Unity-群组行为AI

1.导入乌鸦模型，自带动画（素材百度网盘http://pan.baidu.com/s/1o8C5EKq）

2.创建乌鸦模型 ,目标点，以及编写脚本，使所有乌鸦可以向同一方向移动

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class CrowAI : MonoBehaviour {
 	
	public Transform target;
	public float speed=2.0f;
	public float animRandom = 2f;
	private Animation anim;

	IEnumerable Start(){ 
		anim = GetComponentInChildren<Animation> ();
		yield return new WaitForSeconds (Random.Range(0,animRandom));
	}
	void calcForce(){
		
	}
	
	// Update is called once per frame
	void Update () {
		transform.LookAt (target.transform);
		transform.Translate(Vector3.forward*Time.deltaTime*speed);
	}
}



//发现会乌鸦在飞行时有重叠并且在目标点处原地煽动翅膀位置，方向不做任何改变。


           

群组行为的代码实现:
以下分离，队列，聚集的力，需要在u3d中自行调整，已达到效果。
using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class CrowAI : MonoBehaviour {


	public Vector3 velocity= Vector3.forward;	
	public Vector3 startVelocity;
	public  float m=1f;
	//合力
	public Vector3 sumForce= Vector3.zero;

	//分离::

	public Vector3 separtionForce=Vector3.zero;//分离的力
	public float seperationDistance=3f;//分离的距离
	public List <GameObject> seperationNeighbors=new List<GameObject>(); //有影响的物体
	public float seperationWeight=1f;

	//队列：
	public Vector3 alignmentForce=Vector3.zero;	//队列的力
	public float alignmentDistance=6.0f;//队列的距离
	public List<GameObject> alignmentNeighbors=new List<GameObject>();
	public float alignmentWeight=1f;

	//聚集:
	public Vector3 cohesionForce=Vector3.zero;
	public float cohesionWeight=1f;
	public float checkInterval=0.2f;


	public Transform target;
	public float speed=2.0f;
	public int animRandomTime = 10;
	private Animation anim; 
	void Start(){ 
		startVelocity = velocity;
		InvokeRepeating ("CalcForce", 0, checkInterval);
		anim = GetComponentInChildren<Animation> (); 
		float f=Random.Range(0,animRandomTime);
		Invoke ("PlayAnim",f);	
	}		 					
	void PlayAnim(){  
		anim.Play ();
	}
	void Init(){
	 	  sumForce= Vector3.zero;
		  separtionForce=Vector3.zero;  
	 	  alignmentForce=Vector3.zero;	 	 
	      cohesionForce=Vector3.zero; 
	}	
	//若放在update里，每帧计算过于耗费性能
	void CalcForce(){
		Init (); 
		//计算离当前物体近的物体
		seperationNeighbors.Clear ();
		Collider[] colliders= Physics.OverlapSphere (transform.position  ,seperationDistance); 
		foreach (Collider c in colliders) {
			if (c != null && c.gameObject != this.gameObject) {
				seperationNeighbors.Add (c.gameObject);
			}
		}
		//计算分离的力
		foreach (GameObject neighbor in seperationNeighbors) {
			Vector3 direction = transform.position - neighbor.transform.position;
			separtionForce += direction.normalized/direction.magnitude;//近的力大，远的力小
		}
		if (seperationNeighbors.Count > 0) {
			separtionForce *= seperationWeight;//权重
			sumForce += separtionForce; 
		}
		//计算队列的力
		alignmentNeighbors.Clear();
		Vector3 avgDir = Vector3.zero;
		colliders =Physics.OverlapSphere(transform.position,alignmentDistance);
		foreach (Collider c in colliders) {
			if (c != null && c.gameObject != this.gameObject) {
				alignmentNeighbors.Add (c.gameObject);
				avgDir += c.gameObject.transform.forward;
			}
		}
		if (alignmentNeighbors.Count > 0) {
			avgDir /= alignmentNeighbors.Count;
			alignmentForce = avgDir - transform.forward;
			alignmentForce *= alignmentWeight;
			separtionForce *= seperationWeight;//权重
			sumForce += separtionForce; 
		}






		//计算聚集的力
		Vector3 center=Vector3.zero;
		if ( alignmentNeighbors.Count>0) {
			// 由于聚集的力与队列的力范围一直，因此如果队列的内容为0 也退出方法
			foreach (GameObject c in alignmentNeighbors) {
				center += c.transform.position;
			}
			center /= alignmentNeighbors.Count ;
			Vector3	dir = center - transform.position;
			cohesionForce = (cohesionForce + dir.normalized*velocity.magnitude) * cohesionWeight;
			sumForce += cohesionForce;
		}

		//保持恒定速度
		Vector3 statusForce=startVelocity-velocity;	
		sumForce += statusForce;
	}

	
	// Update is called once per frame
	void Update () {
		Vector3 a = sumForce / m;
		velocity	+= a * Time.deltaTime;
		transform.rotation = Quaternion.LookRotation (velocity);
		transform.Translate (velocity * Time.deltaTime, Space.World);
	} 
}


效果展示：https://github.com/ycb577114589/AI