Spiderlines BTCUSD - daily/weekly

📘 Documentation – Daily and Weekly Spider Lines for Bitcoin
🔹 Purpose of the Script

This script draws dynamic “Spider Lines” in the Bitcoin chart.
The lines connect certain historical candles with a reference candle and extend to the right.
These act as guideline levels that can serve as potential support or resistance zones.

🔹 How It Works

The script operates in two modes, depending on the active chart timeframe:

Weekly Mode (timeframe.isweekly)

The reference date is July 1, 2019.

The number of weeks since that date is calculated.

This defines the connection candle (connection_candle).

Several predefined offsets (e.g., +32, +34, +36 …) are added to the reference to determine starting candles.

Lines are drawn from these candles toward the connection candle.

→ Line color: green

Daily Mode (timeframe.isdaily)

Same reference date: July 1, 2019.

The number of days since that date is calculated.

Again, a connection candle is set.

A different set of offsets (e.g., +224, +238, +252 …) defines the starting candles.

Lines are drawn accordingly.

→ Line color: red

🔹 Line Logic

Each line connects:
Start → bar_index[offset] at high[offset]
End → bar_index[connection_candle] at close[connection_candle]

Lines are extended indefinitely to the right (extend.right).

Appearance: dashed style, width 2.

🔹 Error Handling

If a calculated candle index does not exist in the chart history (e.g., chart data does not go back far enough),
a label is plotted in the chart showing the message:
"Daily idx out of range: 252"

This way, missing lines can be diagnosed easily.

🔹 Color Convention

Weekly Spider Lines → Green

Daily Spider Lines → Red

🔹 Use Cases

Visualization of historical cyclic line patterns.

Helps in technical chart analysis: spotting potential reaction zones in price movement.

Designed mainly for long-term traders and analysts observing Bitcoin in Daily or Weekly timeframes.

🔹 Limitations

Works only on Daily and Weekly charts.
Requires chart data going back to July 1, 2019.
Based purely on fixed offsets → not a classical indicator like Moving Averages or RSI.