> For the complete documentation index, see [llms.txt](https://help.za.velocitytrade.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://help.za.velocitytrade.com/desktop-application-for-windows/windows/analysis-tools/chart/level-ll-data-on-chart.md).

# Level ll data on chart

This functionality allows to actualize the possibility to represent the structure of changing of Level II on 1 Tick Chart.

![](/files/-MgF4BKFog48wRCemDGK)

The functionality becomes available after activation of checkbox 'Order Flow surface'.

![](/files/-MgF4BKK_kkAsKfegwdL)

The checkbox synchronizes with the same checkbox in the chart settings.

The functionality is available only for aggregation 1 Tick.

In checkbox 'Order Flow surface', the default state is false, the checkbox is available only if 'Value' = 1, otherwise the checkbox is disabled.

Other place for activating functionality is the menu Setting -> Data style (only for 1 tick aggregation).

![](/files/-MgF4BKL-qVhL3Ws7h9b)

If 'Order Flow surface' is active, the rest of settings becomes available.

* Aggregation mode – combobox allows to indicate a method that determines how the maximum value of volume is calculated:

Auto - in this mode, the system independently calculates the maximum volume from the incoming level 2 data. This value is used while drawing a histogram. Auto mode is set by default.

Custom - in this mode, the user indicates the maximum value by himself.

* Value – numeric for custom maximal value. Numerics becomes available only when Aggregation mode = custom.
* Number of levels – numeric, by default = 5, min = 1, max = without limit, Step = 1. This numeric allows to indicate how many levels of Level II have to be shown on a chart.
* Font, Font color – allows to choose font style.
* Show volume markers – the default state of the checkbox is false, when this checkbox is activated, controls 'Font', 'Color', 'Area' are activated. This setting enables to display the volume markers on the Y axis. These markers show the current volume value at each level of Market depth. 

![](/files/-MgF4BKMvrUK2XXrpeMq)

The field is depicted in proportion to the maximum value.

Sell limit orders are depicted from the initial level down.

Buy limit orders are depicted from the initial level up.

**Histogram building**

Histogram building occurs in real time from the moment when the checkbox 'Order Flow surface' is activated. The redrawing of the histogram occurs after the emergence of a new quote, i.e. at the moment of its drawing. Building of a histogram does not depend on the Data type of a chart. Zooming of a chart does not change the functionality. The histogram which is built should have a lower Z-Index than the chart itself.

In the settings there is a combobox 'Coloring scheme' with two states - 'Histogram' and 'Gradient'.

![](/files/-MgF4BKNY5szmamoY2zw)

The example of Gradient coloring scheme is shown on the first screenshot.​

![](/files/-MgF4BKOEZxk6X370eIC)

* Limit orders - сolorpickers, default values for Buy limit - blue, for Sell limit - red.
* New limit order - the coloring occurs when the volume changes one time at this level, for example, if at the level of 2000 there is a volume of 200 lots and if at some time at this level the volume changes to 202 - at this moment coloring New limit order should occur. Default values for New buy limit - another shade of blue, New sell limit - another shade of red.

The example of Histogram coloring scheme is shown below:​

![](/files/-MgF4BKPT5G_FVwkNTwR)