The wrap flow panel uses an NWrapFlowLayout (see Wrap Flow Layout) to arrange it's child widgets. It places widgets on a new lane, when the current lane breaches the size constraint of the layout area in the current layout flow direction (i.e. wraps the cells in the layout flow direction).

The image below shows a sample stack panel with 16 buttons:

The image was produced by the following code:

NWrapFlowPanel wrapPanel = new NWrapFlowPanel();
wrapPanel.HorizontalSpacing = 3;
wrapPanel.VerticalSpacing = 3;
        
for (int i = 1; i <= 16; i++)
{
    wrapPanel.Add(new NButton("Button " + i.ToString()));
}