How start a retroactive count in Pinescript once a condition is met

Question

I'm plotting an SMA crossover in Pinescript for Tradingview.

Once the crossover occurs, I'd like a retroactive countdown to be displayed as per the image, starting 9 bars back, with the 9th bar at the crossover point.

Conditional retroactive count

Any tips on how I start a conditional retroactive countdown such as this?

Thank you!

I can code the SMA crossover and plot the characters just fine. I just can't figure out how to start a conditional, retroactive count such as this.

Answer 1

Just use a for loop when there is a cross and call label.new() within the loop.

//@version=5
indicator("My script", overlay=true)

sma_9 = ta.sma(close, 9)
sma_50 = ta.sma(close, 50)

plot(sma_9, color=color.green)
plot(sma_50, color=color.red)

sma_cross = ta.crossunder(sma_9, sma_50)

plotshape(sma_cross)

if (sma_cross)
    for i = 0 to 8
        label.new(bar_index[i], high, str.tostring(9 - i), yloc=yloc.abovebar, color=color.new(color.white, 100), textcolor=color.green)