unity 实时更新动态路径mesh

如果你需要在运行时实时更新动态路径的Mesh，可以在上一个示例中稍作修改。具体来说，你需要在Update方法中更新Mesh的顶点和法线，并调用Mesh的RecalculateTangents方法重新计算切线。

下面是修改后的示例代码：

using UnityEngine;

public class DynamicPathMesh : MonoBehaviour
{
    public Transform[] pathPoints;  // 路径点

    private MeshFilter meshFilter;
    private MeshRenderer meshRenderer;
    private Mesh mesh;

    void Start()
    {
        // 获取Mesh组件
        meshFilter = GetComponent<MeshFilter>();
        meshRenderer = GetComponent<MeshRenderer>();

        // 创建Mesh
        mesh = new Mesh();
        mesh.name = "PathMesh";

        // 初始化Mesh的顶点和索引
        Vector3[] vertices = new Vector3[pathPoints.Length];
        int[] indices = new int[(pathPoints.Length - 1) * 6];
        for (int i = 0; i < pathPoints.Length; i++)
        {
            vertices[i] = pathPoints[i].position;
            if (i > 0)
            {
                int j = (i - 1) * 6;
                indices[j] = i - 1;
                indices[j + 1] = i;
                indices[j + 2] = i - 1 + pathPoints.Length;
                indices[j + 3] = i - 1 + pathPoints.Length;
                indices[j + 4] = i;
                indices[j + 5] = i + pathPoints.Length;
            }
        }
        mesh.vertices = vertices;
        mesh.triangles = indices;

        // 计算法线和切线
        mesh.RecalculateNormals();
        mesh.RecalculateTangents();

        // 将Mesh赋值给组件
        meshFilter.mesh = mesh;
        meshRenderer.enabled = true;
    }

    void Update()
    {
        // 更新Mesh的顶点和法线
        Vector3[] vertices = mesh.vertices;
        for (int i = 0; i < pathPoints.Length; i++)
        {
            vertices[i] = pathPoints[i].position;
        }
        mesh.vertices = vertices;
        mesh.RecalculateNormals();

        // 重新计算切线
        mesh.RecalculateTangents();
    }
}

这个脚本将根据传入的路径点实时更新路径的Mesh，并将其赋值给物体的Mesh Filter组件。你可以将这个脚本挂载到一个物体上，然后设置路径点即可。