编辑器下实现Update

    private void OnEnable() {
        if (Application.isEditor) {
            SceneView.onSceneGUIDelegate += OnScene;
        }
    }

    private void OnScene(SceneView sceneview) {
        if (isBursh)
        {
            Ray ray = HandleUtility.GUIPointToWorldRay(Event.current.mousePosition);// 从鼠标位置发射射线

            RaycastHit hit; // 用于存储射线碰撞的信息

            if (Physics.Raycast(ray, out hit))
            {
                Vector3 worldPoint = hit.point; // 获取碰撞点的世界坐标
                //Debug.Log("鼠标点击的世界坐标: " + worldPoint);
                brush.position = worldPoint;
            }
        }

        if (Event.current.type == EventType.KeyDown && Event.current.keyCode == KeyCode.Escape) {
            isBursh = !isBursh;
        }
    }