[游戏开发]Unity - 搬砖日志 - Occlusion Culling 关闭动态遮挡剔除 Renderer.allowOcclusionWhenDynamic = false

上面的测试数据是基于 小米5 真机上测试的

可以看到 Profiler : PlayerLoop/PostLateUpdate.FinishFrameRendering/Camera.Render/Culling/SceneCulling/CullSendEvents/WaitForJobGroupID/CullSceneDynamicObjects/CullDynamicObjectsWithUmbra 的消耗是有一部分的，消耗了 3.12 ms

然后上图是通过脚本遍历大部分 Renderer ，并设置： allowOcclusionWhenDynamic = false; （还有大概3~4 个墙体，地表，等，没有禁用，所以还是有一丢丢消耗），设置的脚本如下：

    public void OnToggleDynamicObjOC()
    {
        renderers.Clear();
        dynamicObjRoot.GetComponentsInChildren<Renderer>(true, renderers);

        var setValue = !curEnabledDynamicOC;

        for (int i = 0; i < renderers.Count; i++)
        {
            var renderer = renderers[i];
            renderer.allowOcclusionWhenDynamic = setValue;
        }

        curEnabledDynamicOC = setValue;

        toggleDyanmicOCBtnText.text = $"Cur DynamicOC : {setValue}";
    }

在 Unity 官方 API 文档，还有 Unity 论坛上，Baidu, Goggle 都没有找到 Unity 有暴露一个总开关的地方
（除非有 Unity 源码，可以自行扩展出一个给 C# 脚本控制的总开关，否则只能用回上面的脚本遍历处理）

而工具刚刚写好，就一个脚本完事：

// jave.lin 2021/08/05
// 禁用 Renderer dynamic OC 的工具

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

public class DisableRendererOCEditorWindow : EditorWindow
{
    public enum eDisableRet
    {
        Success,
        Cancel,
        Error,
    }

    private List<Renderer> renderersHelper = new List<Renderer>();
    private HashSet<string> handledSetsHelper = new HashSet<string>();

    [MenuItem("Tools/资源工具/禁用 Renderer dynamic OC 的工具")]
    public static void _Show()
    {
        var win = EditorWindow.GetWindow<DisableRendererOCEditorWindow>();
        win.titleContent = new GUIContent("禁用 Renderer dynamic OC 的工具");
        win.Show();
    }
    private void OnGUI()
    {
        if (GUILayout.Button("关闭场景中所有涉及到的 prefab 的Renderer.allowOcclusionWhenDynamic"))
        {
            Handle();
        }
    }

    private void Handle()
    {
        var scene = EditorSceneManager.GetActiveScene();
        if (!scene.IsValid())
        {
            return;
        }

        handledSetsHelper.Clear();

        var goList = new List<GameObject>();
        // 提取 go
        FilterGOs(scene, goList);

        // 禁止 go 内的 renderer dynamic oc
        var handleRet = DisableDynamicOC(goList);
        switch (handleRet)
        {
            case eDisableRet.Success:
                EditorUtility.DisplayDialog("Disabled Dynamic Occlusion Successfully", "Disabled Dynamic Occlusion Successfully", "OK");
                break;
            case eDisableRet.Cancel:
                Debug.Log("Disabled Dynamic Occlusion was cancel!");
                break;
            case eDisableRet.Error:
                // nops
                break;
            default:
                break;
        }
    }

    private void FilterGOs(Scene scene, List<GameObject> result)
    {
        var firstRootGOs = scene.GetRootGameObjects();
        for (int i = 0; i < firstRootGOs.Length; i++)
        {
            _FilterGOs(firstRootGOs[i], result);
        }
    }

    private void _FilterGOs(GameObject go, List<GameObject> result)
    {
        var status = PrefabUtility.GetPrefabInstanceStatus(go);
        Debug.Log($"go.name : {go.name}, prefab inst status : {status}");
        if (status == PrefabInstanceStatus.NotAPrefab)
        {
            for (int transIDX = 0; transIDX < go.transform.childCount; transIDX++)
            {
                _FilterGOs(go.transform.GetChild(transIDX).gameObject, result);
            }
            return;
        }

        var path = PrefabUtility.GetPrefabAssetPathOfNearestInstanceRoot(go);
        Debug.Log($"go.name : {go.name}, prefab asset path : {path}");
        if (handledSetsHelper.Contains(path))
        {
            Debug.Log($"{path}, renderer.allowOcclusionWhenDynamic = false; was handled, so skipped this time. ");
            return;
        }
        result.Add(go);
    }

    private eDisableRet DisableDynamicOC(List<GameObject> goList)
    {
        try
        {
            var goCount = goList.Count;
            for (int goIDX = 0; goIDX < goCount; goIDX++)
            {
                var cancel = EditorUtility.DisplayCancelableProgressBar("Handling...", $"Handling {goIDX}/{goCount}", (float)goIDX / goCount);
                if (cancel)
                {
                    return eDisableRet.Cancel;
                }

                var go = goList[goIDX];
                var path = PrefabUtility.GetPrefabAssetPathOfNearestInstanceRoot(go);
                if (handledSetsHelper.Contains(path))
                {
                    Debug.Log($"{path}, renderer.allowOcclusionWhenDynamic = false; was handled, so skipped this time. ");
                    continue;
                }

                renderersHelper.Clear();
                go.GetComponentsInChildren<Renderer>(renderersHelper);

                var needToUpdate = false;
                for (int i = 0; i < renderersHelper.Count; i++)
                {
                    var renderer = renderersHelper[i];
                    if (renderer.allowOcclusionWhenDynamic)
                    {
                        renderer.allowOcclusionWhenDynamic = false;
                        needToUpdate = true; // 该标识：只要有一个属性调整了，就整个 prefab apply
                    }
                }
                // 如果需要更新属性才更新 prefab
                if (needToUpdate)
                {
                    //var pmods = PrefabUtility.GetPropertyModifications(go);
                    //PrefabUtility.SetPropertyModifications(go, pmods);
                    PrefabUtility.ApplyPrefabInstance(go, InteractionMode.AutomatedAction);
                    handledSetsHelper.Add(path);
                }
            }
            return eDisableRet.Success;
        }
        catch (Exception er)
        {
            Debug.LogError($"{nameof(DisableRendererOCEditorWindow)}.{nameof(DisableDynamicOC)} error : {er}");
            return eDisableRet.Error;
        }
        finally
        {
            EditorUtility.ClearProgressBar();
        }
    }
}

当场景比较大的时候，这块处理会比较久，因为每一个 Prefab Apply Changes 都是一个文件 IO 的写入操作