Hello @magglemitch,

I responded here: https://developer.vuforia.com/forum/ios/resolution-vuforia-7-ios-113-black-screen-problem#comment-67121

Thanks,

Vuforia Engine Support

Any solutions yet? Or are we forced to use OpenGLES still?

I also discovered that if the Canvas objects are disabled while Vuforia is active, Vuforia still works. We have an app that seemed to start exhibiting the black camera screen on certain model iOS devices after the iOS 11.3.1 update (not sure about this though). Luckily in this app, only a single button was required while Vuforia was active.

I disabled all canvas game objects while Vuforia is active. And I replaced the one canvas used as an overlay with Vuforia with a fake canvas parented under the camera for which I wrote a layout script, and a fake button that used a mesh and a Collider2D quad. Then Vuforia started working again. Hope this idea helps someone.

This app was built with Unity 2017.3.1f1, and the XCode 9.2 and iOS 11.3 workaround that has been discussed here previously. 

Hi,

We were using 9.4 beta to see if it resolved the issue. It does not. We see the issue in XCode 9.3 (Release version) as well.

As far as I can see this issue exists when Auto Graphics API (or Metal) is selected in the player settings. 

Building and running on an ARKIt capable device will give a black screen instead of the usual video background. It appears to behave normally when running in the Unity editor.

The following is our configuration :

• Unity 2018.1.0f2
• ARKit 1.5
• Vuforia 7.1.34

For completeness, a list of ARKit compatible devices is given below. I would expect to see the issue only on these devices running iOS 11.3+ with the "Auto graphics API" or Metal selected when the build is done in Unity.

I will also attach some screenshots showing a couple of the components and settings we are using in our project.

Regards,

Kevin

----------------------------

iPhone X

iPhone 8

iPhone 8 Plus

iPhone 7

iPhone 7 Plus

iPhone 6s

iPhone 6s Plus

iPhone SE

iPad Pro (12.9-inch) Wi-Fi

iPad Pro (12.9-inch) Wi-Fi + Cellular

iPad Pro (9.7-inch) Wi-Fi

iPad Pro (9.7-inch) Wi-Fi + Cellular

iPad Pro 12.9-inch (2nd generation) Wi-Fi

iPad Pro 12.9-inch (2nd generation) Wi-Fi + Cellular

iPad Pro (10.5-inch) Wi-Fi

iPad Pro (10.5-inch) Wi-Fi + Cellular

iPad (5th generation) Wi-Fi

iPad (5th generation) Wi-Fi + Cellular

HoughtonMifflinHarcourt wrote:

Hi,

 

Is there a timeline on a fix for the issue of the video background not rendering on iOS 11.3 with Vuforia 7.1.34 + ARKit. 

The issue is still present with Unity 2018.1.0f2 and Xcode 9.3 Release/XCode beta 9.4.

We are currently trying to push out new releases of an app and are blocked with this issue.

For info the logs are showing the message "VideoBackgroundConfig with screen size of zero received, skipping config step".

 

Thanks

Kevin Moroney

Hello Kevin,

Is there a reason you are using XCode 9.4 beta? Do you get this same issue with 9.3? Are you seeing this on all devices? We haven't been able to reproduce this issue yet.

Thanks,

Vuforia Support

OpenGLES 2/3 is only a workaround for the issue in certain cases.

If you need to use the Metal Graphics API I still have not found a solution.

Change graphics API from Metal (or automatic) to GLES 3.0 or GLES 2.0

Have anyone find a Solution for this?

HoughtonMifflinHarcourt wrote:

Same here, however bringing more components into the scene along with ARKit seems to break it. I have a hunch that the Metal framework required by ARKit is the root cause of an incompatibility somewhere. When running only under only GLES2.0 the issue disappears. However in our case seeing as we need to have ARKit included there is no way around having the Metal framework available. I also had a look at whether the Canvas component could be causing the "VideoBackgroundConfig with screen size of zero received, skipping config step" issue during a resizing step, but this seems to work in isolation which leads back to Metal being the cause.

If anyone from Vuforia could enlighten us and give a timeline for a fix that would be great.

 

Kevin 

Amen to this , was looking at our logs and wondering why there were issues with us having a Canvas in the scene (even just an empty canvas) but it would work without it.



Will try making the graphics API GLES2.0 only to get around this issue now as it seems like such an easy fix to the problem. Logs below - I will try to raise this to both Unity and Vuforia developers as bugs like this should surely be caught before releases or vital patches are released.



Logs that highlighted the issue to me:



Setting up 1 worker threads for Enlighten.

Thread -> id: 17174f000 -> priority: 1

2018-05-11 08:53:50.404819+0100 gymsharkdemo[283:10028] DEBUG/AR(283) UIView has CAMetalLayer layer class

2018-05-11 08:53:50.405214+0100 gymsharkdemo[283:10028] DEBUG/AR(283) UIView does not respond to selector renderFrameVuforia

2018-05-11 08:53:50.405349+0100 gymsharkdemo[283:10028] DEBUG/AR(283) UIView has CAMetalLayer layer class

2018-05-11 08:53:50.405389+0100 gymsharkdemo[283:10028] DEBUG/AR(283) UIView does not respond to selector renderFrameVuforia

2018-05-11 08:53:50.405422+0100 gymsharkdemo[283:10028] DEBUG/AR(283) Could not find a UIView with CAEAGLLayer or CAMetalLayer layer class that responds to selector renderFrameVuforia

Same here, however bringing more components into the scene along with ARKit seems to break it. I have a hunch that the Metal framework required by ARKit is the root cause of an incompatibility somewhere. When running only under only GLES2.0 the issue disappears. However in our case seeing as we need to have ARKit included there is no way around having the Metal framework available. I also had a look at whether the Canvas component could be causing the "VideoBackgroundConfig with screen size of zero received, skipping config step" issue during a resizing step, but this seems to work in isolation which leads back to Metal being the cause.

If anyone from Vuforia could enlighten us and give a timeline for a fix that would be great.

Kevin 

HoughtonMifflinHarcourt wrote:

Hi,

 

Is there a timeline on a fix for the issue of the video background not rendering on iOS 11.3 with Vuforia 7.1.34 + ARKit. 

The issue is still present with Unity 2018.1.0f2 and Xcode 9.3 Release/XCode beta 9.4.

We are currently trying to push out new releases of an app and are blocked with this issue.

For info the logs are showing the message "VideoBackgroundConfig with screen size of zero received, skipping config step".

 

Thanks

Kevin Moroney

Having a very similar issue here.. we have noticed after patching Vuforia to 7.1.34 and using unity 2018.1.0f1 that if we make a new blank scene and just add the vuforia camera and marker again.. suddenly the camera works? Are working through the process of adding everything from the other scenes to the new bank scene now to see if it all still works.. I have a hunch that there is some conflict going on with the unity UI system in our original scene but it will require further investigation.. spent all day looking into fixing this issue.