Bug MARS misplacing elements

hello @ricardotipz,

Strange, Can you also add a

TrackingStateCondition

to the image marker and set it to "

Tracking

" to be able to remove the gameobjects when lost and see if the objects get anchored correctly?

 

hello @ricardotipz,

Even more strange; Does it work on the simulator?; could you share with us your stack trace to see whats going on?.

Lets try something simpler; an image with a cube/sphere/any mesh. If you follow this: https://docs.unity3d.com/Packages/com.unity.mars@1.3/manual/Markers.html can you get a basic image marker track?

 

Well since the ARCommon gameobject is not attached to anything it will appear in the space, depending on where SLAM starts to track and sets the initial position.

With regards to stack trace on android, you will have to do it with ADB Logcat https://answers.unity.com/questions/492681/how-to-use-adb-logcat.html

 

hello @ricardotipz,

If you checked your logs, seems you are having a null reference exception

Code (CSharp):

1. 06-07 16:11:52.808 20215 20324 E Unity   : ArgumentException: Index out of bounds.
2. 06-07 16:11:52.808 20215 20324 E Unity   :   at (wrapper managed-to-native) UnityEngine.Input.GetTouch_Injected(int,UnityEngine.Touch&)
3. 06-07 16:11:52.808 20215 20324 E Unity   :   at UnityEngine.Input.GetTouch (System.Int32 index) [0x00000] in <e77348f842b441a984e2e95edba2a91d>:0
4. 06-07 16:11:52.808 20215 20324 E Unity   :   at OnTouchScreen.Update () [0x00001] in D:\UnityProjects\EpixARURPv2\Assets\Scripts\OnTouchScreen.cs:26

This might be preventing the logic of the image markers work properly. We are trying to diagnose if you have a problem with Image Markers; could you create a new empty project with just an image marker proxy and a cube for it like its mentioned in the docs?

This is to diagnose for errors on the ImageMarker's side.

 

Hi @Ricardotlpz! Sorry to hear that you're having trouble.

What you just described is normal behavior. The color of the diamond is based on a serialized field in the Proxy class, which means that if you duplicate a proxy, it will have the same color diamond. When you create a _new_ proxy with the Image Marker button, we assign a random color to each one for convenience.

Looking at the log you shared, I see the following:

ARTrackedImageManager 'AR Session' was enabled but no reference image library is specified. To enable, set a valid reference image library and then re-enable this component.

This seems to indicate that something is wrong setting up the reference image library. Do you have one set up on the MARSSession in the scene you are loading? I think this should be required for simulation, but it may not be.

If you _do_ have a library set up, this is a bug. If you are able to do so, please submit your project through the Unity Bug Reporter (in the menu, Help > Report a Bug...) and share your case number. This will help us replicate the issue on our end and figure out what's going wrong.

 

Yep! I see it. Case # is 1341952.

I'm downloading your project now and hopefully we'll be able to come back with a fix or a workaround.

 

Hi there. I was able to build your project, and I think I see what you were seeing, but I did eventually get the image to track. I'm sorry to say it, but I think the images you are using for tracking just don't have enough valid fiducial markers for good image tracking. But! This is relatively easily fixed. You can keep the content you have as long as you build out more high-variance detail along the border, or in "chunks" within the image. Something like a QR code is the quintessential image marker because it is entirely black-and-white corners. These make great fiducial markers, and give you good, reliable tracking. I have seen apps get creative with blocky patterns, different shapes like triangles or diamonds, etc.

Edit: My bad... According to Google's advice, a QR code is not a good image marker, but I think the logic still applies--you need some more areas with high-frequency detail to get a better tracking score.

In order to make sure we're on the right track, please try making a build using the included image markers in the MARS sample content under Assets/MARS/Content/Shared/Textures. I tried a build with these in the marker library instead of your custom images, and the tracking worked much better. Let us know if this works for you, and whether you are able to get better tracking out of your custom image markers with added fiducials. Google has some advice for how to choose good images, and instructions for how to use their `arcoreimg` utility to get a score for your images as you iterate on them.

Hope this helps!

 

That's pretty strange. Can you describe when you started and what may have changed? When you say "the same ones you used" are you referring to the MARS sample images or the ones that you were using in the project you shared? Were you using MARS the whole time, or did you start with AR Foundation and then try MARS? Did you upgrade your Unity version and/or package versions? When you compare with UE4, do you see any configuration differences like the maximum number of moving images? Something I tried when I was troubleshooting was to check "specify size" for the images in the library, which I think helps improve tracking quality.

I can sympathize. Computer vision adds a lot of uncertainty to what is going on, making it harder to identify and fix bugs. It could be things like time of day affecting the lighting or introducing motion blur to the camera feed, or a huge number of subtle differences from one test to the next. In order for us to try and fix the issue we need to know as much as we can about what might have changed between earlier, when thing were working well, and now.

We will continue to investigate the issue on our end. It is especially helpful to have a real-world example, so thank you for sharing. We'll share any insights we find and if there's a bug on our end we'll fix it!

 

Thanks for the info! I'll keep you posted as we explore this issue further.