Add a zoom function to an existing currency strength indicator

Hi

i am looking for someone who know how to make a zoom function of lines currencies

the zoom function consist to display N last candle beginning at 0 line, on the full number of candle of the chart windows ,

by example with parameter zoom ON :

- display the last 10 candle on a windows which display by example 20 candles means it is a "zoom X2"

- display the last 5 candle on a windows which display by example 20 candles means it is a "zoom X4"

- the number of "zoom display" is automatically determined by the indicator depending of the wide candle of the window

here after screenshot of last 10 candles display on a chart which has the wide of 20 candles (zoom X 2) 

by example with parameter zoom OFF :

- display the last 10 candle on a windows which is wide of 20 candles means no zoom and all the lines begin at -10 candles

- display the last 5 candle on a windows which display by example 20 candles means it is a "zoom X4"

- in this case no zoom function and all the lines begin at minus "last candle" until actual candle

here after screenshot of last 10 candles display on a chart which has the wide of 20 candles and NO ZOOM 

eventually some light updates could be made also

the 2 screenshot was taken with +- 2 minutes

and we could make this more clear

Thank you

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