How exactly does batching work with dynamic lights?

[brisingre]

I have a very general question about batching. What actually relates the number of batches to the number of lights/meshes/materials in the scene?

As I understand, with no batching, it’s roughly 1/Material/MeshRenderer, and with static batching it’s something like 1/Material? But I don’t think any of that’s quite right, and I don’t know how lights affect it at all.

Usually non-shadowcasting lights seem to add 1 or 2 per light, and shadowcasting lights add 6-8, but sometimes, as in these screenshots, a point or spot light seems to be taking my batches apart, and making a new batch for every mesh in its radius.

This happens on Forward, Deferred, and to a lesser extent even on Vertex Lit. (Vertex Lit only adds about a hundred batches instead of about five hundred.)

Does anyone know what to do about this? Would someone mind explaining the rules for what has to go in a new batch? Are there any best practices to follow when working with dynamic lights and runtime-instantiated tiles?

Thanks!

Edit: Better illustration, with normal Unity cubes – no probuilder. I’m also sure it’s not lux.

[brisingre]

Think I figured this out. I wasn’t actually rendering with deferred. I thought I was, but I had an asset that had quietly replaced the camera inspector with a slightly different one. The one it replaced it with was obsolete, and seeing that I didn’t have Unity Pro, helpfully set my camera to Forward and threw a warning I ignored.

Vertex Lit does still have weird behavior with batching though. Dunno what’s up with that.