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🙂

Try this (not tested):

Upper = HIGHEST[a](HIGH[1])
Lower = LOWEST[a](LOW[1])
Middle = (Upper + Lower) / 2
If barindex > 2 Then
   Drawsegment(barindex-2,Upper,barindex-1,Upper)   coloured(0,0,255,255)
   Drawsegment(barindex-2,Lower,barindex-1,Lower)   coloured(0,0,255,255)
   Drawsegment(barindex-2,Middle,barindex-1,Middle) coloured(0,255,0,255)
Endif
Return

But you won’t be able to change the style of plotted lines in versions prior to 11.

Unfortunately segments are straight llines, so it’s not possible.

You cannot, since there’s an instruction to allow drawing object only on the last bar, but then you wouldn’t see the previous bars, only the last one drawn. It is useless in your case.

If we display a price label everytime your chart would become so messy!

Try this modified version:

Upper = HIGHEST[a](HIGH[1])
Lower = LOWEST[a](LOW[1])
Middle = (Upper + Lower) / 2
If barindex > 2 Then
   Drawsegment(barindex-2,Upper[1],barindex-1,Upper)   coloured(0,0,255,255)
   Drawsegment(barindex-2,Lower[1],barindex-1,Lower)   coloured(0,0,255,255)
   Drawsegment(barindex-2,Middle[1],barindex-1,Middle) coloured(0,255,0,255)
Endif
Return