Unity网格编程（2017.3）课程（Andy老师）的模型切割案例，采用Unity自带的模型Cube\sphere等模型可以成功切割，但采用自编模型（同样的正方体）就无法成功切割，无任何反应，也不报错。自己思考了很久，都想不明白是何原因，切割功能的脚本是完全采用的Andy老师课程中的最终脚本，应该没有问题，能够兼容这种情况，而生成模型的代码应该也没有问题，想请问老师这种情况可能是什么原因造成的？

图一：Unity自带的Cube模型，能够正常切割

图二：采用脚本自己生成的正方体模型，无法切割，没有丝毫效果

生成模型的代码如下：

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

[RequireComponent(typeof(MeshFilter), typeof(MeshRenderer))]
public class model3 : MonoBehaviour
{

    private Vector3[] _vertices;
    private int[] _triangles;
    void Start()
    {
        Mesh mesh = new Mesh();

        MeshFilter filter = GetComponent<MeshFilter>();
        filter.mesh = mesh;
        mesh.name = "Mesh03";
        GenerateVextex();
        GenerateTriangle();

        mesh.vertices = _vertices;
        mesh.triangles = _triangles;

        GameObject newGo = new GameObject();
        newGo.transform.position = filter.transform.position;
        newGo.transform.rotation = filter.transform.rotation;
        //newGo.transform.rotation = _hitTrans.rotation;

        newGo.AddComponent<MeshFilter>().mesh = mesh;
        newGo.AddComponent<MeshRenderer>().material = filter.GetComponent<MeshRenderer>().material;
    }

    private void GenerateVextex()
    {
        _vertices = new Vector3[8];
        _vertices[0] = new Vector3(-0.5f, -0.5f, -0.5f);
        _vertices[1] = new Vector3(0.5f, -0.5f, -0.5f);
        _vertices[2] = new Vector3(-0.5f, -0.5f, 0.5f);
        _vertices[3] = new Vector3(0.5f, -0.5f, 0.5f);

        _vertices[4] = new Vector3(-0.5f, 0.5f, -0.5f);
        _vertices[5] = new Vector3(0.5f, 0.5f, -0.5f);
        _vertices[6] = new Vector3(-0.5f, 0.5f, 0.5f);
        _vertices[7] = new Vector3(0.5f, 0.5f, 0.5f);
    }

    private void GenerateTriangle()
    {
        _triangles = new int[36];
        //底面
        _triangles[0] = 0;
        _triangles[1] = 1;
        _triangles[2] = 2;

        _triangles[3] = 1;
        _triangles[4] = 3;
        _triangles[5] = 2;
        //前
        _triangles[6] = 0;
        _triangles[7] = 4;
        _triangles[8] = 5;

        _triangles[9] = 5;
        _triangles[10] = 1;
        _triangles[11] = 0;
        //后
        _triangles[12] = 3;
        _triangles[13] = 7;
        _triangles[14] = 6;

        _triangles[15] = 3;
        _triangles[16] = 6;
        _triangles[17] = 2;
        //左
        _triangles[18] = 6;
        _triangles[19] = 4;
        _triangles[20] = 0;

        _triangles[21] = 6;
        _triangles[22] = 0;
        _triangles[23] = 2;
        //右
        _triangles[24] = 1;
        _triangles[25] = 5;
        _triangles[26] = 7;

        _triangles[27] = 7;
        _triangles[28] = 3;
        _triangles[29] = 1;
        //上
        _triangles[30] = 6;
        _triangles[31] = 7;
        _triangles[32] = 4;

        _triangles[33] = 7;
        _triangles[34] = 5;
        _triangles[35] = 4;
    }
}

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