有关这个问题，获取主角面前的箱子或者敌人对象，我在网上看到雨松写的一段代码，把它贴在下面

using UnityEngine;
using System.Collections;
 
public class MyTest : MonoBehaviour {
 
	public Transform cube;
 
	private float distance = 5f;
	void Update () 
	{
		Quaternion r= transform.rotation;
		Vector3 f0 =  (transform.position  + (r *Vector3.forward) * distance);
		Debug.DrawLine(transform.position,f0,Color.red);
 
		Quaternion r0= Quaternion.Euler(transform.rotation.eulerAngles.x,transform.rotation.eulerAngles.y - 30f,transform.rotation.eulerAngles.z);
		Quaternion r1= Quaternion.Euler(transform.rotation.eulerAngles.x,transform.rotation.eulerAngles.y + 30f,transform.rotation.eulerAngles.z);
 
		Vector3 f1 =  (transform.position  + (r0 *Vector3.forward) * distance);
		Vector3 f2 =  (transform.position  + (r1 *Vector3.forward) * distance);
 
		Debug.DrawLine(transform.position,f1,Color.red);
		Debug.DrawLine(transform.position,f2,Color.red);
 
		Debug.DrawLine(f0,f1,Color.red);
		Debug.DrawLine(f0,f2,Color.red);
 
		Vector3 point = cube.position;
 
		if(isINTriangle(point,transform.position,f1,f0) || isINTriangle(point,transform.position,f2,f0) )
		{
			Debug.Log("cube in this !!!");
		}else 
		{
			Debug.Log("cube not in this !!!");
		}
 
	}
 
	private  float triangleArea(float v0x,float v0y,float v1x,float v1y,float v2x,float v2y) 
	{
        return Mathf.Abs((v0x * v1y + v1x * v2y + v2x * v0y
            - v1x * v0y - v2x * v1y - v0x * v2y) / 2f);
    }
 
	bool isINTriangle(Vector3 point,Vector3 v0,Vector3 v1,Vector3 v2)
	{
		float x = point.x;
		float y = point.z;
 
		float v0x = v0.x;
		float v0y = v0.z;
 
		float v1x = v1.x;
		float v1y = v1.z;
 
		float v2x = v2.x;
		float v2y = v2.z;
 
		float t = triangleArea(v0x,v0y,v1x,v1y,v2x,v2y);
		float a = triangleArea(v0x,v0y,v1x,v1y,x,y) + triangleArea(v0x,v0y,x,y,v2x,v2y) + triangleArea(x,y,v1x,v1y,v2x,v2y);
 
		if (Mathf.Abs(t - a) <= 0.01f) 
		{
			return true;
		}else 
		{
			return false;
		}
	}
}

然后我自己认为的是 先求出主角附近5米范围内的所有物体，相当于规定一个圆的范围，再获取主角与箱子之间的角度或者点乘来判断是否在主角的视角内，这样不是简单一点吗，鱼松的用了好多向量的运算和角度的计算，下面我贴一下我的代码，是lua写的

-- 得到角色附近 面前的物品
function GetInSightBoxes(hero)
	local newBoxes = {}
	local pos = hero:GetPosition()	
	local cameraController = hero.cameraController
	local lookForward = cameraController.cameraTrans.forward
	--local forward  = cameraController.cameraTrans:TransformDirection(Vector3.forward)
	for uid, box in pairs(Boxes) do
		local dist = Vector3.Distance(Vector3(box.position.x, 0, box.position.z), Vector3(pos.x, 0, pos.z))
		if dist < 5 then
			box.distance = dist
			local toOther = Vector3(box.position.x, 0, box.position.z) - Vector3(pos.x, 0, pos.z)
			local angle = Vector3.Angle(toOther, lookForward)
		    if angle < 45 then
			    newBoxes[uid] = box
		    end
			print("angle=========================="..angle)
			
			--local dot = Vector3.Dot(forward, toOther)
		end
	end
	return newBoxes
end

我这样写是否存在什么劣势，这种情况一般是怎么处理