function _pal_swap_layer_start()
{
    if (event_type == ev_draw)
    {
        var _id = ds_priority_delete_min(global.Pal_Layer_Priority);
        var _data = ds_map_find_value(global.Pal_Layer_Map, _id);
        if (ds_list_find_index(_data, undefined) != -1)
            exit;
        pal_swap_set(ds_list_find_value(_data, 0), ds_list_find_value(_data, 1), ds_list_find_value(_data, 2));
        ds_priority_add(global.Pal_Layer_Temp_Priority, _id, layer_get_depth(_id));
    }
}