So in my update to 1.10.2 I finally have my items rendering, but I have run into a question that I want to understand better. The first version of my mod was for 1.8.9. I had a class for registering my item renderers which was called from my ClientProxy's pre-init method. I had understood that item renderers are only used on the client side. My items themselves were registered from CommonProxy.

 

Now, after following some recommendations for updating to 1.10.2, I have a single method that's called from CommonProxy, and it both registers the items and the item renderers. It's definitely simpler this way. What is the difference between registering the item renderers from CommonProxy versus ClientProxy? Would it be somehow better to separate out the item renderers and call them from ClientProxy, like I used to do?

You should be rendering your renderers in the client proxy.  The "difference" is that the client proxy only loads on the CLIENT not the SERVER because the server doesn't know jack about models and textures.

The currently recommended way to register things like

Item

s and models is using the recently-added registry events.

 

I explain them here.