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Creating a Marker

Phase 1. Upgrading the TriggerFunction​

Continuing on with our TriggerFunction example, now we'll create a new marker above our triggered marker instead of moving the original marker.

To create a marker, we need to make use of the Pack:CreateMarker function. Feel free to check it out.

While you can technically create a marker without passing it any attributes, it's generally a good idea to at least provide some basic attributes.

Let's change our TriggerFunction to create a new marker above the position of the original marker.

tip

It's a good idea to always set the category, so that the new marker can be hidden or shown by toggling your pack's categories.

/Data/ExamplePack/Scripts/TriggerFunction.lua
-- We can use the World global to get a reference to the category we want to use for our new marker
local category = World:CategoryByType("ep.marker.category")

function EP_TriggerFunction(marker, isAutoTrigger, customInput)
    -- For the most part, the attribute names are the same as you'd find in the xml
    local new_marker_attr = {   
        MapVisibility = false,
        InGameVisibility = true,
        Category = category, -- 
        xpos = marker.Position.X,
        ypos = 0,
        zpos = marker.Position.Z,
        iconFile = "Data/ExamplePack/Markers/MarkerIcon.png",
    }

    if isAutoTrigger then
        -- We can adjust the ypos after creating the initial table by just setting it again using the `.` accessor
        new_marker_attr.ypos = marker.Position.Y + 20
    else
        new_marker_attr.ypos = marker.Position.Y + 50
    end

    -- Create the marker
    local new_marker = Pack:CreateMarker(new_marker_attr)
end

Nice! We're making some real progress now. Now when you trigger the marker, a new marker should be created above the original marker.


Phase 2. Another Upgrade​

Let's take this one step further and make it so that interacting with the original marker a second time will remove the new marker.

/Data/ExamplePack/Scripts/TriggerFunction.lua
-- Let's create a table to keep track of our new markers. We'll move the category there too
ExamplePack.TriggerFunction = {
    activeMarkers = {},
    category = World:CategoryByType("ep.marker.category")
}

-- Let's watch that table so we can keep an eye on it in the console too!
Debug:Watch("TriggerFunction", ExamplePack.TriggerFunction)

-- We'll move the logic for spawning and removing markers to new functions
local function spawnNewMarker(marker, isAutoTrigger)
    local new_marker_attr = {   
        MapVisibility = false,
        InGameVisibility = true,
        Category = ExamplePack.TriggerFunction.category,
        xpos = marker.Position.X,
        ypos = 0,
        zpos = marker.Position.Z,
        iconFile = "Data/ExamplePack/Markers/MarkerIcon.png",
    }

    if isAutoTrigger then
        new_marker_attr.ypos = marker.Position.Y + 20
    else
        new_marker_attr.ypos = marker.Position.Y + 50
    end

    local new_marker = Pack:CreateMarker(new_marker_attr)
    -- Let's use the trigger marker's GUID to keep track of it's spawned marker
    ExamplePack.TriggerFunction.activeMarkers[marker.GUID] = new_marker
end

-- Given a GUID, we can remove the marker from the world and then remove it's reference from our table
local function removeNewMarker(guid)
    local spawnedMarker = ExamplePack.TriggerFunction.activeMarkers[marker.GUID]
    if spawnedMarker then
        spawnedMarker:Remove()
        ExamplePack.TriggerFunction.activeMarkers[marker.GUID] = nil
    end
end

-- We aren't using customInput anymore, so let's take that out
function EP_TriggerFunction(marker, isAutoTrigger)
    -- Now we can just perform the check here and offload the logic to the new functions
    if ExamplePack.TriggerFunction.activeMarkers[marker.GUID] ~= nil then
        removeNewMarker(marker.GUID)
    else
        spawnNewMarker(marker, isAutoTrigger)
    end
end

If you've followed along correctly, you should now be able to spawn and remove the new marker by interacting with the trigger marker!