"We offer new support options and therefor the forums are now in read-only mode! Please check out our Support Center for more information." - Vuforia Engine Team

Wrong FOV on iPad 4

By zambezi on Tue, 12/09/2014 - 08:57

Vuforia SDK Version: Unity 3.0.9.2 -Description with steps to reproduce:

We are building an augmented app, in which some real-world Objects (a city) are precicely overlayed by some virtual content. We recently upgraded to Vuforia 3.0.9.2. Now everything worked fine when running the App on Ipad air, however on Ipad 4 the virtual objects do not match up perfectly (the farer away from the center/the marker, the worse). It seems like the vuforia camera is using a wrong Field of View, so that everything gets "distorted".

It's kind of hard to see the effect without a detailed real-life Scene on which the augmented stuff is projected, however it can be seen by taking a mid-sized cardboard box, measure it and recreate it in Unity and place an Image-Marker on the front. Now in Ipad Air the virtual Cube should somehow cover the real box, where on ipad 4 it does not align properly. Unfortunately i do not have the real-world city right here, but i made a demo project as described above, and although it does not align perfectly and is just a very rough setup, you can see the difference Ipad air/Ipad 4. I don't have any other stuff in the scene, just the cube and the Vuforia Plugin. 

 

"Correct" Ipad Air:

[IMG]http://i58.tinypic.com/2w4n0xh.png[/IMG]

 

"Bad" Ipad 4:

 

[IMG]http://i59.tinypic.com/21j6h39.png[/IMG]

 

By downgrading to an older Unity Version and Vuforia 2.8 everything was back to normal again.

-Development OS (Mac OS X, Windows, Linux): Mac OSX -Mobile OS and Version: IOS 7.1 -Mobile Device Manufacturer and Model name: Ipad air/Ipad 4 -Do the Vuforia Sample Applications show the same behavior?:

Thanks for reporting the issue. I just tried the Unity Multi Target Sample app on iPad 4 and iPad Air and there is no noticeable offset like the way you are seeing it. Can you download the multi target sample app and try it on your iPad4/iPad Air. Let us know how it goes.

AlessandroB

Mon, 10/06/2014 - 19:15

Permalink

Is this happening in Landscape mode ? (it appears so from the screenshot, unless you have cropped them,.... please confirm).

 

Yes, this happens in landscape mode - our application is clamped in landscape right. I am downloading the multitarget example right now, but i could imagine that you won't see it on the small cube of the example - the offset/distortion is best seen on objects far away from the marker/center.

Ca you share the exact details on how to reproduce it, i.e.:

- what are the image target size as specified in the XML dataset file

- are you changing the target size at runtime via any script ?

- what are the image target size as specified in the XML dataset file

Copied from the xml: 75.01002 width, 189.980179 height. Representing a 7.5 * 19 cm big Real-World Marker.

- are you changing the target size at runtime via any script ?

Could you share one or two screenshots showing the cube placed on the target in your Unity scene ?

Also, one thing not fully clear is the mismatch between the box size:

Will close this due to lack of feedback.

If you need to update this, please create a new thread and post a link to this thread for reference.