Authority, role, and owning connection

Keep the concepts separate

Concept	Answers
Authority / local role	Which machine owns this actor's canonical replicated copy?
Owner	Which Actor is this actor's UE owner?
Owning connection	Which client connection is reached through the owner chain to a PlayerController?
Local control	Is this Pawn/Controller controlled by a local player on this machine?
Relevancy	Should this connection currently receive this actor?

Network role is not ownership. A server has authority over replicated gameplay actors, while a client may own a connection to its PlayerController/Pawn and therefore be permitted to call Server RPCs through that chain.

Client request path

local input/UI
  -> locally owned PlayerController, Pawn, or owned replicated component
  -> Server RPC carrying minimal intent
  -> server validates current canonical state, range, permissions, rate, and target
  -> server mutates canonical state
  -> properties/RPCs replicate the result

Do not put Server RPCs on arbitrary world actors and expect clients to call them. Route the request through an owned actor, then have server code interact with the target.

Validation checklist

Validate on the server:

• requesting connection may perform the action;
• actor and target still exist and are relevant to the rule;
• distance, line of sight, cooldown, resources, and state preconditions;
• numeric values are bounded and derived server-side where possible;
• request rate/sequence is acceptable;
• the request cannot select objects hidden from that player;
• repeated or reordered requests are safe/idempotent where needed.

WithValidation is an available C++ RPC mechanism, but server gameplay logic must still enforce rules regardless of where validation is written.

Spawn and destruction

• Spawn replicated gameplay actors on the server.
• Destroy them on the server.
• A client-spawned actor is local to that client unless it participates through another authoritative mechanism; setting Replicates on the client copy does not create the server copy.
• Cosmetic local actors are allowed when they have no gameplay authority.

UI boundary

Widgets are not replicated actors and should not own RPCs. A widget emits intent to its owning local controller/pawn/component. It observes replicated state through a presenter/Viewmodel.