alt:V player look sync

client.js

import alt from "alt-client"
import native from "natives"

const localPlayer = alt.Player.local
const SYNC_MS_DELAY = 500
const SYNC_MS_DELAY_REMOTE = 100
const MAX_HEADING_DIST = 70.0
const BACKWARDS_HEADING_DIST = 145.0
const TASK_LOOK_AT_COORD_DURATION = 300
const LOOKING_AT_POS_OFFSET = 5.0

let lastSendedLookingAtPosString
const sendServer = (lookingAtPos) => {
  let posString = ""

  if (lookingAtPos) {
    posString = lookingAtPos
      .toArray()
      .map(v => v.toFixed(1))
      .join("|")
  }

  if (lastSendedLookingAtPosString === posString) return

  alt.emitServer(
    "sync-player-look-at",
    posString,
  )
}

let prevPlayerHeading = -1
let prevCamRot = alt.Vector3.zero

alt.setInterval(() => {
  let camRot = native.getGameplayCamRot(2)
  const playerHeading = localPlayer.rot.toDegrees().z

  if (
    (
      prevCamRot.x.toFixed(1) === camRot.x.toFixed(1) &&
      prevCamRot.y.toFixed(1) === camRot.y.toFixed(1) &&
      prevCamRot.z.toFixed(1) === camRot.z.toFixed(1)
    ) &&
    (playerHeading.toFixed(1) === prevPlayerHeading.toFixed(1))
  ) return

  prevCamRot = camRot
  prevPlayerHeading = playerHeading

  const camHeading = camRot.z

  // if player is looking backwards block player head heading at MAX_HEADING_DIST
  const headingDist = distanceDegrees(camHeading, playerHeading)

  if (headingDist > BACKWARDS_HEADING_DIST) {
    sendServer(null)
    return
  }

  if (headingDist > MAX_HEADING_DIST) {
    // why i wrote something like this? don't ask me
    const a = playerHeading + MAX_HEADING_DIST
    const b = playerHeading - MAX_HEADING_DIST
    const aDist = distanceDegrees(camHeading, a)
    const bDist = distanceDegrees(camHeading, b)
    const closest = aDist < bDist ? a : b
    camRot = new alt.Vector3(camRot.x, camRot.y, closest)
  }

  const direction = rotationToDirectionDegrees(camRot)
  const lookingAtPos = direction.mul(LOOKING_AT_POS_OFFSET).add(localPlayer.pos)

  sendServer(lookingAtPos)
}, SYNC_MS_DELAY)

alt.setInterval(() => {
  for (const player of alt.Player.streamedIn) {
    const posString = player.getStreamSyncedMeta("sync-player-look-at")
    if (!posString) continue

    const pos = posString
      .split("|")
      .map(v => +v)

    native.taskLookAtCoord(player, ...pos, TASK_LOOK_AT_COORD_DURATION, 0, 0)
  }
}, SYNC_MS_DELAY_REMOTE)

function rotationToDirectionDegrees(rotation) {
  const z = rotation.z * (Math.PI / 180.0)
  const x = rotation.x * (Math.PI / 180.0)
  const num = Math.abs(Math.cos(x))

  return new alt.Vector3(
    (-Math.sin(z) * num),
    (Math.cos(z) * num),
    Math.sin(x),
  )
}

function distanceDegrees(a, b) {
  let dist = Math.abs(a % 360 - b % 360)
  dist = Math.min(dist, 360 - dist)

  return dist
}

server.js

import alt from "alt-server"

alt.onClient("sync-player-look-at", (player, posString) => {
  player.setStreamSyncedMeta("sync-player-look-at", posString)
})