====== Object array visualization tip ======

There is a limit in the dashboard object size due to certain performance issues (not more than 199 elements or more than 400000 bytes)). Sometimes users need a very big and rich dasboard visualization, which may lead to excceding this limit. 

In this cases, some optimization trick maybe used. 
Following are the examples of such extensive dashboard graphics:

=== Example 1 - coke furnaces complex ===
Along the raw of ~60 furnaces, a process state needed to be shown in the furnace place, from both sides, which means ~120 graphical objects. 
{{ network:screen_shot.jpg?direct&600 |}}

=== Example 2 - big drying furnace ===
There is an array of burners inside the furnace, each of the burner requires a set of binary indicators, which require a huge amount of visualization elements. 

{{ network:дашборд_сушило_cleaned.png?direct&600 |}}

==== The solution ====

The solution was to pack all the elements into one string object, with each character reflecting the state of the respective process object. 

The idea is shown on the following gif images:
{{ network:2021-07-22_15-51-00.gif?direct |}}

{{ network:2021-07-22_17-18-41.gif?direct |}}

== The code which makes the trick ==

<code lua>
TRUE_SYMBOL =  '⚠'
FALSE_SYMBOL = '-'
NUMBER_OF_SPACES = 2 

function main (userId)
    
   local bit_mask = R("demo_mask")
   local t = {}
   
   for b = 8, 1, -1 do 
        local symbol = hasbit(bit_mask, b) and TRUE_SYMBOL or FALSE_SYMBOL
        table.insert(t, symbol)
   end 
   
   local out = table.concat(t, string.rep(' ', NUMBER_OF_SPACES)) ; INFO("result_table: " .. out)
   
   U("demo_string", out)
end

-- HELPERS -- 
function bw(n) 
    return 2 ^ (n - 1)   -- returns weight of the bit in pos. n
end
 
function hasbit(x, b) 
  local p = bw(b)
  return x % (p + p) >= p  -- returns if b is true/false; if hasbit(value, b) then ...
end

function U(reg, new_value)
    local cur_value = R(reg)
    if cur_value and new_value and (cur_value ~= new_value) then 
        WriteReg(reg, new_value)
    end 
end 

</code>

Using the font size and spacing adjusment in the lua script you can get necessary dimensions of this object.