Voilà, j’ai utilisé les mêmes noms que vos variables avec un X initial pour indiquer les bougies Heikin-Ashi :

defparam drawonlastbaronly = true

alpha = 500 //from 0 to 255 to change alpha transparency

dop = dopen(0)
dhi = dhigh(0)
dlo = dlow(0)
dcl = dclose(0)

// Heikin - Ashi candlesticks
once xDop = dop
xDcl     = (dop + dcl + dhi + dlo) / 4
if barindex > 0 then
xDop  = (xDop + xDcl[1]) / 2
endif
xDlo       = min(dcl,min(xDcl,xDop))
xDhi       = max(dhi,max(xDcl,xDop))

//candlestick color
if xdop>xdcl then
direction = -1
else
direction = 1
endif

//bullish candle
if direction = 1 then
//candlestick body
DRAWRECTANGLE(barindex-5,xdop,barindex,xdcl) COLOURED(50,205,50,alpha)style(line,3)
//candlestick high and low
DRAWRECTANGLE(barindex-3,xdcl,barindex-2,xdhi) COLOURED(50,205,50,alpha)style(line,3)
DRAWRECTANGLE(barindex-3,xdop,barindex-2,xdlo) COLOURED(50,205,50,alpha)style(line,3)
endif

//bearish candle
if direction = -1 then
//candlestick body
DRAWRECTANGLE(barindex-5,xdcl,barindex,xdop) COLOURED(220,20,60,alpha)style(line,3)
//candlestick high and low
DRAWRECTANGLE(barindex-3,xdop,barindex-2,xdhi) COLOURED(220,20,60,alpha)style(line,3)
DRAWRECTANGLE(barindex-3,xdcl,barindex-2,xdlo) COLOURED(220,20,60,alpha)style(line,3)
endif

RETURN