GetElementsByType

From Multi Theft Auto: Wiki
Revision as of 10:39, 1 June 2010 by EAi (talk | contribs) (→‎Example)
Jump to navigation Jump to search

This function is used to retrieve a list of all elements of the specified type. This can be useful, as it disregards where in the element tree it is. It can be used with either the built in types (listed below) or with any custom type used in a .map file. For example, if there is an element of type "flag" (e.g. <flag />) in the .map file, the using "flag" as the type argument would find it.

Syntax

Click to collapse [-]
Server
table getElementsByType ( string theType, [ element startat=getRootElement() ] ) 
Click to collapse [-]
Client
table getElementsByType ( string theType, [ element startat=getRootElement(), bool streamedIn=false ] ) 


Required Arguments

  • theType: The type of element you want a list of. This is the same as the tag name in the .map file, so this can be used with a custom element type if desired. Built in types are:
    • "player": A player connected to the server
    • "ped": A ped
    • "water": A water polygon
    • "sound": A playing sound
    • "vehicle": A vehicle
    • "object": An object
    • "pickup": A pickup
    • "marker": A marker
    • "colshape": A collision shape
    • "blip": A blip
    • "radararea": A radar area
    • "team": A team
    • "spawnpoint": A spawnpoint
    • "remoteclient": A remote client connected to the server
    • "console": The server Console


Optional Arguments

NOTE: When using optional arguments, you might need to supply all arguments before the one you wish to use. For more information on optional arguments, see optional arguments.

  • startat: The element the search should start at. Children of this element are searched, siblings or parents will not be found. By default, this is the root element which should suit most uses.
Click to collapse [-]
Client
  • streamedIn: If true, function will only return elements that are streamed in.

(PS: lil_Toady is a commie)

Returns

Returns a table containing all the elements of the specified type. Returns an empty table if there are no elements of the specified type. Returns false if the string specified is invalid (or not a string).

Example

This example retrieves a table of the players in the server, and checks whether or not each one is in a vehicle:

local players = getElementsByType ( "player" ) -- get a table of all the players in the server
for theKey,thePlayer in ipairs(players) do -- use a generic for loop to step through each player
   if ( isPlayerInVehicle ( thePlayer ) ) then -- if the player is in a vehicle, announce it
      outputChatBox ( getPlayerName ( thePlayer ) .. " is in a vehicle" )
   else -- if the player isn't in a vehicle, announce that he/she is on foot
      outputChatBox ( getPlayerName ( thePlayer ) .. " is on foot" )
   end
end

This shows how you could create a new element to describe a gas station:

function createGasStations(below)
    local gasstations = getElementsByType ( "gasstation", below ) -- get a table of all the players in the server
    for theKey,theGasStation in ipairs(gasstations) do -- use a generic for loop to step through each player
        x = getElementData(theGasStation, "posX")
        y = getElementData(theGasStation, "posY")
        z = getElementData(theGasStation, "posZ")
        setElementParent(createColSphere(x, y, z, 10), theGasStation)
        addEventHandler("onColShapeHit", theGasStation, giveGas)
    end
end

function mapLoad()
    createGasStations(source) -- create gas stations for the map that's just loaded
end
addEventHandler("onResourceStart", getRootElement(), mapLoad)

function giveGas(hittingElement)
    local theGasStation = source
    if getElementType(hittingElement) == "vehicle":
        gas_left = getElementData(theGasStation, "amount")
        gas_speed = getElementData(theGasStation, "speed")
        if gas_left > 0 then
            if gas_left < gas_speed then
                gas_to_remove = gas_left
            else
                gas_to_remove = gas_speed 
            end
            current_vehicle_gas = getElementData(hittingElement, "gas")
            current_vehicle_gas = current_vehicle_gas + gas_to_remove
            gas_left = gas_left - gas_to_remove
            setElementData(hittingElement, "gas", current_vehicle_gas)
            setElementData(theGasStation, "amount", gas_left)
        else
            outputChatBox("Pump is out of gas!")
        end
    end
end

See Also