使用Unity3D的网格功能生成自己的球体网格模型

        前面已经讲过怎样使用mesh生成一个自己的网格，那么本文将会讲述怎样将这个网格变换成自己想要的形状，比如一个球体。

我们需要知道一个从平面坐标到球体坐标的映射公式。假设平面坐标是（x，y），球体坐标是（x₀，y₀，z₀），则

        球体坐标（x₀，y₀，z₀）可以通过以下代码得到，（x，y） 对应vertices[i].x和vertices[i].y。

            v.x = r * Mathf.Cos(vertices[i].x / width * 2 * Mathf.PI) * Mathf.Cos(vertices[i].y / height * Mathf.PI - Mathf.PI / 2);v.y = r * Mathf.Sin(vertices[i].x / width * 2 * Mathf.PI) * Mathf.Cos(vertices[i].y / height * Mathf.PI - Mathf.PI / 2);v.z = r * Mathf.Sin(vertices[i].y / height * Mathf.PI - Mathf.PI / 2);

           完整代码在最后，将完整的脚本绑定到一个空物体上，把棋盘格图案chessboard.jpg放到Assets\Resources下，还要在场景中生成一个sphere作为显示网格顶点的辅助物体。一切就绪后，运行效果如下：

using UnityEngine;
using System.Collections;public class BallMesh : MonoBehaviour
{Mesh mesh;Vector3[] vertices;Vector2[] uv;int[] triangles;Vector3[] normals;public GameObject sphere;GameObject[] spheres;void Start(){gameObject.AddComponent<MeshFilter>();gameObject.AddComponent<MeshRenderer>();Texture img = (Texture)Resources.Load("tm");gameObject.GetComponent<Renderer>().material.mainTexture = img;mesh = new Mesh();int m = 25; //row  int n = 50;  //col  float width = 8;float height = 6;vertices = new Vector3[(m + 1) * (n + 1)];//the positions of vertices  spheres = new GameObject[(m + 1) * (n + 1)];uv = new Vector2[(m + 1) * (n + 1)];normals = new Vector3[(m + 1) * (n + 1)];triangles = new int[6 * m * n];for (int i = 0; i < vertices.Length; i++){float x = i % (n + 1);float y = i / (n + 1);float x_pos = x / n * width;float y_pos = y / m * height;vertices[i] = new Vector3(x_pos, y_pos, 0);float u = x / n;float v = y / m;uv[i] = new Vector2(u, v);}for (int i = 0; i < 2 * m * n; i++){int[] triIndex = new int[3];if (i % 2 == 0){triIndex[0] = i / 2 + i / (2 * n);triIndex[1] = triIndex[0] + 1;triIndex[2] = triIndex[0] + (n + 1);}else{triIndex[0] = (i + 1) / 2 + i / (2 * n);triIndex[1] = triIndex[0] + (n + 1);triIndex[2] = triIndex[1] - 1;}triangles[i * 3] = triIndex[0];triangles[i * 3 + 1] = triIndex[1];triangles[i * 3 + 2] = triIndex[2];}int r = 10;for (int i = 0; i < vertices.Length; i++){spheres[i] =  Instantiate( sphere,this.transform) as GameObject;Vector3 v ;v.x = r * Mathf.Cos(vertices[i].x / width * 2 * Mathf.PI) * Mathf.Cos(vertices[i].y / height * Mathf.PI - Mathf.PI / 2);v.y = r * Mathf.Sin(vertices[i].x / width * 2 * Mathf.PI) * Mathf.Cos(vertices[i].y / height * Mathf.PI - Mathf.PI / 2);v.z = r * Mathf.Sin(vertices[i].y / height * Mathf.PI - Mathf.PI / 2);//v = vertices[i];vertices[i] = v;spheres[i].transform.localPosition = v;normals[i] = new Vector3(0,1,0);}mesh.vertices = vertices;mesh.normals = normals;mesh.uv = uv;mesh.triangles = triangles;this.GetComponent<MeshFilter>().mesh = mesh;}}