Working with events

Callbacks let a script respond when the runtime or game has something to report.

Register a callback

local function on_hurt(event)
    local victim = client.userid_to_entindex(event.userid)
    if victim == entity.get_local_player() then
        client.log("Damage taken: ", event.dmg_health)
    end
end

client.set_event_callback("player_hurt", on_hurt)

Game event user IDs are not entity indexes. Convert them before passing them to entity functions.

Remove a callback

client.unset_event_callback("player_hurt", on_hurt)

Keep the function reference if you plan to unregister it later. Passing a newly created function does not identify the original callback.

Drawing callbacks

Use paint for in-game visuals. Keep expensive initialization and repeated file parsing outside per-frame callbacks. Cache reusable data, then draw from it.

Event reference

The sidebar separates runtime events, Source engine events and CS:GO events. These imported event descriptions are an upstream reference, not a guarantee that every event is emitted by the 2018 game or this runtime.