• derived nodes inherit all messages from their base classes
  
• see reset method for default settings
  
• the default logic will turn the switch on when the viewer is inside any of the given spaces.
  
• the switch logic can be overriden with the mode message
  

constructor visibility

destructor ~visibility

method reset

1 clear the local space array
2 if net master then clear net space array

method message

1 make visible when inside space
2 make visible when outside space
3 add a space node
4 set mode to normal, on or off

method addSpace

1 find space node
2 if node is found then add to space array

method app

1 if mode is off then switch off
2 else, if mode is on switch on
3 else determine if any space contains user

3.1 for all spaces in array

3.1.1 if space contains user then set inside flag true

3.2 if inside flag is true then switch on, else switch off