function PlateText(commandName,text,also)
local Vehicle = getPedOccupiedVehicle(getLocalPlayer())
if Vehicle then
if text and not also then
   setVehiclePlateText( Vehicle, text )
elseif text and also then
   setVehiclePlateText( Vehicle, text .. \" \" .. also )
else
    outputChatBox(\"Kénes szöveg is nemigaz?\",localPlayer)
end
else
outputChatBox(\"Úgy látom nem vagy kocsiban\",localPlayer)
end
end
end
addCommandHandler(\"setrendszam\",PlateText)

function dxDrawTextOnElement(TheElement,text,height,distance,R,G,B,alpha,size,font,checkBuildings,checkVehicles,checkPeds,checkDummies,seeThroughStuff,ignoreSomeObjectsForCamera,ignoredElement)
      local x, y, z = getElementPosition(TheElement)
      local x2, y2, z2 = getElementPosition(localPlayer)
      local distance = distance or 20
      local height = height or 1
                                local checkBuildings = checkBuildings or true
                                local checkVehicles = checkVehicles or false
                                local checkPeds = checkPeds or false
                                local checkObjects = checkObjects or true
                                local checkDummies = checkDummies or true
                                local seeThroughStuff = seeThroughStuff or false
                                local ignoreSomeObjectsForCamera = ignoreSomeObjectsForCamera or false
                                local ignoredElement = ignoredElement or nil
      if (isLineOfSightClear(x, y, z, x2, y2, z2, checkBuildings, checkVehicles, checkPeds , checkObjects,checkDummies,seeThroughStuff,ignoreSomeObjectsForCamera,ignoredElement)) then
         local sx, sy = getScreenFromWorldPosition(x, y, z+height)
         if(sx) and (sy) then
            local distanceBetweenPoints = getDistanceBetweenPoints3D(x, y, z, x2, y2, z2)
            if(distanceBetweenPoints < distance) then
               dxDrawText(text, sx+2, sy+3.5, sx, sy, tocolor(R or 255, G or 255, B or 255, 100), (size or 1)-(distanceBetweenPoints / distance), font or \"arial\", \"center\", \"center\")
   end
end
end
end
 
function keszrendszam()
for k,v in ipairs(getElementsByType(\"vehicle\")) do
        local rendszam = getVehiclePlateText(v) 
local visible = getElementData(getLocalPlayer(), \"rendszam\") or 0
if visible == 1 then
if rendszam then 
dxDrawTextOnElement(v,rendszam,0.8,16,255,255,255,255,2,\"arial\")
end
end
end
end
addEventHandler(\"onClientRender\", getRootElement(), keszrendszam)
--[[addCommandHandler(\"teszt\", function()
setElementData(getLocalPlayer(), \"rendszam\", 1)
end)
addCommandHandler(\"teszt2\", function()
setElementData(getLocalPlayer(), \"rendszam\", 0)
end)]]--
function nulla()
setElementData(getLocalPlayer(), \"rendszam\", 0)
end
addEventHandler(\"onClientPlayerJoin\", getRootElement(), nulla)
addEventHandler(\"onClientPlayerQuit\", getRootElement(), nulla)
addEventHandler(\"onClientResourceStart\", getRootElement(), nulla)
addEventHandler(\"onClientResourceStop\", getRootElement(), nulla)
function ream()
local rendszam = getElementData(getLocalPlayer(), \"rendszam\") or 0
if rendszam == 0 then
setElementData(getLocalPlayer(), \"rendszam\", 1)
--outputChatBox(\"asd\")
elseif rendszam == 1 then
setElementData(getLocalPlayer(), \"rendszam\", 0)
--outputChatBox(\"kecske\")
end
end
bindKey(\"F10\", \"down\", ream)
function PlateText(commandName,text,also)
local Vehicle = getPedOccupiedVehicle(getLocalPlayer())
if Vehicle then
if text and not also then
   setVehiclePlateText( Vehicle, text )
elseif text and also then
   setVehiclePlateText( Vehicle, text .. \" \" .. also )
else
    outputChatBox(\"Kénes szöveg is nemigaz?\",localPlayer)
end
else
outputChatBox(\"Úgy látom nem vagy kocsiban\",localPlayer)
end
end
end
addCommandHandler(\"setrendszam\",PlateText)

A rendszám változtatást szerver oldalon illik megcsinálni, mert ha nem, akkor csak a lokális játékosnak változtatja meg.
 

function PlateText(thePlayer, commandName, text, also)
        local vehicle = getPedOccupiedVehicle(thePlayer)
        local adminlevel = getElementData(thePlayer, \'adminlevel\')
        if (adminlevel >= 9) then
        if vehicle then
                if text and not also then
                        setVehiclePlateText( vehicle, text )
                elseif text and also then
                        setVehiclePlateText( vehicle, text .. \" \" .. also )
                else
                    outputChatBox(\"Kéne szöveg is nemigaz?\", thePlayer)
                end
        else
                outputChatBox(\"Úgy látom nem vagy kocsiban\", thePlayer)
        end
        end
end
addCommandHandler(\"setrendszam\",PlateText)

 
Így már működnie kéne.