行为树 bTickIntervals

最新推荐文章于 2022-02-07 10:15:32 发布

原创最新推荐文章于 2022-02-07 10:15:32 发布 · 459 阅读

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本文探讨了游戏开发中行为树的一个辅助节点UBTAuxiliaryNode的实现逻辑，特别是其WrappedTickNode方法如何根据设置来调整滴答行为，并管理节点内存以实现周期性的节点执行。

/** 如果设置，条件滴答将使用剩余时间形成节点的内存 */
uint8 bTickIntervals：1；

//BTAuxiliaryNode.h
UCLASS(Abstract)
class AIMODULE_API UBTAuxiliaryNode : public UBTNode
{
	/** if set, conditional tick will use remaining time form node's memory */
	uint8 bTickIntervals : 1;

逻辑待看

bool UBTAuxiliaryNode::WrappedTickNode(UBehaviorTreeComponent& OwnerComp, uint8* NodeMemory, float DeltaSeconds, float& NextNeededDeltaTime) const
{
	if (bNotifyTick || HasInstance())
	{
		const UBTAuxiliaryNode* NodeOb = HasInstance() ? static_cast<UBTAuxiliaryNode*>(GetNodeInstance(OwnerComp, NodeMemory)) : this;
		
		ensure(NodeOb);

		if (NodeOb != nullptr && NodeOb->bNotifyTick)
		{
			float UseDeltaTime = DeltaSeconds;

			if (NodeOb->bTickIntervals)
			{
				FBTAuxiliaryMemory* AuxMemory = GetSpecialNodeMemory<FBTAuxiliaryMemory>(NodeMemory);
				AuxMemory->NextTickRemainingTime -= DeltaSeconds;
				AuxMemory->AccumulatedDeltaTime += DeltaSeconds;

				const bool bTick = AuxMemory->NextTickRemainingTime <= 0.0f;
				if (bTick)
				{
				    UseDeltaTime = AuxMemory->AccumulatedDeltaTime;
				    AuxMemory->AccumulatedDeltaTime = 0.0f;
    
				    const_cast<UBTAuxiliaryNode*>(NodeOb)->TickNode(OwnerComp, NodeMemory, UseDeltaTime);
				}

				if (AuxMemory->NextTickRemainingTime < NextNeededDeltaTime)
				{
					NextNeededDeltaTime = AuxMemory->NextTickRemainingTime;
				}
				return bTick;
			}
			else
			{
				const_cast<UBTAuxiliaryNode*>(NodeOb)->TickNode(OwnerComp, NodeMemory, UseDeltaTime);
				NextNeededDeltaTime = 0.0f;
				return true;
			}

		}
	}
	return false;
}