Unity3D网格功能生成球体网格模型
时间：2020-11-20 18:18:44 | 栏目：.NET代码 | 点击：次
本文实例为大家分享了Unity3D网格功能生成球体网格模型的具体代码，供大家参考，具体内容如下
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;
}
}