Drawing Lifetime

Drawing calls build output that LuaHUD keeps and paints on the HUD. How long that output stays depends on the callback that created it and the section options.

Ordinary output belongs to its callback

Without duration, a section lasts until the same callback runs again. Before that call stars, LuaHUD removes that callback’s previous ordinary output.

lh.on("tick", function()
    if lh.player.sprinting then
        lh.drawln("Sprinting")
    end
end)

When you stop sprinting, the next call removes the old line even though it draws nothing. This is why conditional HUD elements don’t need a separate erase function.

Each registered callback has its own output. A tick callback doesn’t clear a differenct callback’s section, even if both are in the same profile. Each also starts from the default layout, so assing positions if they might overlap.

Top-level drawins follow the same idea, but that code only runs on load. Their values won’t refresh just because the game does. Drawing made in reload also remain until a runtime reload clears them.

Temporary output uses duration

Pass a positive duration in seconds to keep a section until lifetime expires:

lh.on("reload", function()
    lh.section({
        anchor = "topCenter",
        offsetY = 20,
        duration = 5,
    })
    lh.drawln("Welcome back, " .. lh.player.name .. "!")
end)

A temporary section survives later calls to the callback that created. That is what makes event-driven notifications work, but it also means drawing an anonymous temporary section on every tick creates many overlapping sections. Create it only when something happens, or give it an ID.

The default duration clock is real time. The sectionDurationClock setting in config/luahud.json can use "gameTime instead of "realTme. Game time advances by client ticks while the game isn’t paused.

IDs replace sections

id gives a section a shared name. Starting a section with that ID removes the previous section with the same ID, including one created by another callback or profile.

local function notify(message)
    lh.section({
        id = "reload-notice",
        duration = 3,
        anchor = "topCenter",
        offsetY = 20,
    })
    lh.drawln(message)
end

lh.on("reload", function()
    notify("HUD loaded")
end)

Call notify() again and it replaces the text and restarts the three-second lifetime. An ID doesn’t create a position or prevent overlap with sections that have other IDs.

All output is cleared on runtime reload when leaving the world. A duration section doesn’t survive those transitions.