U3D之Editor扩展学习
Unity3D提供了强大的编辑器扩展机制，在项目开发中，如果可以将一些繁琐的工作放在编辑器扩展中进行，则会大大提高效率。本文对编辑器扩展进行了一些总结，希望对有兴趣编写编辑器扩展的开发人员有所帮助。当我们编写一个编辑器扩展时，一般可以从以下四个类继承：
1 . ScriptableObject
最常见的小功能扩展，一般不用窗口的编辑扩展，可以从这个类中继承，如以下代码所示：
using UnityEngine; using UnityEditor; using System.Collections; public class AddChild : ScriptableObject { [MenuItem ("GameObject/Add Child ^n")] static void MenuAddChild() { Transform[] transforms = Selection.GetTransforms(SelectionMode.TopLevel | SelectionMode.OnlyUserModifiable); foreach(Transform transform in transforms) { GameObject newChild = new GameObject("_Child"); newChild.transform.parent = transform; } } }
这个扩展脚本从菜单的“GameObject->Add Child”启动，功能是给Hierarchy窗口中选中的对GameObject添加一个名字为“_Child”的子GameObject，这样可以免去从Hierarchy窗口的根节点拖拽新创建的GameObject到当前选中节点的麻烦，因为在Unity3D编辑器中，创建一个EmptyObject会在Hierarchy窗口的根节点出现，无论当前选中的节点对象是哪个。
2 .ScriptableWizard
需要对扩展的参数进行设置，然后再进行功能触发的，可以从这个类进行派生。它已经定制好了四个消息响应函数，开发者对其进行填充即可。
(1) OnWizardUpdate
当扩展窗口打开时或用户对窗口的内容进行改动时，会调用此函数。一般会在这里面显示帮助文字和进行内容有效性验证；
(2)OnWizardCreate
这是用户点击窗口的Create按钮时进行的操作，从ScriptableWizard的名字可以看出，这是一种类似向导的窗口 ，而这种窗口我们在Visual Studio中经常会使用到，如下图：
只不过Unity3D中的ScriptableWizard窗口只能进行小于或等于两个按钮的定制，一个就是所谓的Create按钮，另外一个则笼统称之为Other按钮。ScriptableWizard.DisplayWizard这个静态函数用于对ScriptableWizard窗口标题和按钮名字的定制。
(3) OnDrawGizmos
在窗口可见时，每一帧都会调用这个函数。在其中进行Gizmos的绘制，也就是辅助编辑的线框体。Unity的Gizmos类提供了DrawRayDrawLine ,DrawWireSphere ,DrawSphere ,DrawWireCube ,DrawCubeDrawIcon ,DrawGUITexture 功能。这个功能在Unity3D 的3.4版本中测试了一下，发现没有任何Gizmos绘制出来
(4) OnWizardOtherButton
本文在(2) 中已经提及，ScriptableWizard窗口最多可以定制两个按钮，一个是Create，另外一个称之为Other，这个函数会在other按钮被点击时调用。下面是一个使用ScriptableWizard进行编辑扩展的例子：
<span style="font-size: 18px;">using UnityEditor; using UnityEngine; using System.Collections; /// <summary> /// 对于选定GameObject，进行指定component的批量添加 /// </summary> public class AddRemoveComponentsRecursively : ScriptableWizard { public string componentType = null; /// <summary> /// 当没有任何GameObject被选中的时候，将菜单disable（注意，这个函数名可以随意取） /// </summary> /// <returns></returns> [MenuItem("GameObject/Add or remove components recursively...", true)] static bool CreateWindowDisabled() { return Selection.activeTransform; } /// <summary> /// 创建编辑窗口（注意，这个函数名可以随意取） /// </summary> [MenuItem("GameObject/Add or remove components recursively...")] static void CreateWindow() { // 定制窗口标题和按钮，其中第二个参数是Create按钮，第三个则属于other按钮 // 如果不想使用other按钮，则可调用DisplayWizard的两参数版本 ScriptableWizard.DisplayWizard<AddRemoveComponentsRecursively>( "Add or remove components recursivly", "Add", "Remove"); } /// <summary> /// 窗口创建或窗口内容更改时调用 /// </summary> void OnWizardUpdate() { helpString = "Note: Duplicates are not created"; if (string.IsNullOrEmpty(componentType)) { errorString = "Please enter component class name"; isValid = false; } else { errorString = ""; isValid = true; } } /// <summary> /// 点击Add按钮（即Create按钮）调用 /// </summary> void OnWizardCreate() { int c = 0; Transform[] ts = Selection.GetTransforms(SelectionMode.Deep); foreach (Transform t in ts) { if (t.gameObject.GetComponent(componentType) == null) { if (t.gameObject.AddComponent(componentType) == null) { Debug.LogWarning("Component of type " + componentType + " does not exist"); return; } c++; } } Debug.Log("Added " + c + " components of type " + componentType); } /// <summary> /// 点击Remove（即other按钮）调用 /// </summary> void OnWizardOtherButton() { int c = 0; Transform[] ts = Selection.GetTransforms(SelectionMode.Deep); foreach (Transform t in ts) { if (t.GetComponent(componentType) != null) { DestroyImmediate(t.GetComponent(componentType)); c++; } } Debug.Log("Removed " + c + " components of type " + componentType); Close(); } }</span>
其运行窗口如下所示：
3 . EditorWindow
较复杂的功能，需要多个灵活的控件，实现自由浮动和加入其他窗口的tab，可以从这个类派生，这种窗口的窗体功能和Scene，Hierarchy等窗口完全一致。下面这个例子实现了GameObject的空间对齐和拷贝（也就是将GameObject A作为基准，选中其他的GameObject进行对准或空间位置拷贝），对齐和拷贝提高了了开发者摆放物件的效率；另外还有随机和噪声，后两者用于摆放大量同类物件的时候可以使用，比如一大堆散落的瓶子。
<span style="font-size: 18px;">// ///////////////////////////////////////////////////////////////////////////////////////////////////////// // // Transform Utilities. // // This window contains four useful tools for asset placing and manipulation: Align, Copy, Randomize and Add noise. // // Put this into Assets/Editor and once compiled by Unity you find // the new functionality in Window -> TransformUtilities, or simply press Ctrl+t (Cmd+t for Mac users) // // Developed by Daniel // http://www.silentkraken.com // e-mail: [email protected] // // ///////////////////////////////////////////////////////////////////////////////////////////////////////// using UnityEngine; using UnityEditor; public class TransformUtilitiesWindow : EditorWindow { //Window control values public int toolbarOption = 0; public string[] toolbarTexts = {"Align", "Copy", "Randomize", "Add noise"}; private bool xCheckbox = true; private bool yCheckbox = true; private bool zCheckbox = true; private Transform source; private float randomRangeMin = 0f; private float randomRangeMax = 1f; private int alignSelectionOption = 0; private int alignSourceOption = 0; /// <summary> /// Retrives the TransformUtilities window or creates a new one /// </summary> [MenuItem("Window/TransformUtilities %t")] static void Init() { TransformUtilitiesWindow window = (TransformUtilitiesWindow)EditorWindow.GetWindow(typeof(TransformUtilitiesWindow)); window.Show(); } /// <summary> /// Window drawing operations /// </summary> void OnGUI () { toolbarOption = GUILayout.Toolbar(toolbarOption, toolbarTexts); switch (toolbarOption) { case 0: CreateAxisCheckboxes("Align"); CreateAlignTransformWindow(); break; case 1: CreateAxisCheckboxes("Copy"); CreateCopyTransformWindow(); break; case 2: CreateAxisCheckboxes("Randomize"); CreateRandomizeTransformWindow(); break; case 3: CreateAxisCheckboxes("Add noise"); CreateAddNoiseToTransformWindow(); break; } } /// <summary> /// Draws the 3 axis checkboxes (x y z) /// </summary> /// <param name="operationName"></param> private void CreateAxisCheckboxes(string operationName) { GUILayout.Label(operationName + " on axis", EditorStyles.boldLabel); GUILayout.BeginHorizontal(); xCheckbox = GUILayout.Toggle(xCheckbox, "X"); yCheckbox = GUILayout.Toggle(yCheckbox, "Y"); zCheckbox = GUILayout.Toggle(zCheckbox, "Z"); GUILayout.EndHorizontal(); EditorGUILayout.Space(); } /// <summary> /// Draws the range min and max fields /// </summary> private void CreateRangeFields() { GUILayout.Label("Range", EditorStyles.boldLabel); GUILayout.BeginHorizontal(); randomRangeMin = EditorGUILayout.FloatField("Min:", randomRangeMin); randomRangeMax = EditorGUILayout.FloatField("Max:", randomRangeMax); GUILayout.EndHorizontal(); EditorGUILayout.Space(); } /// <summary> /// Creates the Align transform window /// </summary> private void CreateAlignTransformWindow() { //Source transform GUILayout.BeginHorizontal(); GUILayout.Label("Align to: \t"); source = EditorGUILayout.ObjectField(source, typeof(Transform)) as Transform; GUILayout.EndHorizontal(); string[] texts = new string[4] { "Min", "Max", "Center", "Pivot" }; //Display align options EditorGUILayout.BeginHorizontal(); EditorGUILayout.BeginVertical(); GUILayout.Label("Selection:", EditorStyles.boldLabel); alignSelectionOption = GUILayout.SelectionGrid(alignSelectionOption, texts, 1); EditorGUILayout.EndVertical(); EditorGUILayout.BeginVertical(); GUILayout.Label("Source:", EditorStyles.boldLabel); alignSourceOption = GUILayout.SelectionGrid(alignSourceOption, texts, 1); EditorGUILayout.EndVertical(); EditorGUILayout.EndHorizontal(); EditorGUILayout.Space(); //Position if (GUILayout.Button("Align")) { if (source != null) { //Add a temporary box collider to the source if it doesn't have one Collider sourceCollider = source.collider; bool destroySourceCollider = false; if (sourceCollider == null) { sourceCollider = source.gameObject.AddComponent<BoxCollider>(); destroySourceCollider = true; } foreach (Transform t in Selection.transforms) { //Add a temporary box collider to the transform if it doesn't have one Collider transformCollider = t.collider; bool destroyTransformCollider = false; if (transformCollider == null) { transformCollider = t.gameObject.AddComponent<BoxCollider>(); destroyTransformCollider = true; } Vector3 sourceAlignData = new Vector3(); Vector3 transformAlignData = new Vector3(); //Transform switch (alignSelectionOption) { case 0: //Min transformAlignData = transformCollider.bounds.min; break; case 1: //Max transformAlignData = transformCollider.bounds.max; break; case 2: //Center transformAlignData = transformCollider.bounds.center; break; case 3: //Pivot transformAlignData = transformCollider.transform.position; break; } //Source switch (alignSourceOption) { case 0: //Min sourceAlignData = sourceCollider.bounds.min; break; case 1: //Max sourceAlignData = sourceCollider.bounds.max; break; case 2: //Center sourceAlignData = sourceCollider.bounds.center; break; case 3: //Pivot sourceAlignData = sourceCollider.transform.position; break; } Vector3 tmp = new Vector3(); tmp.x = xCheckbox ? sourceAlignData.x - (transformAlignData.x - t.position.x) : t.position.x; tmp.y = yCheckbox ? sourceAlignData.y - (transformAlignData.y - t.position.y) : t.position.y; tmp.z = zCheckbox ? sourceAlignData.z - (transformAlignData.z - t.position.z) : t.position.z; //Register the Undo Undo.RegisterUndo(t, "Align " + t.gameObject.name + " to " + source.gameObject.name); t.position = tmp; //Ugly hack! //Unity needs to update the collider of the selection to it's new position //(it stores in cache the collider data) //We can force the update by a change in a public variable (shown in the inspector), //then a call SetDirty to update the collider (it won't work if all inspector variables are the same). //But we want to restore the changed property to what it was so we do it twice. transformCollider.isTrigger = !transformCollider.isTrigger; EditorUtility.SetDirty(transformCollider); transformCollider.isTrigger = !transformCollider.isTrigger; EditorUtility.SetDirty(transformCollider); //Destroy the collider we added if (destroyTransformCollider) { DestroyImmediate(transformCollider); } } //Destroy the collider we added if (destroySourceCollider) { DestroyImmediate(sourceCollider); } } else { EditorUtility.DisplayDialog("Error", "There is no source transform", "Ok"); EditorApplication.Beep(); } } } /// <summary> /// Creates the copy transform window /// </summary> private void CreateCopyTransformWindow() { //Source transform GUILayout.BeginHorizontal(); GUILayout.Label("Copy from: \t"); source = EditorGUILayout.ObjectField(source, typeof(Transform)) as Transform; GUILayout.EndHorizontal(); EditorGUILayout.Space(); //Position if (GUILayout.Button("Copy Position")) { if (source != null) { foreach (Transform t in Selection.transforms) { Vector3 tmp = new Vector3(); tmp.x = xCheckbox ? source.position.x : t.position.x; tmp.y = yCheckbox ? source.position.y : t.position.y; tmp.z = zCheckbox ? source.position.z : t.position.z; Undo.RegisterUndo(t, "Copy position"); t.position = tmp; } } else { EditorUtility.DisplayDialog("Error", "There is no source transform", "Ok"); EditorApplication.Beep(); } } //Rotation if (GUILayout.Button("Copy Rotation")) { if (source != null) { foreach (Transform t in Selection.transforms) { Vector3 tmp = new Vector3(); tmp.x = xCheckbox ? source.rotation.eulerAngles.x : t.rotation.eulerAngles.x; tmp.y = yCheckbox ? source.rotation.eulerAngles.y : t.rotation.eulerAngles.y; tmp.z = zCheckbox ? source.rotation.eulerAngles.z : t.rotation.eulerAngles.z; Quaternion tmp2 = t.rotation; tmp2.eulerAngles = tmp; Undo.RegisterUndo(t, "Copy rotation"); t.rotation = tmp2; } } else { EditorUtility.DisplayDialog("Error", "There is no source transform", "Ok"); EditorApplication.Beep(); } } //Local Scale if (GUILayout.Button("Copy Local Scale")) { if (source != null) { foreach (Transform t in Selection.transforms) { Vector3 tmp = new Vector3(); tmp.x = xCheckbox ? source.localScale.x : t.localScale.x; tmp.y = yCheckbox ? source.localScale.y : t.localScale.y; tmp.z = zCheckbox ? source.localScale.z : t.localScale.z; Undo.RegisterUndo(t, "Copy local scale"); t.localScale = tmp; } } else { EditorUtility.DisplayDialog("Error", "There is no source transform", "Ok"); EditorApplication.Beep(); } } } /// <summary> /// Creates the Randomize transform window /// </summary> private void CreateRandomizeTransformWindow() { CreateRangeFields(); //Position if (GUILayout.Button("Randomize Position")) { foreach (Transform t in Selection.transforms) { Vector3 tmp = new Vector3(); tmp.x = xCheckbox ? Random.Range(randomRangeMin, randomRangeMax) : t.position.x; tmp.y = yCheckbox ? Random.Range(randomRangeMin, randomRangeMax) : t.position.y; tmp.z = zCheckbox ? Random.Range(randomRangeMin, randomRangeMax) : t.position.z; Undo.RegisterUndo(t, "Randomize position"); t.position = tmp; } } //Rotation if (GUILayout.Button("Randomize Rotation")) { foreach (Transform t in Selection.transforms) { Vector3 tmp = new Vector3(); tmp.x = xCheckbox ? Random.Range(randomRangeMin, randomRangeMax) : t.rotation.eulerAngles.x; tmp.y = yCheckbox ? Random.Range(randomRangeMin, randomRangeMax) : t.rotation.eulerAngles.y; tmp.z = zCheckbox ? Random.Range(randomRangeMin, randomRangeMax) : t.rotation.eulerAngles.z; Quaternion tmp2 = t.rotation; tmp2.eulerAngles = tmp; Undo.RegisterUndo(t, "Randomize rotation"); t.rotation = tmp2; } } //Local Scale if (GUILayout.Button("Randomize Local Scale")) { foreach (Transform t in Selection.transforms) { Vector3 tmp = new Vector3(); tmp.x = xCheckbox ? Random.Range(randomRangeMin, randomRangeMax) : t.localScale.x; tmp.y = yCheckbox ? Random.Range(randomRangeMin, randomRangeMax) : t.localScale.y; tmp.z = zCheckbox ? Random.Range(randomRangeMin, randomRangeMax) : t.localScale.z; Undo.RegisterUndo(t, "Randomize local scale"); t.localScale = tmp; } } } /// <summary> /// Creates the Add Noise To Transform window /// </summary> private void CreateAddNoiseToTransformWindow() { CreateRangeFields(); //Position if (GUILayout.Button("Add noise to Position")) { foreach (Transform t in Selection.transforms) { Vector3 tmp = new Vector3(); tmp.x = xCheckbox ? Random.Range(randomRangeMin, randomRangeMax) : 0; tmp.y = yCheckbox ? Random.Range(randomRangeMin, randomRangeMax) : 0; tmp.z = zCheckbox ? Random.Range(randomRangeMin, randomRangeMax) : 0; Undo.RegisterUndo(t, "Add noise to position"); t.position += tmp; } } //Rotation if (GUILayout.Button("Add noise to Rotation")) { foreach (Transform t in Selection.transforms) { Vector3 tmp = new Vector3(); tmp.x = xCheckbox ? t.rotation.eulerAngles.x + Random.Range(randomRangeMin, randomRangeMax) : 0; tmp.y = yCheckbox ? t.rotation.eulerAngles.y + Random.Range(randomRangeMin, randomRangeMax) : 0; tmp.z = zCheckbox ? t.rotation.eulerAngles.z + Random.Range(randomRangeMin, randomRangeMax) : 0; Undo.RegisterUndo(t, "Add noise to rotation"); t.rotation = Quaternion.Euler(tmp); } } //Local Scale if (GUILayout.Button("Add noise to Local Scale")) { foreach (Transform t in Selection.transforms) { Vector3 tmp = new Vector3(); tmp.x = xCheckbox ? Random.Range(randomRangeMin, randomRangeMax) : 0; tmp.y = yCheckbox ? Random.Range(randomRangeMin, randomRangeMax) : 0; tmp.z = zCheckbox ? Random.Range(randomRangeMin, randomRangeMax) : 0; Undo.RegisterUndo(t, "Add noise to local scale"); t.localScale += tmp; } } } }</span>
其窗口如下图所示：
4. Editor
对某自定义组件进行观察的Inspector窗口，可以从它派生。如下代码所示：
代码片段1定义了一个名为Star的组件：
<span style="font-size: 18px;">using System; using UnityEngine; [RequireComponent(typeof(MeshFilter), typeof(MeshRenderer))] public class Star : MonoBehaviour { [Serializable] public class Point { public Color color; public Vector3 offset; } public Point[] points; public int frequency = 1; public Color centerColor; private Mesh mesh; private Vector3[] vertices; private Color[] colors; private int[] triangles; void Start () { GetComponent<MeshFilter>().mesh = mesh = new Mesh(); mesh.name = "Star Mesh"; if(frequency < 1){ frequency = 1; } if(points == null || points.Length == 0){ points = new Point[]{ new Point()}; } int numberOfPoints = frequency * points.Length; vertices = new Vector3[numberOfPoints + 1]; colors = new Color[numberOfPoints + 1]; triangles = new int[numberOfPoints * 3]; float angle = -360f / numberOfPoints; colors[0] = centerColor; for(int iF = 0, v = 1, t = 1; iF < frequency; iF++){ for(int iP = 0; iP < points.Length; iP += 1, v += 1, t += 3){ vertices[v] = Quaternion.Euler(0f, 0f, angle * (v - 1)) * points[iP].offset; colors[v] = points[iP].color; triangles[t] = v; triangles[t + 1] = v + 1; } } triangles[triangles.Length - 1] = 1; mesh.vertices = vertices; mesh.colors = colors; mesh.triangles = triangles; } }</span>
代码片段2定义了对Star组件进行观测的Inspector窗口：
<span style="font-size: 18px;">using UnityEditor; using UnityEngine; [CustomEditor(typeof(Star))] public class StarInspector : Editor { private static GUIContent insertContent = new GUIContent("+", "duplicate this point"), deleteContent = new GUIContent("-", "delete this point"), pointContent = GUIContent.none; private static GUILayoutOption buttonWidth = GUILayout.MaxWidth(20f), colorWidth = GUILayout.MaxWidth(50f); private SerializedObject star; private SerializedProperty points, frequency, centerColor; void OnEnable () { … } public override void OnInspectorGUI () { star.Update(); GUILayout.Label("Points"); for(int i = 0; i < points.arraySize; i++){ EditorGUILayout.BeginHorizontal(); SerializedProperty point = points.GetArrayElementAtIndex(i); EditorGUILayout.PropertyField(point.FindPropertyRelative("offset"), pointContent); EditorGUILayout.PropertyField(point.FindPropertyRelative("color"), pointContent, colorWidth); if(GUILayout.Button(insertContent, EditorStyles.miniButtonLeft, buttonWidth)){ points.InsertArrayElementAtIndex(i); } if(GUILayout.Button(deleteContent, EditorStyles.miniButtonRight, buttonWidth)){ points.DeleteArrayElementAtIndex(i); } EditorGUILayout.EndHorizontal(); } EditorGUILayout.PropertyField(frequency); EditorGUILayout.PropertyField(centerColor); star.ApplyModifiedProperties(); } }</span>
其Inspector窗口如下图所示：
说到这里，大家对ScriptableObject, ScriptableWizard, EditorWindow和Editor应该都有应有了一定了解。其中EditorWindow和Editor都继承了ScriptableObject，而ScritableWizard则继承了EditorWindow派。在实际开发应用中，应该根据需求的特点，灵活使用这四个类进行编辑器扩展。
参考资料：
1. http://catlikecoding.com/unity/tutorials/star/
2. http://www.unifycommunity.com/wiki
3. http://www.blog.silentkraken.com/2010/02/06/transformutilities/
4.http://unity3d.com/support/documentation/ScriptReference
转：http://blog.csdn.net/jjiss318/article/details/7435708