Building the chart

Volume bars

The histogram under the price plot: where its numbers come from when you didn't import any, and when the bars arrive.

Quick steps

Where the numbers come from
Unless you imported a CSV with a volume column, there is no real volume behind your chart — so each bar is worked out from its own candle: the bigger the move, the taller the bar. It is stable, not random, so the same chart always draws the same bars.
Set a bar yourself
Drag a bar's top edge to the height you want. That pins the value, and the bar stops following its candle. Reset it in the panel to hand it back.
Point at one bar
Click a bar to select its candle, then give it an accent colour — that is how you show the one spike a lesson is about without drawing anything on top of it.
The pane takes space
Switching bars on shortens the price chart to make room, in the editor and in the export alike. Drag the line between the chart and the bars to decide how much — you can watch how much video you are giving up as you drag.
When the bars arrive
By default each bar rides in with its own candle. "All at once" instead brings the whole profile up at a single moment — leave the start column empty for the very end of the video, or set one to make the point mid-chart. With their candles, a start column means the bars simply begin there.

The volume pane is a histogram under the price plot. Press b and tick Show volume bars.

It is a layout split, not an overlay

Turning the pane on shortens the price chart to make room, in the editor and in the export alike. That is why it has no eye in the Visible list: an eye that reflows half the composition is not an eye, it is a layout change pretending to be one.

The divider between chart and bars is the height control. Drag it and the price plot shrinks under your pointer, so you can see exactly how much picture you are giving up. It clamps near the bottom rather than switching the pane off — losing a whole layer to an overshot drag is a nasty surprise, and the checkbox is right there.

Unticking Divider line removes it from the composition. The hover highlight still draws in the editor, because that line is also the resize handle and a handle nobody can find is worse than a divider nobody wanted. The exported frame carries no line.

Where the numbers come from

Most charts here are hand-drawn or generated, so there is no real volume behind them. A candle with no volume of its own gets a derived bar: roughly its range plus its body size, with a small jitter seeded from the candle's own id.

Two consequences worth knowing:

It is stable, not random — the same chart always draws the same bars.
It is correlated with the move, on purpose. "The breakout came with volume" is the lesson people are trying to show, and random bars cannot show it.

Deriving never writes the value. Regenerate a Market Block and its bars match the new candles instead of being frozen at the old ones.

Imported and derived bars share one scale

If some candles carry real volume and others do not, the two are matched by their medians rather than their maxima — a single imported spike would otherwise drag every derived bar down to nothing.

Setting a bar by hand

Drag a bar's top edge, or type into Value in the panel. That pins the number and the bar stops following its candle; resetting the field hands it back.

The scale is fixed over all candles, exactly as the price range is. A scale that grew with the reveal would shrink earlier bars retroactively, and two bars separated in time could no longer be compared. Scale top pins it to a number of your own.

Pointing at one bar

Click a bar to select its candle, then give it an accent colour. That is how you show the one spike a lesson is about without drawing anything on top of it.

The panel deliberately stays on the Volume tool when you do this — otherwise picking your bar would hand the panel to the candle tool and take the volume controls away.

When the bars arrive

Bars reuse the candles' own reveal clock, so by default each rides in with its candle.

Bars appear offers two modes:

With their candles, plus an optional start column. Candles before that column get nothing at all, even at the end of the video — "volume from candle 30" means the pane stays empty to its left, full stop.
All at once, which brings the whole profile up at one moment. A start column makes that point mid-chart; leaving it empty puts it at the very end.

In All at once, no bar ever outruns its own candle. A histogram drawing the future would give the answer away.

Note

The pane itself is reserved from frame zero either way. A pane that appeared mid-video would move the price plot, and with it the camera framing and the overlay anchoring — so the pane is fixed and only the bars are timed.

There is no disappears-at and no transition control, so the panel shows one timing field rather than the usual three. There is also no number printed beside a bar: labelling a derived value would claim market data that does not exist.