Extreme lag and black screen

June 9, 2015 - 6:54am #1

Using Unity 5.0.2p4 and Vuforia 4.2.3 on iOS.

Building with IL2CPP and Universal architecture.

The app runs fine on iPhone5 32bit but running on iPhone6 64bit, it runs until the ARCamera comes in.

Then the whole app is really laggy. Here are the issues I get:

- Cam feed is black screen though it does track as it gets the marker. So the object appears on balck screen.

- The whole app runs extremely slow, I have a UI element reporting the orientation of the device and the rotation instead of being done each frame goes once per second (approximately).  The app runs fine once I quit the AR mode. The whole UI is actually slow as I have other items and I can see that pressing them, the action happens late.


I checked the log from xCode and it does not show anything unusual, I attached the log if that may help.


Thanks already.

Plain text icon logVuforia.txt82.17 KB

Extreme lag and black screen

March 9, 2016 - 10:50am #5

UPDATE: Vuforia 5.5.9 has been released and supports the METAL Graphics API on iOS:



Also, make sure to check the Unity Migration Guide before upgrading to Vuforia 5.5:


Extreme lag and black screen

June 11, 2015 - 10:59pm #4

Just an additional tip for anyone using Unity 5.0.1 or 5.0.2 in this thread;

Unity 5.0.1 and 5.0.2 were affected by a UI rendering issue that was appearing with Vuforia 4.2.3, which has been discussed here:


That issue has been resolved in Unity 5.0.3 ;

of course, the OpenGL ES 2.0 player settings is still required as Metal is not supported by Vuforia 4.2 yet.

Extreme lag and black screen

June 11, 2015 - 7:39am #3

Thank you so much i was struggling with this bug for 2 days and the deadline was approching :))

Extreme lag and black screen

June 11, 2015 - 3:39am #2
The black screen issue affects currently Unity 5.0 - 5.1 and Vuforia 4.x.
Currently Vuforia seems to have problems with the iOS Metal API (which is auto selected on x64 device), to fix this issue:
In Unity goto "Build settings -> iOS" and click "Player Settings".
Now the Player Settings Panel should be opened on the right side.
Select the Tab "Other Settings" and set the option "Graphics API" to "Open GL ES 2.0".
This fixes the black screen issue for me on Mac OS 10.10 + Unity 5.x.
Hope that helps ;)
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