OnRep vs multicast

[PRESSURE2000]

@Sam Bonifacio

Alright, let’s say you have a replicated Actor but it’s not network relevant to a client.

If the server wants the Actor to explode, it could trigger a multicasted event which plays an explosion effect. Clients where the Actor isn’t network relevant don’t need to see the explosion and they won’t.

Though let’s say the server wants to change the colour of the Actor and have the change replicated to clients. If the server triggers a multicast event to change the colour, that will fire on all the clients where the actor is network relevant.

That means (generally) that clients close to the Actor will see the updated colour, but clients far away won’t get the event to update the colour so they’ll still see the old one indefinitely.

If you have a replicated variable to control the colour state with an OnRep instead, even if the Actor isn’t relevant the OnRep will fire when the Actor becomes network relevant again and the colour will update correctly.

So basically: Use OnRep when you need to replicate a change in persistant state and multicast events for temporary things that won’t matter in the future.

Also, my golden rule with reliable is to use it when an event or variable change must get to the client, and not reliable when it’s something that updates a lot (like every frame) and it doesn’t matter if an update gets lost.

so should we be doing both?

multicast and onrep so when the actor becomes relevant it works vs it being just multicast?

I heard people saying dont use multicast because it will cause lag