I am doing a unreal engine project, and i am trying to get the enemy to patrol between different spots (target points). When I ran the project to make sure it had no errors, I got something but i don’t know how to solve it.
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Hello Spencer3,
From what I see, that error is saying that when it runs the “Get Blackboard” function, it’s being given a null value which means that the blackboard isn’t set on “Self”, which would be the blueprint that this script is contained in. Can you check to see if the blackboard is set? You can set up a “Is Valid” node with a “Branch” node to avoid this if you plan to set the Blackboard at runtime.
how can I see if the blackboard is set? and how can I set it?
Assuming that Enemy is a Behavior Tree asset, you should be able to see/set it in the Details tab for the Behavior Tree under “Blackboard Asset”.
I went into the behavior tree, and I set the blackboard asset, but when I ran it, I got the same error. How can I make sure that the enemy is a behavior tree asset?
The enemy doesn’t need to be a behavior tree asset. I didn’t think about this before, but is Enemy a pawn or your controller? If Enemy is your pawn class, then you’ll need to get a reference to the AI Controller for that point and then get the Blackboard of that AI Controller. The reason it would be returning null is because the pawn itself doesn’t store the blackboard.