Using Visor · advanced · 8 min

The Bookmap — the Order Book Over Time

Every other order-flow surface in Visor answers a question about now or about aggregates: the DOM ladder shows the book this instant, the chart's footprint sums traded volume per candle. The Bookmap widget (bookmap) answers a different question: what has the book been doing? It draws the limit order book as a landscape over time — and because markets are a negotiation between resting orders and aggressive ones, watching that landscape evolve is watching the negotiation itself.

As with the whole tape track: this is reading the book as market information, never a suggestion to trade the asset. Everything on this panel is an observation.

The heat field

The background is the widget's core: time runs left to right, price runs bottom to top, and the brightness at each price is the resting size there — dark for nothing, blue for ordinary size, tipping into yellow and white only for outsized levels. The palette is normalised against the book's own recent distribution, so "bright" always means bright relative to this market right now.

Three things become visible that no snapshot view can show:

• Persistence. A bright band that runs flat for minutes is a resting order (or a stack of them) that stayed. Price often reacts around such bands — and sometimes doesn't. The band is the fact; the reaction is not promised.
• Pulling. A band that fades before price reaches it was cancelled, not traded. The spoofing lesson covers why that matters: a wall is an order, not a commitment.
• Consumption. A band that dims as price trades into it was eaten by aggressors. Same fade on screen, opposite story — the difference is whether the tape printed volume there. The widget's wall events (below) make that distinction for you, from the tape.

Bubbles: the aggressive side

Circles on top of the heat are executed trades, bucketed by moment and price: area scales with volume, and each bubble is split like a pie by aggressor side — teal for market buys, red for market sells. A large half-and-half bubble is a genuine two-sided battle; a large single-colour bubble is one side hitting into the book. The bubbles are the aggression; the heat is the patience. Reading the two together is the entire skill.

The stepped green/red lines running through the field are the best bid and offer — the negotiation's front line.

The sub-charts

Two toggles in the header mirror what the footprint and volume delta express on candles:

• CVD — cumulative volume delta across the visible window, off the true taker side of every print. The label says CVD · window because that is exactly what it is: the running buy-minus-sell within what you can see, not a session-anchored series.
• VP — traded volume at price for the recorded window, drawn against the right edge, with the highest-volume level (the POC) marked in gold.

Events: detections, honestly labelled

With Events on, the widget marks moments the order-flow monitor flagged, and lists the most recent in the corner:

• Sweeps — one side trading through several price levels in under two seconds.
• Absorption — heavy aggressive volume hitting a level that keeps standing. The passive side took everything thrown at it, and price didn't move through.
• Icebergs (inferred) — a level that keeps refilling after being hit, again and again. The word inferred is doing real work: Binance's public feed does not identify individual orders, so nobody reading it can prove an iceberg — the widget reports the refill pattern and says so. Treat it as evidence, not identification.
• Large lots — single prints far outside the recent size distribution (a self-tuning threshold, not a fixed number).
• Walls appearing and pulling — outsized resting levels near price, announced when they build, and marked pulled only when they vanish with almost nothing traded into them. Consumed walls don't get the label; the tape decides.

Every event is an inference from aggregated depth and the tape. None of them is a signal. A detected absorption tells you what happened at that level; it does not tell you what happens next.

If you want wall events without watching the panel, arm liquidity alerts for BTC or ETH in the Alerts panel — wall appearances and pulls will land in your feed, at most one every few minutes.

Replay and the sub-second view

The widget records everything it streams — book frames every quarter second, every trade, every event — for a rolling fifteen minutes. Drag the chart back (or touch a speed button) and a transport bar appears: play at 1×, 4× or 16×, scrub anywhere in the window, and hit ● Live to snap back. During replay the price gutter shows the book as of the playhead, not the live one.

Zoom in far enough and the columns resolve to their native quarter-second width, with the crosshair reading milliseconds. Two honesty notes: history from before the recent tail is stored at one-second resolution and renders that way (coarser bands — the widget never interpolates detail it doesn't have), and scrubbing to before the recording began shows darkness, because nothing was witnessed there.

Bookmap or OrderFlowMap?

Visor ships both on purpose. OrderFlowMap is a compact, opinionated heatmap panel — excellent as a glanceable tile. Bookmap is the deep-work surface: sub-second zoom, replay, detections, and the sub-charts. Add whichever fits the workspace — they read the same live feed and cap the same way per tier.