Question Why is "Static Shadow Caster" separate from other static flags? Should I enable it?

It looks like the setting "Static Shadow Caster" on a renderer should be enabled when using lighting not set to update every frame, but rather with "Always Update Dynamic" enabled:

https://docs.unity3d.com/Packages/c...h-definition@11.0/manual/Shadows-in-HDRP.html

I'm confused about why "Static Shadow Caster" isn't among the other static flags (Contributes GI, Batching static, etc). It seems that in almost all cases, if I make an object fully static, I'd want "Static Shadow Caster" enabled as well. But it looks like I'll need to tick that box separately for every renderer, one at a time, versus the static flags' ability to recursively set the property of many child objects at once.

Is there any drawback to enabling "Static Shadow Caster", assuming the object really doesn't ever move? What's the reasoning for it not being with the other static flags? Is that just a limitation of the engine, that an SRP can't inject other static flags?

 

Thanks. I experimented with Mixed Cached Shadows maybe a month ago, to judge whether I could achieve performance gains by setting most of my lights to update "On Enable" instead of "Every Frame", and enabling "Always Draw Dynamic" on the lights. I didn't really notice any performance change one way or the other at the time. But perhaps I needed to set the various static geometry to "Static Shadow Caster" to have benefited from that? I guess I'll test that out again.

 

Good point. Someone in another thread (https://forum.unity.com/threads/whi...ould-i-use-on-my-lights.1381941/#post-8706540) did mention to me that sample costs aren't affected by this, and that they're the lions share of the shadowing. So, I probably shouldn't expect big gains by enabling this. But it's good to know I'll at least be enabling the feature in the correct way.