在不同格式之间转换空域文件的 工具：OpenAir、openAIP、KML/KMZ、Polish 和 Garmin _C++

AirspaceConverter ================= A multi-platform and open source tool to convert between different airspace and waypoint formats. Can read airspace and waypoint files in the following formats: - _OpenAir_ - _openAIP_ - KML/KMZ - _SeeYou_ - _LittleNavMap_ Can write in the following formats: - KMZ - _OpenAir_ - _SeeYou_ - _LittleNavMap_ - _Polish_ - _Garmin_ IMG While converting to _OpenAir_ AirspaceConverter estimates if the points are part of arcs or circumferences in order to make use of arc and circumference definitions of the _OpenAir_ format and so avoiding to output all points one by one. The ability to read **KML**/**KMZ** is based on the **KMZ** airspace files produced by _Austrocontrol_. This utility can convert also _SeeYou_ **.CUP** waypoint files to **KMZ** (for _Google Earth_). The conversion to **IMG** for _Garmin_ devices is done using _cGPSmapper_. AirspaceConverter is written in C++11 and runs on _Linux_, _Windows_ and _macOS_. In order to be immediately easy to use it has _Qt_ and _Windows MFC_ user interfaces. But it can also work from command line. For more information's about this project: [alus.it/AirspaceConverter](https://www.alus.it/AirspaceConverter) Contributors are, always, warmly welcome! Why this software? ------------------ Airspace represented in 3D in _Google Earth_ can help to visualize and better understand the airspace structure. Not only, having the planned route or track of a flight (as GPX file), displayed as well in _Google Earth_ will make easy to check for airspace crossed or to be avoided. This software can also be useful for maintainers of _OpenAir_ airspace and _SeeYou_ waypoints files, not only to visualize airspace and waypoints but also to verify the syntax of _OpenAir_ or _SeeYou_ lines entered. Duplicate consecutive points will be ignored, the converter will warn about them while reading _OpenAir_ files. This will also detect the special case of an unnecessary point repeating the end of the arc defined on the previous line. For the "landable" waypoints in the **CUP** files an estimation of the runway perimeter is drawn on the earth surface, in order to do that not only the position is used but also the runway orientation and length. This is particularly useful to verify that the position of the airfield in the **CUP** file matches exactly the runway in _Google Earth_. In software like _LK8000_ the airfield position is considered as the exact center of the runway, orientation and length are used to assist for landing with an HSI and glide slope indications thus the correctness of position, orientation and length becomes really important. _openAIP_ (http://www.openaip.net/) provides a free, worldwide and updated airspace and waypoint repository but in his own format, while many devices and software support _OpenAir_ airspace files. This software can convert: _openAIP_ airspace to _OpenAir_ and _openAIP_ waypoints to _SeeYou_; so making _openAIP_ data available to many portable devices. AirspaceConverter can be used also to merge together several airspace or waypoint files (_openAIP_ repeated airspaces will be automatically removed) and filter the result on a specific range of latitudes and longitudes. Converting _openAIP_ files to _OpenAir_ has also the advantage to reduce significantly the size of the total airspace database used on a portable device. For example _LK8000_ recently supports also the _openAIP_ format (feature that I implemented) but it is not always possible to load bigger _openAIP_ files on older PNA devices, while the same files converted in _OpenAir_ yes. There are also cases where the "official" airspace files are available only in KML format like the Austrian airspace from _Austrocontrol_, also in this case is possible to convert it to _OpenAir_. In case is required to import long lists of points (like state borders) from KML LineString tracks: just use the option `-t` and the tracks found will be closed and treated as unknown airspace. Then it will be possible to adapt the airspace definitions manually in the so converted _OpenAir_ file. About KML format ---------------- The _[Keyhole Markup Language](https://developers.google.com/kml/)_, used by _Google Earth_ is probably a good format to define models of buildings but it is not exactly practical to define airspace. This because it not possible, at least from my understanding, to define in the same 3D object points at altitudes with different references: it is the typical case of an airspace with AGL floor and AMSL ceiling. One possible solution is to translate, where necessary all the altitudes to the same reference but to do that we need the know the altitude of the terrain at every location, reason why this software uses terrain maps. Another important limitation of KML is that surfaces which follow the terrain are possible only at terrain altitude. So please, be advised that, what you will see in _Google Earth_ will not exactly match how airspace definitions are really intended. LK8000 terrain raster map files ------------------------------- This program uses the same terrain raster maps (**.dem**) of _LK8000_ to convert altitudes from AGL to AMSL. Also while importing _SeeYou_ waypoints with null altitude (except unknown and normal types) the ground elevation will be used as altitude of that point. For doing this the terrain raster maps must be loaded before the waypoints. Ground heights between -5 and 5 meters will be anyway considered AMSL. In case the loaded terrain maps are overlapping, the one with the best resolution will be automatically used. On the _LK8000_ website there is a [wide terrain raster map collection](https://www.lk8000.it/download/maps.html). The part of this program reading and using the terrain maps has been derived and adapted from _LK8000_ project. To know more about _LK8000_ project: [lk8000.it](https://www.lk8000.it/) The repository of _LK8000_ is available here: [github.com/LK8000](https://github.com/LK8000/LK8000) AirspaceConverter shared library -------------------------------- This software is designed to keep completely separated functionalities from the user interfaces. All the reading, writing and conversion features are in a common shared library: libAirspaceConverter can be compiled under different platforms and so used from different user interfaces. AirspaceConverter command line ------------------------------ The `airspaceconverter` command line executable, works taking several arguments, for example: `airspaceconverter -q 1013 -a 35 -i inputFileOpenAir.txt -i openAIP_asp.aip -w waypoints.cup -w openAIP_wpt.aip -m terrainMap.dem -o outputFile.kmz` Possible options: - **-q**: optional, specify the QNH in hPa used to calculate height of flight levels - **-a**: optional, specify a default terrain altitude in meters to calculate AGL heights of points not covered by loaded terrain map(s) - **-i**: multiple, input file(s) can be _OpenAir_ (**.txt**), _openAIP_ (**.aip**), _Google Earth_ **.kmz**, **.kml**) - **-w**: multiple, input waypoint file(s) can be _SeeYou_ (**.cup**), _openAIP_ (**.aip**) or _LittleNavMap_ (**.csv**) - **-m**: optional, multiple, terrain map file(s) (**.dem**) used to lookup terrain heights - **-l**: optional, set filter limits in latitude and longitude for the output, followed by the 4 limit values: northLat,southLat,westLon,eastLon where the limits are comma separated, expressed in degrees, without spaces, negative for west longitudes and south latitudes - **-o**: optional, output file **.kmz** (_Google Earth_), **.txt** (_OpenAir_), **.cup** (_SeeYou_), **.csv** (_LittleNavMap_), **.img** (_Garmin_) or **.mp** (_Polish_). If not specified will be used the name of first input file as **KMZ** - **-p**: optional, when writing in _OpenAir_ avoid to use arcs and circles but only points (DP) - **-s**: optional, when wr