The visualizer toolbar configures the following options:

Sets the transparency: opaque nodes and transparent links (default), opaque network and transparent network.
 Sets the visualizer background to black (moon) or to white (sun). Also changes the way the transparency is treated (additive VS subtractive).
Renders or hides self-loops (self links) in the network.
 Toggles node or link selection.
Switches ON/OFF the lighting mode, which hides links during network movement. Use it for big networks to speed visual performance.
Highlight adjacent nodes mode relative to the current selection: highlights all (default), commons, or none of the neighbors.
Show/hides links.
Shadows inactive elements (not selected nor highlighted).
Switches on/off network rotation.
Shows or hides node/link tags.
Isolates selection, hides selection, or restores the default full visibility.
Visualizer Help, with mouse controls and keyboard shortcuts.

The visualizer provides a tool to save, expand and recover selections defined by the user. It is located on the lower part of the screen:

 
 

Clicking on the numbers lets you either save a selection when the button is empty or recover a previously saved selection. You can also do it with the keyboard, pressing ‘SHIFT + [0..9]’ to save a selection and pressing a number to recover.

The two charts on the lower-left corner indicate the number of selected nodes/links (green) and adjacent (purple). Move the mouse over the chart to see the percentages of selected/adjacents.
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