How do I plot a horizontal line on the high and low of a specific time in Pinescript?

Question

My question is really two parts.

1. How do I plot a horizontal line (that extends to the right but not the left) starting at a specific time of the day, outside of trading hours. I want to plot two horizontal lines actually, one on the high and one on the low of the 8am candle of a 10 minute chart. I would like for it to be plotted historically as well.

2. How do I make it so that the lines that get plotted only extend to the right until a new bar makes a higher high or a lower low. example horizontal line on the high that I manually drew on the chart

I don't really even know where to start with this. I have some experience writing in Pinescript but not with drawing lines in the way I want. Any help would be greatly appreciated.

Answer 1

• Find out new session
• Save the high value in a var
• Start drawing until there is a new high
• Reset everything when it is a new session

Here is an example for the high:

//@version=5
indicator("My script", overlay=true, max_lines_count=500)
h = input.int(9, "Hour", minval=0, maxval=59)
m = input.int(30, "Hour", minval=0, maxval=59)

var float first_high = na
var bool can_draw = false
var line l = na

is_new_session = (hour == h) and (minute == m)
bgcolor(is_new_session ? color.new(color.green, 85) : na)

if (is_new_session)     // New session
    first_high := high  // Reset session high
    can_draw := true    // We are allowed to draw a line
    l := line.new(bar_index, first_high, bar_index, first_high, color=color.red)    // Get new line id
else
    if (can_draw)
        if (high > first_high)  // New high is made
            can_draw := false   // Stop drawing
        else
            line.set_x2(l, bar_index)   // Update x2 position of the line (move it to the right)