This ProBuilder script is designed to identify and draw support and resistance levels based on price pivots over a specified number of bars. It helps in visualizing key price levels which could act as barriers to price movements.

DEFPARAM CalculateOnLastBars = 1000
//DEFPARAM DrawOnLastBarOnly = true
PivotBAR = 2 //2 bars AFTER pivot
LookBack = 4 //3 bars BEFORE pivot
BarLookBack = PivotBAR + 1

IF low[PivotBAR] < lowest[LookBack](low)[BarLookBack] THEN
    IF low[PivotBAR] = lowest[BarLookBack](low) THEN
        MySupport = BarIndex - PivotBAR
        SupportPrice = low[PivotBAR]
    ENDIF
ENDIF

IF high[PivotBAR] > highest[LookBack](high)[BarLookBack] THEN
    IF high[PivotBAR] = highest[BarLookBack](high) THEN
        MyResistance = BarIndex - PivotBAR
        ResistancePrice = high[PivotBAR]//high[BarIndex - MyResistance]
    ENDIF
ENDIF

DRAWSEGMENT(MyResistance,ResistancePrice,BarIndex,ResistancePrice) COLOURED(255,0,0,255)
DRAWSEGMENT(MySupport,SupportPrice,BarIndex,SupportPrice) COLOURED(0,128,0,255)

RETURN

Explanation of the Code:

• DEFPARAM CalculateOnLastBars = 1000: This line sets the number of bars to calculate the script on to the last 1000 bars.
• PivotBAR and LookBack: These variables define the number of bars after and before the pivot point to consider for identifying support and resistance levels.
• Conditional Statements: The script uses nested IF statements to determine if the current low and high are the lowest and highest points within the defined lookback period, respectively.
• MySupport and MyResistance: These variables store the bar index adjusted by the pivot bar index, identifying the exact location of support and resistance.
• DRAWSEGMENT: This function is used to draw lines on the chart at the identified support and resistance levels. The lines are colored red for resistance and green for support.

This script is useful for traders who need to visually identify and analyze key price levels that could influence future price movements.