选中ScriptableObject文件时如何在Scene View中绘制Gizmos？

我希望在编辑模式下可视化ResourceAreas的位置，编写了编辑器工具代码，但选中ResourceAreas ScriptableObject文件后，Scene View中并未显示对应的Gizmos。

编辑器代码 #

using UnityEngine;
using UnityEditor;

[CustomEditor(typeof(ResourceAreas))]
public class ResourceAreasEditor : Editor
{
    void OnSceneGUI()
    {
        ResourceAreas resourceAreas = (ResourceAreas)target;

        foreach (ResourceArea area in resourceAreas.resourceAreas)
        {
            Handles.color = Color.red;
            Handles.DrawWireDisc(area.center, new Vector3(0,1,0), area.radius);

            EditorGUI.BeginChangeCheck();
            Vector3 newCenter = Handles.PositionHandle(area.center, Quaternion.identity);
            if (EditorGUI.EndChangeCheck())
            {
                Undo.RecordObject(resourceAreas, "Move Resource Area Center");
                area.center = newCenter;
                EditorUtility.SetDirty(resourceAreas);
            }
        }
    }
}

ResourceAreas相关代码 #

using UnityEngine;

[System.Serializable]
public class ResourceArea
{
    public string resourceName;
    public Vector3 center;  // 地形空间中的中心点
    public float radius;    // 资源区域半径
    public int resourceCount;
}

[CreateAssetMenu(fileName = "ResourceAreas", menuName = "ScriptableObjects/ResourceAreas", order = 1)]
public class ResourceAreas : ScriptableObject
{
    public ResourceArea[] resourceAreas;
}

补充说明 #

Inspector中已正常显示ResourceAreas的数据：包含多个ResourceArea条目，每个条目有名称输入框、center坐标字段、radius数值框和resourceCount数值框，但Scene View无任何Gizmos显示。

解决方案 #

ScriptableObject并非场景内的GameObject，默认不会触发OnSceneGUI的绘制逻辑。要实现选中ScriptableObject时在Scene View显示Gizmos，需要修改编辑器代码，通过注册Scene View回调来主动触发绘制：

修改后的编辑器代码：

using UnityEngine;
using UnityEditor;

[CustomEditor(typeof(ResourceAreas))]
[InitializeOnLoad]
public class ResourceAreasEditor : Editor
{
    static ResourceAreasEditor()
    {
        // 注册Scene View的绘制回调
        SceneView.duringSceneGui += DrawResourceAreasInScene;
    }

    static void DrawResourceAreasInScene(SceneView sceneView)
    {
        // 仅在选中ResourceAreas对象时绘制
        var selectedResourceAreas = Selection.activeObject as ResourceAreas;
        if (selectedResourceAreas == null) return;

        foreach (ResourceArea area in selectedResourceAreas.resourceAreas)
        {
            Handles.color = Color.red;
            Handles.DrawWireDisc(area.center, Vector3.up, area.radius);

            EditorGUI.BeginChangeCheck();
            Vector3 newCenter = Handles.PositionHandle(area.center, Quaternion.identity);
            if (EditorGUI.EndChangeCheck())
            {
                Undo.RecordObject(selectedResourceAreas, "Move Resource Area Center");
                area.center = newCenter;
                EditorUtility.SetDirty(selectedResourceAreas);
            }
        }
    }

    void OnDisable()
    {
        // 移除回调避免内存泄漏
        SceneView.duringSceneGui -= DrawResourceAreasInScene;
    }
}

额外注意事项 #

• 确保Scene View顶部的Gizmos按钮处于开启状态
• 检查center字段的坐标值是否在当前场景的可视范围内（比如如果是地形空间坐标，要确认地形存在且坐标对应）

内容的提问来源于stack exchange，提问作者sdfesgfsef