https://www.cnblogs.com/eangulee/p/3877824.html
unity 3d 之合并网格和贴图(combine mesh and texture)
本人是个小白，但是有个做技术的理想。
关于合并网格和贴图这个问题困扰了我好久，问群友，逛论坛，翻帖子，或者说是我的愚笨吧，不过经过努力还是我解决了，测试通过，一个8drawcall的模型，合并后降到2drawcall，当然现在移动设备的性能都比较高了，不必过多纠结于drawcall，如果没这需要请路过吧。。。
好的，废话不多说，我把代码贴出来。
1 using UnityEngine;
2 using System.Collections;
3 using System.Collections.Generic;
4 using System.IO;
5
6 public class CombineMesher : MonoBehaviour
7 {
8 // Use this for initialization
9 void Start()
10 {
11 Combine(transform);
12 }
13
14 // Update is called once per frame
15 void Update()
16 {
17
18 }
19
20
21 public Transform Combine(Transform root)
22 {
23 float startTime = Time.realtimeSinceStartup;
24
25 // The SkinnedMeshRenderers that will make up a character will be
26 // combined into one SkinnedMeshRenderers using one material.
27 // This will speed up rendering the resulting character.
28 // note:each SkinnedMeshRenderer must share a same material
29 List<CombineInstance> combineInstances = new List<CombineInstance>();
30 List<Material> materials = new List<Material>();
31 Material material = null;
32 List<Transform> bones = new List<Transform>();
33 Transform[] transforms = root.GetComponentsInChildren<Transform>();
34 List<Texture2D> textures = new List<Texture2D>();
35 int width = 0;
36 int height = 0;
37
38 int uvCount = 0;
39
40 List<Vector2[]> uvList = new List<Vector2[]>();
41
42 foreach (SkinnedMeshRenderer smr in root.GetComponentsInChildren<SkinnedMeshRenderer>())
43 {
44 if (material == null)
45 material = Instantiate(smr.sharedMaterial) as Material;
46 for (int sub = 0; sub < smr.sharedMesh.subMeshCount; sub++)
47 {
48 CombineInstance ci = new CombineInstance();
49 ci.mesh = smr.sharedMesh;
50 ci.subMeshIndex = sub;
51 combineInstances.Add(ci);
52 }
53
54 uvList.Add(smr.sharedMesh.uv);
55 uvCount += smr.sharedMesh.uv.Length;
56
57 if (smr.material.mainTexture != null)
58 {
59 textures.Add(smr.renderer.material.mainTexture as Texture2D);
60 width += smr.renderer.material.mainTexture.width;
61 height += smr.renderer.material.mainTexture.height;
62 }
63
64 // we need to recollect references to the bones we are using
65 foreach (Transform bone in smr.bones)
66 {
67 foreach (Transform transform in transforms)
68 {
69 if (transform.name != bone.name) continue;
70 bones.Add(transform);
71 break;
72 }
73 }
74 Object.Destroy(smr.gameObject);
75 }
76
77 // Obtain and configure the SkinnedMeshRenderer attached to
78 // the character base.
79 SkinnedMeshRenderer r = root.gameObject.GetComponent<SkinnedMeshRenderer>();
80 if (!r)
81 r = root.gameObject.AddComponent<SkinnedMeshRenderer>();
82
83 r.sharedMesh = new Mesh();
84
85 //only set mergeSubMeshes true will combine meshs into single submesh
86 r.sharedMesh.CombineMeshes(combineInstances.ToArray(), true, false);
87 r.bones = bones.ToArray();
88 r.material = material;
89
90 Texture2D skinnedMeshAtlas = new Texture2D(1024, 512);
91 Rect[] packingResult = skinnedMeshAtlas.PackTextures(textures.ToArray(), 0);
92 Vector2[] atlasUVs = new Vector2[uvCount];
93
94 //as combine textures into single texture,so need recalculate uvs
95
96 int j = 0;
97 for (int i = 0; i < uvList.Count; i++)
98 {
99 foreach (Vector2 uv in uvList[i])
100 {
101 atlasUVs[j].x = Mathf.Lerp(packingResult[i].xMin, packingResult[i].xMax, uv.x);
102 atlasUVs[j].y = Mathf.Lerp(packingResult[i].yMin, packingResult[i].yMax, uv.y);
103 j++;
104 }
105 }
106
107 r.material.mainTexture = skinnedMeshAtlas;
108 r.sharedMesh.uv = atlasUVs;
109
110 Debug.Log("combine meshes takes : " + (Time.realtimeSinceStartup - startTime) * 1000 + " ms");
111 return root;
112 }
113 }
本人是个小白，但是有个做技术的理想。
关于合并网格和贴图这个问题困扰了我好久，问群友，逛论坛，翻帖子，或者说是我的愚笨吧，不过经过努力还是我解决了，测试通过，一个8drawcall的模型，合并后降到2drawcall，当然现在移动设备的性能都比较高了，不必过多纠结于drawcall，如果没这需要请路过吧。。。
好的，废话不多说，我把代码贴出来。
1 using UnityEngine;
2 using System.Collections;
3 using System.Collections.Generic;
4 using System.IO;
5
6 public class CombineMesher : MonoBehaviour
7 {
8 // Use this for initialization
9 void Start()
10 {
11 Combine(transform);
12 }
13
14 // Update is called once per frame
15 void Update()
16 {
17
18 }
19
20
21 public Transform Combine(Transform root)
22 {
23 float startTime = Time.realtimeSinceStartup;
24
25 // The SkinnedMeshRenderers that will make up a character will be
26 // combined into one SkinnedMeshRenderers using one material.
27 // This will speed up rendering the resulting character.
28 // note:each SkinnedMeshRenderer must share a same material
29 List<CombineInstance> combineInstances = new List<CombineInstance>();
30 List<Material> materials = new List<Material>();
31 Material material = null;
32 List<Transform> bones = new List<Transform>();
33 Transform[] transforms = root.GetComponentsInChildren<Transform>();
34 List<Texture2D> textures = new List<Texture2D>();
35 int width = 0;
36 int height = 0;
37
38 int uvCount = 0;
39
40 List<Vector2[]> uvList = new List<Vector2[]>();
41
42 foreach (SkinnedMeshRenderer smr in root.GetComponentsInChildren<SkinnedMeshRenderer>())
43 {
44 if (material == null)
45 material = Instantiate(smr.sharedMaterial) as Material;
46 for (int sub = 0; sub < smr.sharedMesh.subMeshCount; sub++)
47 {
48 CombineInstance ci = new CombineInstance();
49 ci.mesh = smr.sharedMesh;
50 ci.subMeshIndex = sub;
51 combineInstances.Add(ci);
52 }
53
54 uvList.Add(smr.sharedMesh.uv);
55 uvCount += smr.sharedMesh.uv.Length;
56
57 if (smr.material.mainTexture != null)
58 {
59 textures.Add(smr.renderer.material.mainTexture as Texture2D);
60 width += smr.renderer.material.mainTexture.width;
61 height += smr.renderer.material.mainTexture.height;
62 }
63
64 // we need to recollect references to the bones we are using
65 foreach (Transform bone in smr.bones)
66 {
67 foreach (Transform transform in transforms)
68 {
69 if (transform.name != bone.name) continue;
70 bones.Add(transform);
71 break;
72 }
73 }
74 Object.Destroy(smr.gameObject);
75 }
76
77 // Obtain and configure the SkinnedMeshRenderer attached to
78 // the character base.
79 SkinnedMeshRenderer r = root.gameObject.GetComponent<SkinnedMeshRenderer>();
80 if (!r)
81 r = root.gameObject.AddComponent<SkinnedMeshRenderer>();
82
83 r.sharedMesh = new Mesh();
84
85 //only set mergeSubMeshes true will combine meshs into single submesh
86 r.sharedMesh.CombineMeshes(combineInstances.ToArray(), true, false);
87 r.bones = bones.ToArray();
88 r.material = material;
89
90 Texture2D skinnedMeshAtlas = new Texture2D(1024, 512);
91 Rect[] packingResult = skinnedMeshAtlas.PackTextures(textures.ToArray(), 0);
92 Vector2[] atlasUVs = new Vector2[uvCount];
93
94 //as combine textures into single texture,so need recalculate uvs
95
96 int j = 0;
97 for (int i = 0; i < uvList.Count; i++)
98 {
99 foreach (Vector2 uv in uvList[i])
100 {
101 atlasUVs[j].x = Mathf.Lerp(packingResult[i].xMin, packingResult[i].xMax, uv.x);
102 atlasUVs[j].y = Mathf.Lerp(packingResult[i].yMin, packingResult[i].yMax, uv.y);
103 j++;
104 }
105 }
106
107 r.material.mainTexture = skinnedMeshAtlas;
108 r.sharedMesh.uv = atlasUVs;
109
110 Debug.Log("combine meshes takes : " + (Time.realtimeSinceStartup - startTime) * 1000 + " ms");
111 return root;
112 }
113 }