State overlay system

This article is a stub. You can help the wiki by expanding it.

Status

To start FlightGear with an existing overlay add --state=statename to you command line.

For now there is no definitive list of possible states. These are my first suggestions:

• parking (meaning cold and dark)
• taxi (all systems running and ready to taxi)
• take-off (standing on the runway with take-off configuration)
• cruise (cruise configuration)
• approach (approach configuration)

Implementation

overlay file

To add state overlays to your aircraft, create a folder called states. In there you can put your $state-overlay.xml. In the beginning your overlay.xml should look like this:

<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<PropertyList>
  <name type="string" n="1">parking</name>
  <overlay>

  </overlay>
</PropertyList>

Now you can put your items, which need to be set between the overlay tags. Rule of thumb is that you use the hierarchy of the property-tree's root. It speeded up my research by quite a bit, when I found out, it's possible to dump the PropertyTree with a nasal command. Open up the Nasal-console from the developer-menu and put in the following: io.write_properties( path: "/home/myName/.fgfs/Export/PropTree.xml", prop: "/" );

Beware! This outputs the entire PropertyTree! This is several thousand lines long. You might want to dump only single folders of the PropertyTree by changing the "/" to sth like "/controls" or whatever folder you want to dump. Now you can simply delete everything from that file, that you don't need and copy&paste it into your overlay.xml.

include

Now you need to include your overlay.xml in your $Aircraft-set.xml file like this:

<PropertyList>
  <sim>
    ...
    <state include="states/parking-overlay.xml" n="0" />
    <state include="states/taxi-overlay.xml" n="1" />
    ...
  </sim>
</PropertyList>

Background

Wayne Bragg has been working a bit with James on the state overly system.

References

References