扩展需求

在Scene视图中获取鼠标的位置

Demo

在Scene视图中，当鼠标点击时实例化一个Cube

重点部分

实现代码

using UnityEngine;
using UnityEditor;[CustomEditor(typeof(MyGrid))]
public class MyGridInspector : Editor
{MyGrid grid;public void OnEnable(){grid = (MyGrid)target;//初始化时获取引用SceneView.onSceneGUIDelegate += GridUpdate;//获取SceneView的输入}public void OnDisable(){// SceneView.onSceneGUIDelegate -= GridUpdate;}public override void OnInspectorGUI(){GUILayout.BeginHorizontal();GUILayout.Label("网格宽度");grid.width = EditorGUILayout.FloatField(grid.width, GUILayout.Width(50));GUILayout.EndHorizontal();GUILayout.BeginHorizontal();GUILayout.Label("网格高度");grid.height = EditorGUILayout.FloatField(grid.height, GUILayout.Width(50));GUILayout.EndHorizontal();if (GUILayout.Button("打开Grid Window", GUILayout.Width(255))){MyGridWindow window = (MyGridWindow)EditorWindow.GetWindow(typeof(MyGridWindow));window.Init();}SceneView.RepaintAll();//SceneView重绘}void GridUpdate(SceneView sceneview){Event e = Event.current;//获取事件if (e.isKey && e.character == 'a'){//GameObject obj = GameObject.CreatePrimitive(PrimitiveType.Cube);GameObject obj;//如果选中Object//if (Selection.activeObject)//{//    obj = (GameObject)Instantiate(Selection.activeObject);//    obj.transform.position = Vector3.zero;//}//在Editor模式实例化一个Prefab//if (Selection.activeObject)//{//    //找到Prefab//    Object prefab =  PrefabUtility.GetPrefabParent(Selection.activeObject);//    if (prefab)//    {//        obj = (GameObject)PrefabUtility.InstantiatePrefab(prefab);//        obj.transform.position = Vector3.zero;//    }//}//根据鼠标点击的位置实例化Prefabif (Selection.activeObject){//屏幕的鼠标坐标转换成世界坐标/**
                 * 1、从屏幕发出射线
                 * 2、我们需要转化事件的屏幕空间的空间是可以接受的screenpointtoray()
                 * 3、e.mousePosition 左上角坐标(0,0)，右下角坐标(Camera.current.pixelWidth, -Camera.current.pixelHeight)，
                      把它转换成世界坐标变为左下角(0,9),右上角(Camera.current.pixelWidth, Camera.current.pixelHeight)
                 *//*
                 Ray r = Camera.current.ScreenPointToRay(new Vector3(e.mousePosition.x, -e.mousePosition.y + Camera.current.pixelHeight));
                 Vector3 mousePos = r.origin;//mousepos向量保存射线的来源
                 //找到Prefab
                 Object prefab = PrefabUtility.GetPrefabParent(Selection.activeObject);
                 if (prefab)
                 {                     obj = (GameObject)PrefabUtility.InstantiatePrefab(prefab);
                     obj.transform.position = new Vector3(mousePos.x,mousePos.y,0.0f);
                 }*/}//将Cube对齐到网格中心位置？if (Selection.activeObject){Ray r = Camera.current.ScreenPointToRay(new Vector3(e.mousePosition.x, -e.mousePosition.y + Camera.current.pixelHeight));Vector3 mousePos = r.origin;//mousepos向量保存射线的来源//找到PrefabObject prefab = PrefabUtility.GetPrefabParent(Selection.activeObject);if (prefab){obj = (GameObject)PrefabUtility.InstantiatePrefab(prefab);Vector3 aligned = new Vector3(Mathf.Floor(mousePos.x / grid.width) * grid.width + grid.width / 2.0f,Mathf.Floor(mousePos.y / grid.height) * grid.height + grid.height / 2.0f,0.0f);obj.transform.position = aligned;}}}else if (e.isKey && e.character == 'n' && e.clickCount==0) //在当前鼠标位置创建一个Cube{Ray r = Camera.current.ScreenPointToRay(new Vector3(e.mousePosition.x, -e.mousePosition.y + Camera.current.pixelHeight));Vector3 mousePos = r.origin;//mousepos向量保存射线的来源GameObject obj = GameObject.CreatePrimitive(PrimitiveType.Cube);Vector3 aligned = new Vector3(Mathf.Floor(mousePos.x / grid.width) * grid.width + grid.width / 2.0f,Mathf.Floor(mousePos.y / grid.height) * grid.height + grid.height / 2.0f,0.0f);obj.transform.position = aligned;//注册撤消操作Undo.RegisterCreatedObjectUndo(obj, "Create" + obj.name);Debug.Log("create");}else if (e.isKey && e.character == 'd')//删除选中的GameObject{foreach (GameObject obj in Selection.gameObjects){Debug.Log(obj.name);DestroyImmediate(obj);}}else if (e.isKey && e.character == '1'){GameObject obj;if (Selection.activeObject){Ray r = Camera.current.ScreenPointToRay(new Vector3(e.mousePosition.x, -e.mousePosition.y + Camera.current.pixelHeight));Vector3 mousePos = r.origin;//mousepos向量保存射线的来源//找到PrefabObject prefab = PrefabUtility.GetPrefabParent(Selection.activeObject);if (prefab){obj = (GameObject)PrefabUtility.InstantiatePrefab(prefab);Vector3 aligned = new Vector3(Mathf.Floor(mousePos.x / grid.width) * grid.width + grid.width / 2.0f,Mathf.Floor(mousePos.y / grid.height) * grid.height + grid.height / 2.0f,0.0f);obj.transform.position = aligned;//注册撤消操作Undo.RegisterCreatedObjectUndo(obj, "Create" + obj.name);Debug.Log("create");}}}//撤消单个对象实例else if (e.isKey && e.character == '4'){GameObject obj;if (Selection.activeObject){Ray r = Camera.current.ScreenPointToRay(new Vector3(e.mousePosition.x, -e.mousePosition.y + Camera.current.pixelHeight));Vector3 mousePos = r.origin;//mousepos向量保存射线的来源//找到PrefabObject prefab = PrefabUtility.GetPrefabParent(Selection.activeObject);if (prefab){Undo.IncrementCurrentGroup();obj = (GameObject)PrefabUtility.InstantiatePrefab(prefab);Vector3 aligned = new Vector3(Mathf.Floor(mousePos.x / grid.width) * grid.width + grid.width / 2.0f,Mathf.Floor(mousePos.y / grid.height) * grid.height + grid.height / 2.0f,0.0f);obj.transform.position = aligned;//注册撤消操作Undo.RegisterCreatedObjectUndo(obj, "Create" + obj.name);Debug.Log("create");}}}}
}

参考资料

http://code.tutsplus.com/tutorials/how-to-add-your-own-tools-to-unitys-editor--active-10047