创建如图所示的对象结构,parent为空对象，然后将下面的代码挂载到parent对象上运行即可。

 1 using UnityEngine;
 2 using System.Collections;
 3 
 4 public class CombineMeshAndMaterials : MonoBehaviour
 5 {
 6     void Start()
 7     {
 8         CombineMesh();
 9     }
10     void CombineMesh()
11     {
12         //收集要合并的贴图
13         MeshRenderer[] oldMRArray = GetComponentsInChildren<MeshRenderer>();
14         Material[] oldMArray = new Material[oldMRArray.Length];
15         Texture2D[] textures = new Texture2D[oldMRArray.Length];
16         for (int i = 0, iMax = oldMRArray.Length; i < iMax; ++i)
17         {
18             oldMArray[i] = oldMRArray[i].sharedMaterial;
19             Texture2D t2d = oldMArray[i].GetTexture("_MainTex") as Texture2D;
20             Texture2D _t2d = new Texture2D(t2d.width, t2d.height, TextureFormat.ARGB32, false);
21             _t2d.SetPixels(t2d.GetPixels(0, 0, t2d.width, t2d.height));
22             _t2d.Apply();
23             textures[i] = _t2d;
24         }
25 
26         //创建合并后的材质
27         MeshRenderer newMR = gameObject.AddComponent<MeshRenderer>();
28         Material newM = new Material(oldMArray[0].shader);
29         newM.CopyPropertiesFromMaterial(oldMArray[0]);
30         newMR.sharedMaterial = newM;
31 
32         //创建合并后的贴图，
33         Texture2D newTex = new Texture2D(1024, 1024);
34         newM.SetTexture("_MainTex", newTex);   //将合并后的贴图赋给合并后的材质
35 
36         //重新计算题图UV
37         MeshFilter[] oldMF = GetComponentsInChildren<MeshFilter>();
38         CombineInstance[] combines = new CombineInstance[oldMF.Length];
39         Rect[] rects = newTex.PackTextures(textures, 10, 1024);  //贴图打包 ，矩形的数组包含每个输入的纹理的UV坐标
40         for (int i = 0, iMax = oldMF.Length; i < iMax; ++i)
41         {
42             Rect rect = rects[i];
43             Mesh mesh = oldMF[i].mesh;
44             Vector2[] newUVs = new Vector2[mesh.uv.Length];
45 
46             //刷新uv
47             for (int j = 0, jMax = mesh.uv.Length; j < jMax; ++j)
48             {
49                 //如果这里看不太懂，说明对uv的确切含义不太明白
50                 //uv是一个比值,u = 横向第u个像素/原始贴图的宽度    v = 竖向第v个像素/原始贴图的高度
51                 //rect.x : 原贴图在合并后的贴图的 x 坐标，  rect.y : 原贴图在合并后的贴图的 y 坐标
52                 newUVs[j].x = mesh.uv[j].x * rect.width + rect.x;
53                 newUVs[j].y = mesh.uv[j].y * rect.height + rect.y;
54             }
55             mesh.uv = newUVs;
56             combines[i].mesh = mesh;
57             combines[i].transform = oldMF[i].transform.localToWorldMatrix;  //没有这句,合并后的网格无法看到
58             oldMF[i].gameObject.SetActive(false);
59         }
60 
61         //创建合并后的网格
62         MeshFilter newMF = gameObject.AddComponent<MeshFilter>();
63         Mesh newMesh = new Mesh();
64         newMesh.CombineMeshes(combines, true, true);
65         newMF.mesh = newMesh;
66     }
67 }