【UnityEditor】查看模型Mesh面数/顶点数

 去掉GUI字体的三角面数，统计到的数据与Unity面板显示一致。

   Unity默认天空盒有大约1.7k三角面，5k顶点，如果使用了天空盒，需要额外注意。

关键步骤：

• Selection.selectionChanged：编辑器下当前选中的Gameobject发生变化的回调
• Selection.gameObjects：编辑器下当前选中的Gameobject
• 获取所有网格数据：
  • Gameobject.GetComponentsInChildren()：获取自身节点及所有嵌套下属节点的MeshFilter组件
  • Gameobject.GetComponentsInChildren()：获取自身节点及所有嵌套下属节点的SkinnedMeshRenderer组件
• 统计网格数据：
  • MeshFilter.sharedMesh.triangles.Length（MeshFilter三角面数）
  • MeshFilter.sharedMesh.vertexCount（MeshFilter顶点数）
  • SkinnedMeshRenderer.sharedMesh.triangles.Length（SkinnedMeshRenderer三角面数）
  • SkinnedMeshRenderer.sharedMesh.vertexCount（SkinnedMeshRenderer顶点数）

示例统计代码：

#if UNITY_EDITOR

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEditor;

public class CalculateMeshTris : MonoBehaviour
{
    [SerializeField] private bool active = true;

    private int verts;
    private int tris;

    private GUIStyle textStyle = new GUIStyle();

    private void Start()
    {
        textStyle.normal.background = null;
        textStyle.normal.textColor = new Color(1.0f,0.5f,0.0f);
        textStyle.fontSize = 30;

        if(active)
        {
            Selection.selectionChanged += CalculateVertsAndTris;
            CalculateVertsAndTris();
        }
    }

    private void CalculateVertsAndTris()
    {
        GameObject[] objs = Selection.gameObjects;

        int verts1 = 0, tris1 = 0, verts2 = 0, tris2 = 0;

        foreach(GameObject obj in objs)
        {
            MeshFilter[] filters = obj.GetComponentsInChildren();
            foreach(MeshFilter filter in filters)
            {
                tris1 += filter.sharedMesh.triangles.Length;
                verts1 += filter.sharedMesh.vertexCount;
            }

            SkinnedMeshRenderer[] renders = obj.GetComponentsInChildren();
            foreach(SkinnedMeshRenderer render in renders)
            {
                tris2 += render.sharedMesh.triangles.Length;
                verts2 += render.sharedMesh.vertexCount;
            }
        }
        tris1 /= 3;
        tris2 /= 3;

        verts = verts1 + verts2;
        tris = tris1 + tris2;

        Debug.Log(string.Format("verts: {0}+{1}={2}; tris: {3}+{4}={5}",verts1,verts2,verts,tris1,tris2,tris));
    }

    private void OnGUI()
    {
        if(active)
            GUILayout.Label(string.Format("verts: {0}; tris: {1}",verts,tris),textStyle);
    }
}

#endif