating the ability to have the values auto update if I change the capsule size. Can anyone shed any light on this?

Dean

2

I had this exact question, 5 years later, if anybody is able to provide a response. The one update to the question is that the tutorial is now at: https://docs.unrealengine.com/en-US/Engine/AI/BehaviorTrees/QuickStart/4/index.html

Another aside that’s not especially clear is how to find documentation. This stuff is inside the NavMovement component inside of the CharacterMovement. In trying to find the docs for this class I found this: http://api.unrealengine.com/INT/BlueprintAPI/AI/Components/NavMovement/index.html but the problem there is that it seems to only reference the exposed methods within the class.

One exposed boolean is “Update Nav Agent with Owner” with a tooltip of “If set to true NavAgentProps’ radius and height will be updated with owners collision capsule size.” which seems to suggest that that it’s unnecessary to change the nav agent radius/height. Perhaps this tutorial was written before this feature was added.