IDrawSelectedHandles.OnDrawHandles

描述

实现此方法以在自定义编辑器工具可用时绘制非交互式手柄。

当当前选择项有自定义编辑器工具可用时，此方法会被调用。使用此方法在 SceneView 中绘制信息。自定义编辑器工具是 EditorTool，其目标类型由 EditorToolAttribute 指定。

using System;
using UnityEngine;
using UnityEditor;
using UnityEditor.EditorTools;

[EditorTool("Light Tool", typeof(Light))]
public class CustomEditorLightTool : EditorTool, IDrawSelectedHandles
{
    // OnToolGUI is called when the tool is active. Interactive handles belong here.
    public override void OnToolGUI(EditorWindow window)
    {
        var position = Tools.handlePosition;

        EditorGUI.BeginChangeCheck();

        var result = Handles.PositionHandle(position, Quaternion.identity);

        if (EditorGUI.EndChangeCheck())
        {
            var delta = result - position;

            Undo.RecordObjects(Selection.transforms, "Move Lights");

            foreach (var light in targets)
                ((Light)light).transform.position += delta;
        }
    }

    // OnDrawHandles is called when a custom editor tool is available for the current selection. Use this to draw
    // information in the SceneView when any object matching the target type is selected.
    public void OnDrawHandles()
    {
        foreach (var light in targets)
        {
            // If the Light Tool is active, draw a green radius handle. If it is not active, make the radius blue.
            Handles.color = EditorTools.IsActiveTool(this) ? Color.green : Color.blue;
            Handles.RadiusHandle(Quaternion.identity, ((Light)light).transform.position, 2f);
            Handles.color = Color.white;
        }
    }
}