ESOUI - Get Map Coordinates of cursor

Found it here.

Code:

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--        Coordinate System          --

-----------------------------------------



function EH.UpdateCoordinates()

    local mouseOverControl = WINDOW_MANAGER:GetMouseOverControl()



    if (mouseOverControl == ZO_WorldMapContainer or mouseOverControl:GetParent() == ZO_WorldMapContainer) then

        local currentOffsetX = ZO_WorldMapContainer:GetLeft()

        local currentOffsetY = ZO_WorldMapContainer:GetTop()

        local parentOffsetX = ZO_WorldMap:GetLeft()

        local parentOffsetY = ZO_WorldMap:GetTop()

        local mouseX, mouseY = GetUIMousePosition()

        local mapWidth, mapHeight = ZO_WorldMapContainer:GetDimensions()

        local parentWidth, parentHeight = ZO_WorldMap:GetDimensions()



        local normalizedX = math.floor((((mouseX - currentOffsetX) / mapWidth) * 100) + 0.5)

        local normalizedY = math.floor((((mouseY - currentOffsetY) / mapHeight) * 100) + 0.5)



        EsoheadCoordinates:SetAlpha(0.8)

        EsoheadCoordinates:SetDrawLayer(ZO_WorldMap:GetDrawLayer() + 1)

        EsoheadCoordinates:SetAnchor(TOPLEFT, nil, TOPLEFT, parentOffsetX + 0, parentOffsetY + parentHeight)

        EsoheadCoordinatesValue:SetText("Coordinates: " .. normalizedX .. ", " .. normalizedY)

    else

        EsoheadCoordinates:SetAlpha(0)

    end

end

Where can I find documentation for these functions?
http://wiki.esoui.com/Raw_globals_dump
I see many addons using them but can't seem to find out how to use them.