General Questions
Map-related Questions
Device-related Questions
Usage Questions
Currently only Linux. However, being based on Qt, it can theoretically also be compiled for Windows and Mac (or any other platform supported by Qt). QLandkarteGT is a similar open source project that actually supports all formentionned platforms.
Patches to enable QVCT support of new platforms are of course welcome!
Thanks to Olivier Bornet and Samuel Gaist for their contribution to Mac OS X support; Qt, GDAL and GPSD dependencies are readily available as part of the MacPorts project.
Excluding blank and comment lines, QVCT totals ∼25'000 lines of C/C++ code (25 KLOC).
I - Cédric Dufour (System and Software Engineer) - am the sole developer of QVCT. As a Linux evangelist, I had become fed up of switching to Windows to perform the navigation planning required by my private pilot activity. Additionaly, I wanted to have a touchscreen-friendly and ergonomic navigation software to use on my (Linux) tablet while under way.
Besides, using a PC to perform navigation tasks while in the same time holding the commands of an airplane or a ship raises several issues which I found weren't properly addressed in other existing (open source, Linux-compatible) software. Among those issues are: use your own (offline) maps (e.g. ICAO or marine charts), provide a clean and efficient user interface (suitable for a moving environment and a fast achievement of tasks), track multiple vessels, using multiple devices (GPS, compass, IAS/loch, pressure altimeter, etc.) for your own vessel (thus being able to distinguish between its true and apparent course), etc. QVCT answers those requirements (at least from my point of view).
No. You must create/use your own maps.
Theoretically, any image/file type supported by the Geospatial Data Abstraction Library (GDAL). In practice, you will most likely want to use GeoTIFF files, which are the most common geo-referenced files.
Yes, absolutely! Any image can be converted into a geo-referenced file - preferrably in GeoTIFF format - using the tools provided by the Geospatial Data Abstraction Library (GDAL).
Please refer to QVCT's User Manual for detailed instructions.
Yes, absolutely! Digital elevation models (DEM) can be converted to a geo-referenced file the same way as maps. They can then be associated to any map (and then even displayed) within QVCT.
No, not directly. One of the objective of QVCT is to be independent of any network connection. On the other hand, you can create offline versions of many
online map services using the Mobile Atlas Creator (MOBAC).
Please refer to QVCT's User Manual for detailed instructions.
On recent hardware, maps can be as big as 100-200MB, the Geospatial Data Abstraction Library (GDAL) being very good at working with large files (at least in GeoTIFF format).
I personally have maps of all Switzerland at 1:500000 (ICAO) and 1:200000 (topographic) which weight respectively 30MB and 120MB and
which I use daily on an Intel Core i5 2467M tablet.
In order to use an image file as a map, one needs to know how to translate pixel positions into (accurate) geographical positions.
In order to do so, the information about the reference and transformation systems that were use to create the map - the so-called datum (WGS-84, CH-1903, etc.), projection (Mercator, Lambert Conformal Conic, etc.) and ellipsoid (WGS-84, Bessel (1841), etc.) - must be available in the image file itself, using a format that allows such embedding (e.g. the GeoTIFF format).
The Geospatial Data Abstraction Library (GDAL) is a set of utilities that allow to achieve this georeferencing/embedding, relying on the PROJ.4 library to encode the georeferencing parameters and perform the transformations from one system to another.
To start with, any device that is supported by the GPS daemon (GPSD), used either as a GPS (single vessel localization) or AIS receiver (dynamic flotilla).
Also, any device that sends Kinetic Avionics's SBS-1 data over the wire may used used as ADS-B receiver (dynamic flotilla).
Yes, provided you have some knowledge of C/C++. The source code of QVCT includes a SAMPLE_DRIVER example that should allow you to create your own
device in a matter of minutes (if the device's protocol is simple enough). To give you a clue of the task at hand, each GPS daemon driver (GPS or AIS mode) is less than 400 lines of code.
Please refer to QVCT's Developer Documentation for further information.
Yes! There are several options available. I personally recommend you look into a Software Defined Radio (SDR) Receiver (such as for example the Nooelec R820T dongle) along Steve Markgraf's SDR-RTL Library and Salvatore Sanfilippo's Mode-S (ADS-B) Decoder.
The GPX format does not provide a way to gather landmarks (GPX waypoints) in distinct containers. Thus, when landmarks are saved in GPX format, they are all gathered in the same "pot".
No, not directly. On the other hand, one can use the gpsbabel utility to convert from/to the GPX format to/from most of the other existing file formats.
QVCT provides two way of managing vessels: either individually, by manually creating each vessel (and optionally associating one or more navigation devices to it for geo-localization purposes) or by associating a device to a flotilla, in which case it becomes dynamic, meaning that vessels will be automatically created (and geo-localized) as data appear on the device's wire.
The idea actually comes from the marine world, where several navigation devices are available (GPS, compass, loch, depth meter, etc.) and (potentially) linked together - usually using the NMEA 0183 protocol - to provide information in an integrated environment.
In QVCT, provided you do have several devices available, this allows in particular to distinguish the ground course from the apparent course (thus indicating the presence and importance of drift wind or current).