.spriteatlas hash is recalculate to another value very often.

Questions & Answers
1

I am using new sprite atlas feature that is built in since Unity2017.

It will works almost fine. But there contains hash numbers are recalculate very often.
It represented when even i didn’t modified anything.
I just played the editor.

%YAML 1.1
%TAG !u! tag:unity3d.com,2011:
--- !u!687078895 &4343727234628468602
SpriteAtlas:
  m_ObjectHideFlags: 0
  .... lines ....
    packedHash:
      serializedVersion: 2
      Hash: f2629172dcecfa8f7bdf787bd034f4df
  .... lines ....
    hashString: f2629172dcecfa8f7bdf787bd034f4df
  .... lines ....

This is part of .spriteatlas asset file contents.
You could see two lines of hash number that issues.

I have a question.
When does Unity modifies that hash numbers?
And what are these hashes generated based on?

Best Regards.

2

I have the same issue.

I think hash is based on a target platform. This could mean that if 1 dev is working on Android and other on iOS, then both programmers will override each others hashes on a repository. But thats just my theory.

3

Unity regenerates the hash every time the sprite atlases are repacked. Presumably the packing process is non-deterministic, meaning every time it repacks, you’ll get a slightly different atlas and with a different hash.

Check your project editor settings (Edit > Project Settings > Editor), and under Sprite Packer > Mode you most likely have the setting Always Enabled . This is fine if you want to test your sprite atlas packing in the editor so you can debug sprite batching issues or similar, but it’s not necessary to permanently work this way. Change it to Enabled For Builds and it will only repack the sprite atlases when you perform a build. This will minimize changes for your version control.