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-- DON'T TOUCH ANYTHING BELOW UNLESS YOU KNOW WHAT YOU'RE DOING
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local compass_offset_inches = compass_offset_feet * 12
local compass_radius_inches = compass_radius_feet * 12
local WINDOW_NAME_TEMPLATE  = "T_Compass3D_Point"

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-- Core
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Compass3D = Compass3D or {}

function Compass3D.OnInitialize()
    Compass3D.Camera.OnInitialize()

    for i = 1, #compass_windows do
        local w = compass_windows[i]

        -- Create UI element
        CreateWindowFromTemplate(w.name, WINDOW_NAME_TEMPLATE, "Root")
        WindowSetShowing(w.name, true)
        WindowSetScale(w.name, w.scale * InterfaceCore.GetScale())
        WindowSetTintColor(w.name, w.red, w.green, w.blue)

        -- Set icon
        local texture, tx, ty = GetIconData(w.icon)
        DynamicImageSetTexture(w.name .. "_Icon", texture, tx, ty)

        w.offset_x = w.direction_x * compass_radius_inches
        w.offset_y = w.direction_y * compass_radius_inches
    end
end

function Compass3D.OnShutdown()
    Compass3D.Camera.OnShutdown()
    for i = 1, #compass_windows do
        DestroyWindow(compass_windows[i].name)
    end
end

function Compass3D.OnUpdate(time_delta_s)
    local camera_pivot_x, camera_pivot_y, camera_pivot_z, camera_pivot_zone_id = Compass3D.Camera.GetPivotZonePosition()

    -- Hide all points if camera is unavailable
    if not camera_pivot_x then
        for i = 1, #compass_windows do
            WindowSetAlpha(compass_windows[i].name, 0)
        end
        return
    end

    -- Convert screen dimensions to UI-logical pixels
    local screen_width, screen_height = GetScreenResolution()
    screen_width = screen_width / InterfaceCore.GetScale()
    screen_height = screen_height / InterfaceCore.GetScale()
    local center_x, center_y = screen_width * 0.5, screen_height * 0.5

    -- Update every compass point
    for i = 1, #compass_windows do
        local window = compass_windows[i]

        -- Calculate world-space position
        local world_x = camera_pivot_x + window.offset_x
        local world_y = camera_pivot_y + window.offset_y
        local world_z = camera_pivot_z + compass_offset_inches

        -- Project to screen
        local visible, screen_x, screen_y = WorldToScreen(world_x, world_y, world_z)
        screen_x = screen_x / InterfaceCore.GetScale()
        screen_y = screen_y / InterfaceCore.GetScale()

        -- Set alpha (0 if not visible or off-screen)
        local new_alpha = (visible and
                          screen_x >= 0 and screen_x <= screen_width and
                          screen_y >= 0 and screen_y <= screen_height)
                          and window.alpha or 0

        WindowSetAlpha(window.name, new_alpha)

        -- Update position if visible
        if new_alpha > 0 then
            WindowClearAnchors(window.name)
            WindowAddAnchor(window.name, "center", "Root", "center",
                          screen_x - center_x, screen_y - center_y)
        end
    end
end