Script callbacks

A script can define up to five callbacks. All callbacks are optional. Use the preferred names in new scripts.

Callback order

Callback	Arguments	Use it for
Load	assignedPlayerId	Create script-wide values and write one startup log.
Init	None	Reset values that belong to one match.
Update	deltaSeconds	Read game data, make decisions, and submit bounded commands.
Render	None	Draw text, shapes, and world markers.
Shutdown	None	Release Lua state and write one final log.

Load runs when WololoLabs loads the script. A match might not be ready yet.

Init runs before the first update in each ready match. It can run again after a match ends and another match starts. Reset object IDs, timers, and flags here.

Update can run while the game is unavailable. Check for nil, 0, and empty arrays before you use a result.

Separate update work from drawing

Use Update to read data and decide what to do. Use Render to draw output. Store only Lua values, such as strings, numbers, colors, and positions, between the callbacks.

local label = "Waiting for a match"

function Update()
    local player = GetAssignedPlayer()
    label = player and player:GetPlayerName() or "Waiting for a match"
end

function Render()
    RenderTopRightText(label, 12, 12, 14, Color("#FFFFFFFF"), true)
end

A drawing view can be unavailable during loading or a state change. A drawing function can then produce no visible result. Do not use a screen query as game logic.

Require helper modules

Each script has its own require cache. A helper module runs once for each loaded script instance.

Use require only for files below the module entry folder. Return a table from each helper module. Keep callbacks in the entry file.

local format = require("format")

function Render()
    RenderTopRightText(format.label(), 12, 12)
end

Do not use load, loadfile, dofile, or package.path to load a script.

Handle errors

An error in Init, Update, or Render stops only that callback. WololoLabs records the script path and callback name, continues with other scripts, and tries that callback again later. Check the Log Terminal for load or shutdown errors because they can have different reporting.

Handle expected missing game data with normal checks. Do not use pcall to hide a permanent script error. Log the state that explains a real failure.

Reload and shutdown

WololoLabs calls Shutdown before it unloads or replaces a script. Keep this callback short. Do not rely on the game state during shutdown.

Use the Reload button after you edit a script. Reload creates a new script state. Top-level values and require caches do not survive the reload.

Older callback names

Older name	Current callback	Note
onLoad	Load	Receives the assigned player ID.
onInit	Load	Used only when neither Load nor onLoad exists. Receives the assigned player ID.
onTick	Update	Receives elapsed seconds.
onDraw	Render	No arguments.
onShutdown	Shutdown	No arguments.

Init has no older-name fallback. New scripts must use Load, Init, Update, Render, and Shutdown.