Message Handler

A message handler enqueues network messages received from a remote source and applies their contained operations to a world.

Handling Messages#

A message handler is created using the createMessageHandler function:

import { createMessageHandler } from "@javelin/net"
const messageHandler = createMessageHandler()

Message handlers expose a push method for enqueuing new messages along with a system that drains the message queue and applies the operations encoded in each message to the world.

const world = createWorld({ systems: [messageHandler.system] })
// subscribe to remote messages
channel.listen(message => messageHandler.push(message))

Reacting To Changes#

A message handler exposes an effect that can be used to inspect the remote world state, a Set of patched entities, and a Set of updated entities.

const sysNet = () => {
  const {
    remote: { tick },
    updated, // entities updated last message
  } = messageHandler.useInfo()
  // ...

  qryBodies(e => {
    if (updated.has(e)) {
      interpolate(e)
    }
  })
}