写一个unity c#脚本，实现屏幕中央准星放到物体上时显示一个panel，其显示物体的各种信息，准星离开后关闭panel

在Unity中，你可以通过C#编写如下的Mecanim或Input Manager脚本来实现这个功能。这里假设我们已经有了一个UI面板（GameObject）`uiPanel`，并且物体的信息已经封装在一个`ObjectInfo`类中：

using UnityEngine;
using UnityEngine.UI;

public class AimAndPanel : MonoBehaviour
{
    // UI Panel reference
    public GameObject uiPanel;
    
    // ObjectInfo class (replace with your actual implementation)
    private ObjectInfo objectInfo;

    // Camera reference for screen center aiming
    private Camera mainCamera;

    void Start()
    {
        mainCamera = Camera.main;
        objectInfo = GetComponent<ObjectInfo>(); // Assuming the info is attached to this script
    }

    void Update()
    {
        // Check if cursor or aim point is near the center of the screen
        Vector3 mousePosition = Input.mousePosition;
        float mouseXToScreenCenterX = (mainCamera.ViewportToWorldPoint(mousePosition).x - mainCamera.ViewportToWorldPoint(new Vector3(0.5f, 0.5f)).x);
        float mouseXToScreenCenterY = (mainCamera.ViewportToWorldPoint(mousePosition).y - mainCamera.ViewportToWorldPoint(new Vector3(0.5f, 0.5f)).y);

        // Use a tolerance value (e.g., 5 pixels) for proximity check
        const float tolerance = 5f;
        if (Mathf.Abs(mouseXToScreenCenterX) < tolerance && Mathf.Abs(mouseXToScreenCenterY) < tolerance)
        {
            ShowPanel(objectInfo); // Display panel with object info
        }
        else
        {
            HidePanel(); // Close the panel when not aimed at center
        }
    }

    private void ShowPanel(ObjectInfo objInfo)
    {
        uiPanel.SetActive(true);
        // Set the UI panel's content with objectInfo data
        Text text = uiPanel.GetComponent<Text>();
        text.text = "Object Info:\n" + objInfo.ToString();
    }

    private void HidePanel()
    {
        uiPanel.SetActive(false);
    }
}

// Example usage: Place an ObjectInfo component on the game object you want to display info about
[Serializable]
public class ObjectInfo
{
    // Add properties here like name, position, etc.
    public string Name { get; set; }
    public Vector3 Position { get; set; }

    // Override ToString() method for clean output in the UI
    public override string ToString()
    {
        return $"Name: {Name}, Position: ({Position.x}, {Position.y})";
    }
}