行为树(Behavior Tree)简介

// 行为树(Behavior Tree)// 每个节点执行后返回 成功/失败// 行为树由4种节点构成:// (1)Composite Node//    <1>Selector Node//    <2>Sequence Node//    <3>Parallel Node// (2)Decorator Node// (3)Condition Node// (4)Action Node// 由于行为树的结构和XML文件很类似,因此用XML来动态配置行为树是一个不错的方法.

// VC2008

#include "stdafx.h"#include <list>

// 节点基类template<typename EventT>class BehaviorTreeNode{public: BehaviorTreeNode(){}; virtual ~BehaviorTreeNode(){};

public: virtual bool Behavior(const EventT& e) { return true; };};

// 策略接口class BehaviorTreeBranchStrategy{public: BehaviorTreeBranchStrategy(){}; virtual ~BehaviorTreeBranchStrategy(){}; virtual void BehaviorBegin() {}; virtual void BehaviorEnd() {}; virtual bool IsContinue() { return true; }; virtual bool GetResult() { return true; };}; // 非叶子节点template<typename EventT>class BranchNode : public BehaviorTreeNode<EventT>{public: BranchNode() : m_pStrategy(0) { }; virtual ~BranchNode() {};

public: virtual void AddNode(BehaviorTreeNode<EventT>* pAddNode) {  if(pAddNode != 0)  {   m_listChildNode.push_back(pAddNode);  } } virtual void RemoveNode(BehaviorTreeNode<EventT>* pRemoveNode) {  if(pRemoveNode != 0)  {   m_listChildNode.remove(pRemoveNode);  } }

 virtual BehaviorTreeBranchStrategy* GetStrategy() const {  return m_pStrategy; } virtual void SetStrategy(BehaviorTreeBranchStrategy* pStrategy) {  m_pStrategy = pStrategy; }

 virtual bool Behavior(const EventT& e) {  if(m_pStrategy == 0)  {   return false;  }

  m_pStrategy->BehaviorBegin();  for(std::list<BehaviorTreeNode<EventT> >::iterator it = m_listChildNode.begin();   it != m_listChildNode.end(); ++it)  {   if( !m_pStrategy->IsContinue() )   {    break;   }

   m_pStrategy->Behavior( it->Behavior(e) );    }

  m_pStrategy->BehaviorEnd();  return m_pStrategy->GetResult(); }

protected: // 子节点 std::list<BehaviorTreeNode<EventT> > m_listChildNode; // 策略 BehaviorTreeBranchStrategy* m_pStrategy;};

int _tmain(int argc, _TCHAR* argv[]){

 return 0;}