BabylonNative - Is it possible to restart an Android activity?

Eric_Beets · September 7, 2021, 10:01am

Indeed onDestroy is called, but the question is how to properly stop XR?

Cedric · September 7, 2021, 10:05am

something like mView.eval("exitAR();", "ActivityScript");
where exitAR is a JS function defined in experience.js

Eric_Beets · September 7, 2021, 10:11am

Ohh interesting, I was trying to stop XR in the native C ++ part and not in the JS part … that’s probably what I was doing wrong …
I’m trying this this afternoon

Cedric · September 7, 2021, 10:13am

I’m trying to make it work on my side. destruction is async, might need some await or something to make it work.

my function is :


function exitAR()
{
    if (currentXR) {
        console.log("Exiting XR");
        currentXR.baseExperience.exitXRAsync();
        currentXR = null;
    }
}

and currentXR is assigned with xr just after enterXRAsync call

Eric_Beets · September 7, 2021, 11:45am

I still have an issue when g_graphics tried to be released (forcing g_graphics.reset(); when activity is destroying or when si restarting …)…

Cedric · September 7, 2021, 1:22pm

I’m still investigating with another idea…

Cedric · September 8, 2021, 1:46pm

It’s an opengl context switching issue. At some point, a (new?) context is bound for the thread but I find no call to make it current. This newly bound context is not the expected one. Still searching …

Eric_Beets · September 8, 2021, 2:27pm

Don’t hesitate to let me know if I can help you somewhere …

Cedric · September 9, 2021, 9:36am

I’m still debugging today. At this stage, I didn’t figure out what is changing the GL context on the BN side. My guess is with Surface/View life cycle, the system destroys something that change the GL Context. I tried wo unbind the current GL context on the Java side in the surfaceDestroyed callback without much luck.
Today, I’ll try to put a breakpoint in eglMakeCurrent to see if anything calls it. And I’ll also try with RenderDoc to see if I get better logs.

Cedric · September 10, 2021, 8:38am

No stacktrace with lldb/AndroidStudio. RenderDoc doesn’t hook on the app (might be my configuration in this case).
I still believe the Android system does something when XR view is destroyed. I’ll try now to do a minimal repro wihtin XR: keep view management but do not re-create surface in XR.cpp

Cedric · September 10, 2021, 9:08am

I removed xrSurfaceView from BabylonView.java. No view = no surface for XR = no rendering and there is still a context issue. So, it’s might not be related to the surface, I leasst not the way I imagined it. Next on the list is XR resources initialization. Now I’ll disable nativeXR code until it works !

Cedric · September 10, 2021, 1:08pm

I’m removing more and more code. Crash still occurs with same wrong GL context.
Surface is now never changed. No rendering code in XR.cpp and less rendering code in NativeXR.cpp
I’m starting to wonder if it might be related to ARCore.
@Eric_Beets Can you please try to use a more recent version ? Changing the versison in the following lines should do the trick :

github.com

BabylonJS/BabylonNative/blob/a89ba66567c4ceedaa2e3dc867da4646b99f161a/Apps/Playground/Android/app/build.gradle#L75

    
      
              externalNativeBuild {
                  cmake {
                      version '3.19.0+'
                      path 'CMakeLists.txt'
                  }
              }
          }
          
          
dependencies {
              // ARCore library
              implementation 'com.google.ar:core:1.14.0'
              natives 'com.google.ar:core:1.14.0'
          
          
    implementation 'com.android.support:appcompat-v7:27.1.1'
              implementation 'com.android.support:design:27.1.1'
          }
          
          
// Extracts the shared libraries from aars in the natives configuration.
          // This is done so that NDK builds can access these libraries.
          task extractNativeLibraries() {
              // Always extract, this insures the native libs are updated if the version changes.

Eric_Beets · September 10, 2021, 3:58pm

I think that I have already tried it, I just re-test, and still a crash.
But I also have the feeling it come from the ARCore, some resources are not released/close or something like that …

Cedric · September 10, 2021, 4:03pm

yes, I’ve update the issue on GitHub:

github.com/BabylonJS/BabylonNative

[Android] Restart Activity with XR

opened 02:53PM - 07 Sep 21 UTC

CedricGuillemet

Follow up https://forum.babylonjs.com/t/babylonnative-is-it-possible-to-restart-…an-android-activity/23542/24 **Describe the bug** Crash second time launching the playground activity when XR was active the first time. **To Reproduce** Steps to reproduce the behavior: 1. Clone this blanch https://github.com/EricBeetsOfficial-Opuscope/BabylonNative/tree/test/Android_lifecycle_activities 2. Build & run for Android 3. tap button 'Launch Playground' 4. wait for XR to be active 5. Get back to main activity 6. tap again 'Launch Playground' **Expected behavior** No crash **Other** - Android Only. ViewController life management is different on iOS.

Cedric · September 13, 2021, 12:52pm

Doing a bit of progress: Binding opengl context only and not the surface make it not crash in later use of the context.

EGLDisplay previousDisplay{ eglGetDisplay(EGL_DEFAULT_DISPLAY) };
EGLSurface previousDrawSurface{ eglGetCurrentSurface(EGL_DRAW) };
EGLSurface previousReadSurface{ eglGetCurrentSurface(EGL_READ) };
EGLContext previousContext{ eglGetCurrentContext() };
eglMakeCurrent(eglGetDisplay(EGL_DEFAULT_DISPLAY), EGL_NO_SURFACE, EGL_NO_SURFACE, previousContext);
ArSession_update(xrContext->Session, xrContext->Frame);
eglMakeCurrent(previousDisplay, previousDrawSurface, previousReadSurface, previousContext);

Now, there are a bunch of issues with engine destruction/re-initialization…

Cedric · September 13, 2021, 12:59pm

@Eric_Beets

I’ve opened a PR on your branch, can you test it please?

Eric_Beets · September 13, 2021, 4:48pm

I just tested the, it crashes to renderer_gl.h:1338

With the following stack:

2021-09-13 18:46:26.662 21920-22035/com.android.babylonnative.playground I/BabylonNative: BJS - [18:46:26]: FPS: Infinity
2021-09-13 18:46:47.522 21920-22095/com.android.babylonnative.playground E/native: E0913 18:46:47.522607   22095 camera_image_stream.cc:271] FAILED_PRECONDITION: Failed to extract the native metadata, status=DEADLINE_EXCEEDED: Timed out waiting for metadata.
    === Source Location Trace: ===
    third_party/arcore/ar/camera/android/metadata_cache.cc:53
    third_party/arcore/ar/camera/android/metadata_extraction.cc:54
    
    === Source Location Trace: ===
    third_party/arcore/ar/camera/android/camera_image_stream.cc:205
2021-09-13 18:46:57.905 21920-22095/com.android.babylonnative.playground E/native: E0913 18:46:57.905314   22095 camera_image_stream.cc:271] FAILED_PRECONDITION: Failed to extract the native metadata, status=DEADLINE_EXCEEDED: Timed out waiting for metadata.
    === Source Location Trace: ===
    third_party/arcore/ar/camera/android/metadata_cache.cc:53
    third_party/arcore/ar/camera/android/metadata_extraction.cc:54
    
    === Source Location Trace: ===
    third_party/arcore/ar/camera/android/camera_image_stream.cc:205
2021-09-13 18:46:57.906 21920-22095/com.android.babylonnative.playground E/native: E0913 18:46:57.906103   22095 camera_image_stream.cc:232] Camera Image Stream failed to dequeue Image from ImageReader. status=UNAVAILABLE: AImageReader_acquireLatestImage [type.googleapis.com/util.ErrorSpacePayload='ImageReaderStatusErrorSpaceClass::AMEDIA_IMGREADER_NO_BUFFER_AVAILABLE']
    === Source Location Trace: ===
    third_party/arcore/ar/camera/android/imagereader_status_error_space.cc:112
    third_party/arcore/ar/camera/android/imagereader_ndk_wrapper.cc:241
     acquired_image_count=3
2021-09-13 18:47:14.422 21920-21941/com.android.babylonnative.playground E/ACameraDevice: Frame number out of order. Expect 5 but get 10
2021-09-13 18:47:21.402 21920-22095/com.android.babylonnative.playground E/native: E0913 18:47:21.402012   22095 camera_image_stream.cc:271] FAILED_PRECONDITION: Failed to extract the native metadata, status=DEADLINE_EXCEEDED: Timed out waiting for metadata.
    === Source Location Trace: ===
    third_party/arcore/ar/camera/android/metadata_cache.cc:53
    third_party/arcore/ar/camera/android/metadata_extraction.cc:54

Cedric · September 14, 2021, 11:55am

I moved engine shutdown in main activity. I get no more crash with multiple back and forth between main & playground activities.
PR is in sync with my latest changes.

Eric_Beets · September 14, 2021, 2:30pm

I just tried it on S8+ and S9+, and it still crashes …
I tested it on a Xiaomi MiA3, the app does not crash, but when I restart the AR activity, the default box is not in the scene.
Is there something particular on Samsung devices ?

Cedric · September 14, 2021, 2:42pm

yes, we faced some issues with Samsung. Like this one : AR view broken on Samsung SM-T820 · Issue #788 · BabylonJS/BabylonNative · GitHub
Let me take a look for the default box.

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BabylonNative - Is it possible to restart an Android activity?

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