ARCore 会话未重新启动

Question

Using Google ARCore, when I am in the game I have built I have a restart button to clear the scene and restart the level. I was doing this by reloading the scene using Scenemanager.LoadScene() , however when the scene reloads the camera is not initialised and just shows a blue screen with my UI over the top.

Is there something I can use in code to ensure this doesn't happen when reloading the scene?

Answer 1

In ARCore NDK you'd use the following method for destroying a session and releasing its resources:

void ArSession_destroy(
    ArSession *session
)

This method releases resources used by an ARCore session. It'll take several seconds to complete. To prevent blocking the main thread, call ArSession_pause() on the main thread , and then call ArSession_destroy() on a background thread .

Then, you have to create a new session with :

ArSession_create()

Also, in ARCore Android , there's typically onPause() and onResume() methods for current session . But I use 2 other ones: pause() for pausing the current session and resume() for starting or resuming the ARCore current session.

In Unity you should try DestroyImmediate(session) or Destroy(session) for your purpose.

ARCoreSession session = goARCoreDevice.GetComponent<ARCoreSession>();
ARCoreSessionConfig myConfig = session.SessionConfig;
DestroyImmediate(session);
// Destroy(session);
yield return null;
session = goARCoreDevice.AddComponent<ARCoreSession>();
session.SessionConfig = myConfig;
session.enabled = true;

Hope this helps.

Answer 2

For those who have an issue with ARCore in android studio, to solve this I used the simple workaround of replacing fragment instead of restarting entire Activity.

Procedure: I'm adding ArFragment dynamically and when the user press on refresh button I'm replacing the entire fragment.

1-Adding Fragment dynamically:

getSupportFragmentManager()
                .beginTransaction()
                .add(R.id.container, new MainARFragment())
                .addToBackStack(null)
                .commit();

2-Here is my refresh button code:

 refreshButton.setOnClickListener(view -> {
            //refresh everything remove models and detect from start
            getSupportFragmentManager().beginTransaction()
                    .replace(R.id.container, new MainARFragment()).commit();
        });

Everything worked fine but when I tried to findFragmentById after adding it inside onCreate method I got null pointer exception. To avoid this use Callback from ArFragment and in onAttach of ArFragment call the onComplete method and then use :

arFragment = (MainARFragment) getSupportFragmentManager().findFragmentById(R.id.container);

Hope this will help.

Answer 3

@Nouman Ch
According to your method, the fragment was successfully replaced, but I encountered a new problem. the onupdatelistener was not updated, and the camera posture could not be obtained after restarting the session. How do you understand the sentence "please use callback in arfragment" in your answer? I don't know how to use it. i asked the questin in stackflow ,but nobody answered to me . click here to get the detail