Image Tracking - Detect a tracked image only for the first time, then ignore it

[devrandomzero]

Hi,
I would like to ignore an image in the library after its first detection.
I looked in the documentation/forum and it seems that it’s not possible to remove an image in the reference image library.
Should I track for example all the referenceImage.name in a list (adding their names when first detected) and, in case of being detected again, check if they are already present inside?

Do you have a better suggestion/solution?

Thank you

Bye

[andyb-unity]

Hi @devrandomzero ,

You are correct that AR Foundation does not provide an interface for removing reference images from a reference image library at runtime.

Your proposed solution sounds like it would work! I might recommend using a HashSet (HashSet<T> Class (System.Collections.Generic) | Microsoft Learn) instead of a List, as HashSets provide constant-time lookup to see if the set contains an element.

[devrandomzero]

@andyb-unity

Hi @devrandomzero ,

You are correct that AR Foundation does not provide an interface for removing reference images from a reference image library at runtime.

Your proposed solution sounds like it would work! I might recommend using a HashSet (https://docs.microsoft.com/en-us/dotnet/api/system.collections.generic.hashset-1?view=net-6.0) instead of a List, as HashSets provide constant-time lookup to see if the set contains an element.

Andy thank you for answering me, I implemented my original solution using an hashset instead of a list and everything is working correctly.

I think it would be cool in the future to have the option to remove one or more images at runtime but for now I’ll manage.

Thank you again

Bye