I am trying to learn GameplayKit and am using it with SceneKit so I am using a GKAgent3d for my agent to set behaviours on. I have got behaviours working but I am trying to have the agent wander around a plane that I have representing ground but when the agent is wandering it seems to be wandering on all axis so it just ends up flying around. Is there any way to have the agent stick to the ground when it is wandering?