Return to base directive

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A Return to base directive (RTB directive for short) is a jargon expression the FreeSpace community uses to refer to a directive that tells the player when he is allowed to return to base. All non-red-alert missions that have debriefing must have one (and no more) RTB directive. Missions that are chained using red-alert don't typically have an RTB directive, because the mission ends automatically as soon as certain mission objectives are met.

Creating an RTB directive

The FREDder will need at least two Events for a properly working RTB directive. (More than two, if the RTB is at the end of a chain of Events.) The first directive collects all the necessary conditions that should be met to trigger the RTB directive. The second is the "Return to base" directive itself. It must be chained to the first Event, otherwise the "Return to base" directive will pop up immediately. Typically, the RTB directive consists of a has-departed-delay SEXP that checks if the player has jumped out.

Chaining one Event to another is possible by ticking the "Chained" feature. A chained event is connected to the event that precedes it only. So, in simpler terms, the RTB directive's Event must be directly below the "collect all outcomes" one. Add the "Return to base" Directive Text to your Event.

Throught an example

In this example mission, the player's wing is ordered to destroy an Aeolus cruiser that jumps out after 45 seconds. Two possibilities should be accounted for by the RTB directive:

  • The cruiser gets destroyed
  • The cruiser escapes

Either will trigger the RTB directive. Logically, the two cannot happen at the same time, so the FREDder is restricted to using the or SEXP instead of and. The RTB chain should look like this:

RTBSampleExpanded.JPG

Interpretation of the example

The "Gorre directive" is to be ignored. It only gives the "Destroy the Gorre" directive in the Directives window. It is unrelated to the RTB chain.

The "Conditions to depart" Event collects all the necessary conditions that trigger the "Return to base" directive. The sample mission could have used the much more straightforward destroyed-or-departed-delay, but the way it is done here is more demonstrative, because here is the aforementioned or conditional. If the Gorre (the Aeolus) is destroyed or escapes, the Event will turn true and trigger the RTB directive. For an RTB directive, it makes no difference if the mission's outcome is favorable or unfavorable to the player. (This Event can also be used for making AWOL debriefing stages. The send-message SEXP will send a message that tells the player that he is allowed to jump out (optional).

The "RTB directive" Event will give the "Return to base" directive. Apparently, it is chained to the "Conditions to depart" Event. FreeSpace ignores a chained Event until the Event that it is chained to becomes true. If the "Conditions to depart" Event is true, the "RTB directive" Event will be triggered. Once triggered, it will work like any other Events, so its "Return to base" directive will be displayed on the HUD.

Miscellaneous notes

  • You can name the Events however you prefer. The point is that you should be able to recognize the Events based on their names. If you're working with dozens of ambiguously named Events, you will not be able to tell which one does what without opening the tree.
  • The "Chained" option should never be ticked for the first Event of a given chain. Otherwise, FreeSpace will assume that the event that is above it is the first element of the chain.

External links

Sample mission (Tested in FreeSpace Open 3.6.9., optimized for Easy, could be used to learn about AWOL debriefing stages.)