Unity3D生成一段隧道网格的方法

本文实例为大家分享了Unity3D生成一段隧道网格的具体代码，供大家参考，具体内容如下

一、需求

最近有一个需求，生成段隧道的骨架网格。目前想到的方法就是，获取隧道网格，通过一个算法分离内框和外框的点：

然后通过外框和内框上的点画线，可以通过深度优先搜索得到内外两个环的序列， 从而实现骨架网格

二、生成隧道算法

隧道由段圆弧和一条直线组成，所以算法如下：

1、取圆心为0，0，0，和圆上半径的向量 \underset{OB}{\rightarrow}  ，绕z轴，旋转向量\underset{OB}{\rightarrow}，取到圆上的点，外框上的点同理可得

2、平移内外框上的点，z轴加上偏离，得到隧道另一端的点

3、取相邻外框上的点和平移后的四个点，生成两个三角形。内框同理可得。

三、效果如下：

四、实现：

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

public class MeshCreater : MonoBehaviour
{
Mesh mesh;
public Material mat;//mesh材质
public GameObject game;

// Start is called before the first frame update
void Start()
{
mesh = new Mesh();
mesh.Clear();
SetVertivesUV();
SetTriangles();
mesh.vertices = vertices.ToArray();
mesh.triangles = triangles;
GameObject obj_cell = new GameObject();
obj_cell.name = "cell";

mesh.RecalculateNormals();//重置法线

mesh.RecalculateBounds(); //重置范围

obj_cell.AddComponent<MeshFilter>().mesh = mesh;
obj_cell.AddComponent<MeshRenderer>();
obj_cell.GetComponent<MeshRenderer>().material = mat;

MeshCaluate mesh_caluate = new MeshCaluate();
mesh_caluate.CalculateMesh(mesh);
}

// Update is called once per frame
void Update()
{

}

public List<Vector3> vertices = new List<Vector3>();

private float angle = 10;

private float max_angle = 120;
// 设置顶点信息
void SetVertivesUV()
{
Vector3 dir1 = new Vector3(Mathf.Sqrt(3f), -1, 0);
Vector3 dir2 = dir1 * 0.8f;

List<Vector3> points1 = new List<Vector3>();
List<Vector3> points2 = new List<Vector3>();

int count = (int)((360 - max_angle) / angle);

for (int i = 0; i < count; i++)
{
 Quaternion q= Quaternion.AngleAxis(i * angle, Vector3.forward);

Vector3 point1 = q* dir1;
 Vector3 point2 = q* dir2;
 points1.Add(point1);
 points2.Add(point2);
}
points1.Add(points1[0]);
points2.Add(points2[0]);

for (int i = 0; i < points1.Count; i++)
{
 var v1 = points1[i];
 var v2 = points2[i];
 var v3 = points1[i];
 v3.z = 10;
 var v4 = points2[i];
 v4.z = 10;

vertices.Add(v1);
 vertices.Add(v3);
 vertices.Add(v2);
 vertices.Add(v4);
}
}

private int[] triangles;//索引
// 设置索引
void SetTriangles()
{
triangles = new int[vertices.Count * 3];
int c = 0;
for (int i = 0; i < triangles.Length -12 ; i += 12)
{
 var v1 = c;
 var v2 = c + 1;
 var v3 = c + 4;
 var v4 = c + 5;

var v5 = c + 2;
 var v6 = c + 3;
 var v7 = c + 6;
 var v8 = c + 7;

triangles[i] = v4;
 triangles[i + 1] = v2;
 triangles[i + 2] = v1;

triangles[i + 3] = v3;
 triangles[i + 4] = v4;
 triangles[i + 5] = v1;

triangles[i + 6] = v5;
 triangles[i + 7] = v6;
 triangles[i + 8] = v8;

triangles[i + 9] = v5;
 triangles[i + 10] = v8;
 triangles[i + 11] = v7;

c += 4;
}
}
}

五、缺陷

UV未计算，所以使用贴图时有问题

来源：https://blog.csdn.net/q943520218/article/details/108031765