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This article explains how to determine if a game object is visible in both Scene view and Game view using a camera. The content includes practical code examples and usage methods for the isVisible, OnBecameVisible, and OnBecameInvisible components.

Determining Object Visibility in Scene and Game Views

When working with Unity, you may need to check whether a specific game object is visible in the current scene's camera view. This can be useful for various applications, such as optimizing rendering performance or updating game elements based on visibility.

Basics of isVisible Usage

Before diving into the code examples, it's essential to understand how the isVisible method works. This method is only available on a MeshRenderer component. Without the MeshRenderer component, calling isVisible will return null, and using the method in this case could lead to errors.

The process of checking visibility using isVisible involves:

Code Example for isVisible

Here's a practical example of how to use the isVisible method:

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class CameraCube : MonoBehaviour
{
    public GameObject[] go_array; // Array of game objects to check
    private void Update()
    {
        UpdateArray();
    }
    void UpdateArray()
    {
        for (int i = 0; i < go_array.length; i++)
        {
            if (go_array[i] != null && go_array[i].GetComponent
   
    () != null)
            {
                Debug.Log(go_array[i].name + "     isVisible:" + go_array[i].GetComponent
    
     ().isVisible);
            }
        }
    }
}
    
   

This script iterates over an array of game objects, checking each one's visibility status in the current camera view. The Update method calls UpdateArray(), which applies the visibility check in every frame.

Understanding OnBecameVisible and OnBecameInvisible

The OnBecameVisible and OnBecameInvisible events are used to trigger specific actions when a game object enters or exits a camera's visible area. These events are especially useful for responsive UI elements or dynamic gameplay interactions.

Usage of OnBecameVisible and OnBecameInvisible

Here's a simple example of how to use OnBecameVisible and OnBecameInvisible:

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class VisibleOrInvisible : MonoBehaviour
{
    private void OnBecameVisible()
    {
        Debug.Log("Object has entered the camera view");
    }
    private void OnBecameInvisible()
    {
        Debug.Log("Object has exited the camera view");
    }
}

This script uses the OnBecameVisible and OnBecameInvisible events to log messages when the attached game object is added to or removed from the camera's view. The script can be attached to any object to monitor its visibility state.

Mounting Components to 3D Objects

To use the above methods effectively, ensure that the necessary components are attached to the right game objects. For the isVisible method, the MeshRenderer component must be present on the target object. For event handlers like OnBecameVisible, use them appropriately based on your game's requirements.

Further Reading

For more details on Unity's isVisible, OnBecameVisible, and OnBecameInvisible methods, refer to Unity's official documentation or explore additional resources available online. These resources will provide in-depth explanations and use cases for each component and method.

Conclusion

By utilizing these methods, you can efficiently determine the visibility of game objects in different Unity views and react to visibility changes as needed for your project's requirements.