EasyAR 3 issues with 'Center Target' option

Question

Hello together,

we´ve upgraded our unity app from EasyAR 2 to EasyAR 3 due to the 64 Bit requriments for google.

We have noticed that the option ‚First Target‘ for ‚Center Target‘ option makes the tracking really ‚floating / slippery‘. With the option ‚Camera‘ the tracking works quiet well.

Unfortunately, our AR content makes it neccessary to use the ‚First Target‘ option, cause we are use particle systems, splines, etc.

To reproduce (EasyAR 3.0.0 and 3.0.1):

• Open sample scene „HelloAR_ImageTarget“
• Test tracking with sample marker ‚namecard‘
• Change ‚Center Target‘ on ‚ImageTrackerBehaviour‘ from ‚Camera‘ to ‚FirstTarget‘
• Test again and notice that the mapped content now is slidng on the marker

Is it caused by a wrong setup? Or can you confirm that this is a known issue?

Any help would be appreciated.

Best regards

Florian

Answer 1

The EasyAR considers the transforms(either camera or first target) be aligned at the 'center' of the unity world coordinate(Vector3(0,0,0) and Quaternion.identity). As long as the markers or camera is aligned to it, it will work fine. But once they are offset and rotated, it won't going to work.

I think EasyAR team should fix the `SetMatrixOnTransform(Transform, Matrix4x4)` method in `Utility.cs` so that it will compensate the target position and orientation in the world. This will affect the `ImageTrackerBehaviour.cs` also, so many parts should be fixed.

Comments

Thank you for your advice. We have rewrite all the scripts and I believe all those parts you mentioned have gone.

Answer 2

The bug has been fixed in version 4. A upgrade version of version 3 is on the way.

Comments

When will release the upgrade version of 3??

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Very soon. I will update here when it's out.

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Version 3.1 is online now. You can find it from <previous versions> on download page.

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But still have same problem in Easyar 3.1..the single target perfectly fit for first target option..when I use more than one target the models are keep rotating and shaking...is there any way to use this please help me ...

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The original question has been fixed.
The shaking is also there if you use camera center. There is no difference except who shakes (the camera or the target). When you use multiple targets, there is only one object (one of the targets or the camera) stay, all other objects will move when the image or the camera device moves. The shake is caused by unstable tracking, but it will not make things unusable in most cases.
And as you mentioned the model keep rotating, do you mean rotate like a planet? If so, there should be something wrong. It is better to provide some videos so that we can understand what is happening,

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You see target first time tracking models transformation are good..but when I move to out of focus then focus to target the model rotation and position are diff.....I think navmesh agent problem in multi target....if I don't use navmesh function multi target working really good........is there any chance to resolve this???

Video link:

https://drive.google.com/file/d/1TVbIIOys5DrZgFeApwMkB9ykY9zyGhTc/view?usp=drivesdk