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AI Traffic: Difference between revisions
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→Ground networks: A technical perspective
(Updated part of the documentation to reflect FlightGear 1.9.0) |
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'''Documentation updated until here.''' | '''Documentation updated until here.''' | ||
= Ground networks = | |||
The first section of the file contains the parameters of the airport's parking | The next major aspect of the AI traffic system contains taxiway information. Although the physical layout of each airport is contained in FlightGear's airport database, this information is not sufficient to provide taxiway information. Therefore AI aircraft pickup this type of routing information from an xml file inside the data/AI/Airports directory/. Currently, this information is provided on a one file per airport basis, that can be found in a file called data/AI/Airports/[ICAO]/parking.xml, where ICAO stands for the 4 letter ICAO code for the airport in question. | ||
locations. | |||
network, and the final section contains a list of segments or "arcs" as David | For example, see the ground network for EHAM, which is found in <tt>data/Airports/AI/EHAM/parking.xml</tt>. See the end of this page for a small | ||
excerpt from this file. It should be noted that current development work is planned that aims to move these files from the base package to the scenery repository, so that ground network information and the physical layout of the airport can be updated in parallel. Once this is done, the new location / name for the file will be [fg-scenery]/Airports/[ICAO1]/[ICAO2]/[ICA03]/[ICAO].groundnetwork.xml. Here [ICAO] stands for the 4 letter ICAO code of the airport in question, and [ICAO1], [ICAO2], and [ICAO3] for the first to third letter of this code. This move is expected to be finished in the Winter/Spring of 2009. | |||
== A technical perspective == | |||
A ground network file consists of 4 major sections. The first section is optional, although recent version of TaxiDraw add this section automatically. This section contains a list of all the radio frequencies for the airport in question. FlightGear currently (as of 1.9.0) uses these frequencies to display some ATC messages. As of FlightGear 1.9.0, only startup approval requests are implemented. You can "hear" these by tuning to the first ground frequency listed in the frequencies section. | |||
The second section of the file contains the parameters of the airport's parking | |||
locations. The third section contains a list of all the nodes in the ground | |||
network, and the fourth and final section contains a list of segments, or "arcs" as David | |||
Luff called them initially, which basically describe which node is connected | Luff called them initially, which basically describe which node is connected | ||
to which other node. | to which other node. | ||
Each parking and | Each parking and AI node has a unique index number, which is used by the | ||
segments to link the startup location and the taxiways together. Parkings and | segments to link the startup location and the taxiways together. Parkings and | ||
AI nodes have the following parameters: | AI nodes have the following parameters: | ||
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* lon (position in longitude) | * lon (position in longitude) | ||
* name (name as found on airport charts: e.g. D23, or C1). | * name (name as found on airport charts: e.g. D23, or C1). | ||
* number | |||
The name parameter is currently used by flightgear only for the Parking names. will be used in future ATC, but AINode names will probably not be used except for some specific internal functions. | |||
airlineCodes= list any (comma separated) ICAO airline codes here to specify | airlineCodes= list any (comma separated) ICAO airline codes here to specify | ||
which airlines are allowed here. | which airlines are allowed here. | ||
* pushBack (used to determine whether departing aircraft can make left or right | |||
turns after pushback | turns after pushback | ||