Material 冗余引用

由于 Unity 的机制，材质球会自动保存其上的纹理采样，即使更换 Shader 也不会把原来依 赖的纹理去除。所以可能会造成误依赖实际不需要的纹理带进包体的情况。从而造成内存的浪费

清除 ParticalSystem 无效 Mesh

	public static void CheckParticleSystemRenderer()
	{
		Object[] gos = Selection.GetFiltered(typeof(Object), SelectionMode.DeepAssets);
		foreach(var item in gos)
		{
			// Filter non-prefab type,
			if (PrefabUtility.GetPrefabType(item) != PrefabType.Prefab)
			{
				continue;
			}

			GameObject gameObj = item as GameObject;

			ParticleSystemRenderer[] renders = gameObj.GetComponentsInChildren<ParticleSystemRenderer>(true);
			foreach(var renderItem in renders)
			{
				if(renderItem.renderMode != ParticleSystemRenderMode.Mesh)
				{
					renderItem.mesh = null;
					EditorUtility.SetDirty(gameObj);
				}
			}
		}

		AssetDatabase.SaveAssets();
	}

清除材质球的无效纹理

	static void ClearMatProperties()
	{
		UnityEngine.Object[] objs = Selection.GetFiltered(typeof(Material), SelectionMode.DeepAssets);
		for (int i = 0; i < objs.Length; ++i)
		{
			Material mat = objs[i] as Material;

			if (mat)
			{
			    SerializedObject psSource = new SerializedObject(mat);
			    SerializedProperty emissionProperty = psSource.FindProperty("m_SavedProperties");
			    SerializedProperty texEnvs = emissionProperty.FindPropertyRelative("m_TexEnvs");

				if(CleanMaterialSerializedProperty (texEnvs, mat))
				{
					Debug.LogError("Find and clean useless texture propreties in " + mat.name);
				}

			    psSource.ApplyModifiedProperties();
			    EditorUtility.SetDirty(mat);
			}
		}

		AssetDatabase.SaveAssets();
	}	

	//true: has useless propeties
	private static bool CleanMaterialSerializedProperty(SerializedProperty property, Material mat)
	{
		bool res = false;

	    for (int j = property.arraySize - 1; j >= 0; j--)
	    {
	        //string propertyName =   property.GetArrayElementAtIndex(j).FindPropertyRelative("first").FindPropertyRelative("name").stringValue;
			
			SerializedProperty arrayElementAtIndex = property.GetArrayElementAtIndex(j);  
SerializedProperty serializedProperty3 = arrayElementAtIndex.FindPropertyRelative(“first”);  
string propertyName = serializedProperty3.stringValue;

	        if (!mat.HasProperty(propertyName))
	        {
				if(propertyName.Equals("_MainTex"))		
				{
					//_MainTex是内建属性，是置空不删除，否则UITexture等控件在获取mat.maintexture的时候会报错
					if (property.GetArrayElementAtIndex (j).FindPropertyRelative ("second").FindPropertyRelative ("m_Texture").objectReferenceValue != null) 
					{
						property.GetArrayElementAtIndex (j).FindPropertyRelative ("second").FindPropertyRelative ("m_Texture").objectReferenceValue = null;
						Debug.Log("Set _MainTex is null");
						res = true;
					}
				}
				else
				{
					property.DeleteArrayElementAtIndex(j);
					Debug.Log("Delete property in serialized object : " + propertyName);
					res = true;
				}
	        }
	    }
	    return res;
	}