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The remaining keystrokes are: 

• M - Toggle offline device visibility
  • Normally, offline devices are shown as grayed-out icons. This can be toggled to where offline devices are hidden instead.
• B - Toggle background image
  • The map of the Continental US can be toggled off and on.
• S - Toggle sprite layer
  • The sprite layer (with injected sprites) can be toggled on and off.
• X - Lock / unlock node positions
  • The default is to allow click-and-drag to move nodes (devices & hosts) on the display. 
• Z - Toggle oblique view (Experimental)
  • This mode will show a "sideways" view of the network, separating packet-layer nodes from optical-layer nodes.
  • As noted, this mode is currently experimental.
    
    

Topology Overlay Components

An ONOS application can provide a Topology Overlay Component to inject additional detail and behavior to the topology view.

Background Map

The background map provides a geographic reference for the topology. The default map is the Continental US. The map layer's visibility can be toggled on and off with the 'B' (for background) key.

See Providing Alternate Maps for the Topology View for additional details.

Custom Sprites

The Topology Sprite Layer mechanism allows custom "background" elements to be displayed (above the background map, but below the topology elements). This could be used, for example, to inject labeled "subnet clouds", or the plan of an office building or campus into the topology view. Typically, one would want to hide the background map layer (press 'B') and show the sprite layer (press 'S') instead.

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