AssetBundels builds in between Unity versions

Hi,

It seems that the AssetBundles files holds Unity version inside them on the first line.

This is a bit problematic for us, cause we are relying on the files checksum (we are calculating it with crc32c) in order to serve only the delta asset bundles each time.

The version, which is included in the AssetBundle file, will cause us to serve all of our asset bundles to our users whenever we are updating the unity version and have to build asset bundles (without updating the app).

Is there something that we are missing? Is there ability to remove this metadata from the AssetBundles during the assets build?

If not, how do you recommend to identify if an asset bundle need to be re-downloaded, due to a new version?

 

You can't mix asset bundles between Unity versions, can you? That would be why the Unity version is on the first line.

I'm not currently using asset bundles, so maybe my understanding is not correct or is outdated.

 

The asset bundle file format allows for sharing between Unity versions. That doesn't help though if the new Unity version changed the way it handles the specific content you're including in your bundles, which would then require you to create new bundles regardless.

 

If I'll work with unity built-in crc:

https://docs.unity3d.com/ScriptReference/AssetBundleManifest.GetAssetBundleHash.html

Will it survive unity version updates?
I mean if I build Asset A with version 2017.3.1 and it's crc is X, then I'll build it with 2017.4.1, will it's crc remains X?

 

Hmm ... you really need to be asking these questions in the Asset Bundle section of the forum. They could set you straight, I bet.

 

Thanks, I've found a related question over there:
https://forum.unity.com/threads/project-update-gives-all-assets-a-new-crc.523074/