This indicator is a Z-score–normalized order flow tool, built around Cumulative Volume Delta (CVD) and per-bar delta, designed to measure how aggressive buying or selling is relative to recent history.

🧠 Core concept

At its heart, this script tracks order flow imbalance:

• Buys (orderflow.buy) → aggressive market buying
  
• Sells (orderflow.sell) → aggressive market selling
  
• Delta = Buys − Sells → net aggression per candle
  

It then standardizes this using a Z-score, so instead of raw numbers, you see:

👉 “How extreme is current buying/selling compared to normal?”

📊 Two operating modes

1. useDeltaZ = true (default)

• 
  Uses per-bar delta
• 
  Focuses on short-term aggression spikes

👉 Best for:

• 
  Scalping
  
• 
  Spotting sudden buying/selling bursts
  

2. useDeltaZ = false

• 
  Uses CVD (cumulative delta)
• 
  Focuses on position buildup over time

👉 Best for:

• 
  Trend confirmation
  
• 
  Detecting sustained accumulation/distribution
  

📈 Z-score interpretation

🟢 Above 0 (green fill)

• 
  Buying pressure dominates
  
• 
  Positive delta relative to average
  
• 
  Indicates buyers are more aggressive than usual

👉 Context matters:

• 
  Rising price + positive Z → strong bullish participation
  
• 
  Falling price + positive Z → possible absorption (hidden selling)
  

🔴 Below 0 (red fill)

• 
  Selling pressure dominates
  
• 
  Negative delta relative to average
  
• 
  Indicates sellers are more aggressive than usual

👉 Context:

• 
  Falling price + negative Z → strong bearish conviction
  
• 
  Rising price + negative Z → possible hidden accumulation
  

⚡ Extreme values (|Z| > 2 or 3)

• 
  Statistically rare events
  
• 
  Signal unusual order flow imbalance

These zones often precede:

• 
  Liquidity grabs
  
• 
  Exhaustion moves
  
• 
  Sharp reversals or continuation bursts
  

🎛️ Smoothing logic

The indicator applies optional smoothing:

• SMA smoothing → stable, less noisy
  
• EMA smoothing → faster, more reactive
  

👉 Effect:

• 
  Reduces noise from raw delta spikes
  
• 
  Makes trends in order flow easier to read
  

🎨 Visual structure

• Blue line (zLine) → normalized order flow strength
  
• Zero line (red) → neutral boundary
  
• Fill:
  
• 
  Green → bullish dominance
  
• 
  Red → bearish dominance
  

This creates a momentum-style oscillator, but based on real trading activity, not price alone.