i also post it here https://forum.unity.com/threads/why-editorutility-setdirty-triggers-full-bake-of-subscene.1516642/
the actual need is, how to trigger a correct incremental baking when dealling with custom editor ?
#Why EditorUtility.SetDirty triggers full bake of subscene
floral geyser
frozen ether
Hey filod. I replied on the forum post. You need to guard the EditorUtility.SetDirty.
regal dove
If you modify a property with setdirty, this will re-trigger rebake no matter what. This will be reported by unity has object changed and the bake will react.
As niki said, you need to guard and set dirty only if things has chaged.